JP6033586B2 - Lighting device and vehicle headlamp - Google Patents

Description

  The present invention relates to a lighting device and a vehicle headlamp capable of realizing a specific light distribution pattern.

  Patent Documents 1 to 4 disclose examples of an illumination device that uses fluorescence generated by irradiating a phosphor with excitation light emitted from an excitation light source as illumination light.

  In the light source device described in Patent Document 1, excitation light emitted from a plurality of excitation light sources is guided by optical fibers, and a plurality of phosphors are excited by the guided excitation light, thereby switching colors. Is going.

  Further, in the light emitting device described in Patent Document 2, the excitation light guided by a plurality of optical fibers is irradiated to different portions of the light emitting unit, so that the excitation light is intensively irradiated to one place. This reduces the possibility that the light emitting portion will be significantly deteriorated. Further, in Patent Document 2, by increasing the density of the emission end portion of the optical fiber in the central portion of the light emitting portion, the central portion is made to emit light more strongly than the other portions, and the central portion of the region irradiated by the headlamp is A configuration for increasing the illuminance is disclosed.

  Moreover, the vehicle headlamp described in Patent Document 3 is an example of a lighting device that realizes a predetermined light distribution pattern. This vehicle headlamp includes a plurality of light source units that generate white light by irradiating a phosphor with laser light (ultraviolet light), and by adjusting the direction of the optical axis of each light source unit, Realizes light distribution pattern.

  Further, the illumination device described in Patent Document 4 discloses a configuration in which illumination light is obtained by irradiating a phosphor unit with excitation light emitted from a semiconductor laser and guided by an optical fiber.

JP 2010-17305 A (published January 28, 2010) JP 2011-243370 A (released on December 1, 2011) JP 2005-150041 A (released on June 9, 2005) JP 2009-43668 A (published February 26, 2009)

  However, the vehicle headlamp described in Patent Document 3 has a problem that a plurality of light source units are provided in order to realize a desired light distribution pattern, and the vehicle headlamp is increased in size. Note that Patent Documents 1, 2, and 4 do not disclose a configuration that should be noted as a configuration for realizing a desired light distribution pattern.

  The present invention has been made to solve the above problems, and an object of the present invention is to provide a small illuminating device capable of realizing a desired light distribution pattern.

In order to solve the above-described problem, an illumination device according to the present invention
A light bundle composed of a plurality of incident light incident from the incident section, and guides the light bundle having a specific light intensity distribution while maintaining the light intensity distribution, and a light guide section that emits from the output section;
A light source unit including a light source and a mirror that generates the incident light incident on the incident unit by reflecting the light emitted from the light source;
A light projecting unit that projects the emitted light emitted from the emitting unit or the light converted from the emitted light to the outside;
A light intensity distribution controller that changes the light intensity distribution of the light flux by changing the light intensity and optical path of each incident light by controlling the output or the angle of the mirror while controlling the output of the light source. When,
It is characterized by having.
In addition, the mirror is a MEMS mirror including a micro mirror formed by fusing a mechanical part and an electronic circuit to form a fine part.
Preferably, the light intensity distribution control unit changes the light intensity distribution of the light flux by changing the light intensity and the optical path of each incident light by controlling the position or angle of the micromirror.
In addition, the light source unit includes a plurality of the mirrors,
The light intensity distribution control unit preferably changes the light intensity distribution of the light flux by changing the light intensity and optical path of the incident light by controlling the position or angle of each mirror.

  With the above configuration, the incident light generated by the light source unit and incident light having a specific light intensity distribution is incident on the incident unit, and is guided by the light guide unit while maintaining the light intensity distribution. The emitted light emitted from the emitting part is projected to the outside by the light projecting part. Alternatively, the emitted light is converted and projected to the outside by a light projecting unit. Thereby, the light distribution pattern of the illumination light projected from the light projecting unit corresponds to the light intensity distribution of the incident light generated by the light source unit.

  Therefore, a small illuminating device that can realize a desired light distribution pattern can be realized.

  Moreover, it is preferable to further include a light intensity distribution generation unit that generates a light intensity distribution of the incident light.

  According to said structure, the light intensity distribution of the incident light produced | generated by a light source part can be produced | generated, and the light projection pattern according to this can be obtained.

  The light intensity distribution generation unit includes, for example, a configuration that generates a predetermined light intensity distribution by arranging a plurality of laser elements and the like, and further, a predetermined light intensity distribution using a control device or the like. A configuration for generating

  It is preferable to further include a light intensity distribution control unit that changes the light intensity distribution of the incident light.

  According to said structure, a light projection pattern can be changed by changing the light intensity distribution of the incident light produced | generated by a light source part. Therefore, the light projection pattern can be changed by a smaller mechanism than the conventional light projection pattern changing mechanism in which the optical axes of the plurality of light source units are changed. The light intensity distribution control unit may be the same member as the light intensity distribution generation unit.

The light source unit includes a light emitting unit that emits fluorescence in response to excitation light,
The light source emits the excitation light,
The mirror irradiates the light emitting part by reflecting the excitation light, generates the fluorescence as the incident light incident on the incident part,
Preferably, the light intensity distribution control unit changes the light intensity distribution of the light beam by changing an irradiation pattern of the excitation light in the light emitting unit.

  According to said structure, a light projection pattern can be changed by changing the irradiation pattern of the excitation light in a light emission part. Therefore, the light projection pattern can be changed by a smaller mechanism than the conventional light projection pattern changing mechanism in which the optical axes of the plurality of light source units are changed. In particular, since the mechanism for changing the projection pattern is provided in the light source unit, the projection unit can be reduced in size.

The light source unit is
A light emitting section that emits fluorescence in response to excitation light;
It is preferable to include a condensing unit that condenses the fluorescence emitted from the light emitting unit as the incident light on the incident unit.

  According to said structure, fluorescence can be efficiently entered into a light guide part by condensing the fluorescence which the light emission part emitted on the incident part by the condensing part. For example, the light emitted from the light emitting part can be condensed on the incident part by arranging the light emitting part and the incident part at positions where they are optically conjugate with each other by the light collecting part.

  Moreover, it is preferable that the said light collection part is an elliptical mirror.

  According to said structure, fluorescence can be efficiently incident on a light guide part by using an elliptical mirror as a condensing part. For example, by arranging the light emitting unit in the vicinity of one of the two focal points (first focus) of the elliptical mirror, the light emitted from the light emitting unit is reflected by the reflection curved surface of the elliptical mirror. The light can be condensed on the other focal point (second focal point) of the elliptical mirror.

In addition, a light emitting unit that emits fluorescence in response to excitation light is further provided,
The light guide part emits the excitation light from the emission part as the emitted light,
The light projecting unit preferably projects the fluorescence emitted from the light emitting unit.
According to the above configuration, the light source unit generates excitation light having a light intensity distribution corresponding to a desired projection pattern, and the light guide unit guides the generated excitation light while maintaining the light intensity distribution. Shine. The light emitting unit converts excitation light into fluorescence, and the light projecting unit projects the fluorescence to the outside. Therefore, the illumination light projected from the light projecting unit forms a desired light projecting pattern.

  Therefore, a small illuminating device can be realized as compared with the conventional configuration in which a plurality of light source units are provided to realize a specific light distribution pattern.

  Moreover, it is preferable that the said light guide part is a multi-core fiber.

  By using a multi-core fiber as the light guide unit, light incident on the incident unit can be guided to the output unit without substantially damaging the light intensity distribution.

  Moreover, it is preferable that the said light guide part is a bundle fiber.

  By using a bundle fiber as the light guide unit, the light incident on the incident unit can be guided to the output unit without substantially damaging the light intensity distribution.

  Moreover, the vehicle headlamp provided with the said illuminating device is also contained in the technical scope of this invention.

The lighting device according to the present invention is as described above.
A light guide unit that guides incident light having a specific light intensity distribution incident from the incident unit while maintaining the light intensity distribution;
A light source unit that generates the incident light incident on the incident unit;
And a light projecting unit that projects the emitted light emitted from the emitting unit or the light converted from the emitted light to the outside.

  Therefore, there is an effect that a small illuminating device that can realize a desired light distribution pattern can be realized. In particular, there is an effect that a small light projecting unit can be realized.

It is a figure which shows the structure of the headlamp which concerns on one Embodiment of this invention. It is a figure which shows an example of the incident end surface of the multi-core fiber with which the said headlamp is equipped, (a) is sectional drawing which shows the case where the core of the same shape is arrange | positioned concentrically, (b) is a horizontally long core. It is sectional drawing which shows the case where it has filled. It is sectional drawing which shows an example of the incident end surface of a bundle fiber. It is sectional drawing which shows an example of arrangement | positioning of the core of a multi-core fiber and bundle fiber, (a) is sectional drawing which shows an example of arrangement | positioning of the core of multi-core fiber, (b) is a cross section which shows an example of arrangement | positioning of the core of bundle fiber FIG. (A)-(e) is a figure which shows the process until the light beam for projection produced | generated in the light source part is projected outside via a multi-core fiber and a light projection part in the said headlamp. . It is a figure which shows the structure of the modification of the said headlamp. It is a figure which shows the structure of another modification of the said headlamp. It is a figure which shows the structure of the headlamp which concerns on another embodiment of this invention. In (a) to (e), in the headlamp, the excitation light beam generated by the light source unit is guided to the light projecting unit by the multi-core fiber, converted into fluorescence, and then projected to the outside. It is a figure which shows the process until. It is a figure which shows the structure of the headlamp which concerns on another embodiment of this invention. It is a figure which shows the structure of the headlamp which concerns on another embodiment of this invention. It is a figure which shows the structure of the headlamp which concerns on another embodiment of this invention. It is the perspective view which looked at the headlamp of FIG. 12 from another viewpoint.

  Here, a headlamp (vehicle headlamp) will be described as an example of the illumination device of the present invention. However, the illuminating device of the present invention may be realized as a headlamp of a vehicle other than an automobile or a moving object (for example, a human, a ship, an aircraft, a submersible craft, a rocket) or other illuminating device. Also good. Examples of other lighting devices include a searchlight, a projector, a home lighting device, a commercial lighting device, and an outdoor lighting device.

  In the following description, the same parts and components are denoted by the same reference numerals. Their names and functions are also the same. Therefore, detailed description thereof will not be repeated.

Embodiment 1
An embodiment of the present invention will be described below with reference to FIGS. The headlamp 1 of this embodiment is an illuminating device that forms a specific light projecting pattern (a desired light projecting pattern).

<Configuration of headlamp 1>
FIG. 1 is a diagram showing the configuration of the headlamp 1. As shown in FIG. 1, the headlamp 1 includes a light source unit (light intensity distribution generation unit) 10, a multi-core fiber 20 (light guide unit), a light projecting unit 30, and a lighting control unit (light intensity distribution generation unit, light intensity distribution). Control unit) 50.

(Light source unit 10)
The light source unit 10 generates light having a light intensity distribution corresponding to the light projecting pattern (referred to as a light beam for projecting light) and causes the light beam for projecting light to enter the incident end face 20 a of the multicore fiber 20. That is, the light source unit 10 generates incident light incident on the incident end face 20a.

  As shown in FIG. 1, the light source unit 10 includes a laser element 11, a heat radiating unit 12, a rising mirror 13, a light emitting unit 14, a support unit 15, an elliptical mirror 16, and a laser light cut filter 17.

(Laser element 11)
The laser element 11 is a light emitting element that functions as an excitation light source that emits laser light as excitation light. As shown in FIG. 1, the light source unit 10 is provided with a plurality of laser elements 11, and laser light is oscillated from each of the plurality of laser elements 11. The laser element 11 may have one light emitting point on one chip, or may have a plurality of light emitting points on one chip.

  By using laser light as the excitation light, it is possible to efficiently excite phosphors included in the light emitting unit 14 described later, and to emit light having a higher brightness than that of the conventional light source, and further, the light emitting unit 14 itself Can be reduced in diameter. Further, since the laser element 11 is a high-intensity light source, it is possible to efficiently narrow the irradiation area formed on the laser light irradiation surface 14a of the light emitting section 14, and as a result, it is possible to project light with a narrow light distribution angle. It becomes.

  The number and arrangement of the laser elements 11 are not particularly limited, and a preferable number of laser elements 11 may be used in a preferable arrangement in order to form a desired light projection pattern.

  The wavelength of the laser light of the laser element 11 is, for example, 395 nm (blue violet) or 450 nm (blue), but is not limited thereto, and may be appropriately selected according to the type of phosphor included in the light emitting unit 14. . For example, the laser element 11 is mounted on a metal package having a diameter of 5.6 mm, and oscillates laser light having a wavelength of 395 nm with an output of 2 W.

  In addition, FIG. 1 shows a configuration in which a plurality of laser elements 11 are evenly arranged on the heat radiating portion 12, but this is not limiting, and the interval between adjacent laser elements 11 may be arbitrarily defined. good.

(Heat dissipation part 12)
The heat radiating unit 12 functions as a heat radiating mechanism that radiates heat from the laser element 11 by receiving heat generated by the laser element 11 from the laser element 11. For this reason, it is preferable to use a metal material (aluminum or the like) having a high thermal conductivity for the heat dissipation part 12.

  Since the light source unit 10 including the heat radiating unit 12 is formed separately from the light projecting unit 30, the light projecting unit 30 can be reduced in size.

(Rising mirror 13)
The rising mirror 13 reflects each of the laser beams emitted from the plurality of laser elements 11 and guides the laser beams to the light emitting unit 14, thereby corresponding to the light projection pattern on the laser light irradiation surface 14 a of the light emitting unit 14. It is an optical member that forms a laser light irradiation pattern (hereinafter simply referred to as an irradiation pattern) having a light intensity distribution. The laser light irradiation surface 14a is a surface that is mainly irradiated with laser light among the surfaces of the light emitting unit 14.

  Specifically, the upright mirror 13 is, for example, an off-axis parabolic mirror, and the plurality of upright mirrors 13 are arranged one-on-one so as to face the light emitting points of the plurality of laser elements 11. . Further, the rising mirror 13 is arranged so that the light emitting point of the laser element 11 is positioned at a substantially focal position of the rising mirror 13.

  The laser light emitted from each of the plurality of laser elements 11 is reflected by the rising mirror 13 to become substantially collimated light, and after the beam width is compressed in the vertical direction, the elliptical mirror 16 is illustrated. It is guided to the light emitting unit 14 through a window portion that is not present.

  The optical path of the laser light emitted from the laser element 11 can be controlled by adjusting the installation angle of the rising mirror 13 and the relative position with the laser element 11, so that a desired irradiation pattern is formed on the laser light irradiation surface 14a. Easy to do. The light projection pattern of the headlamp 1 finally becomes a horizontally long light distribution as shown in FIG. By using the upright mirror 13, the laser light emitted from the laser element 11 can be compressed in the vertical direction, and a horizontally long irradiation pattern can be formed on the laser light irradiation surface 14 a of the light emitting unit 14.

  It is more preferable to use an aspherical mirror that corrects the astigmatic difference of the laser element 11 and produces collimated light as the rising mirror 13. In that case, the collimating property can be further improved. Further, the rising mirror 13 is not limited to this, and may be realized by other parabolic mirrors.

  Although FIG. 1 shows a configuration including the rising mirror 13, the optical member for forming the laser light irradiation pattern is not limited to this, and the rising mirror can also be formed by using a collimating lens and a plane mirror. 13 can be realized. Further, when a collimating lens or a collimating mirror is provided inside the laser element 11 so that collimated light can be emitted from the laser element 11, the rising mirror 13 is changed to a plane mirror. Similar functions can be realized.

(Material of rising mirror 13)
The upright mirror 13 is made by coating AlN ceramic as a material with Al as a reflection film and aluminum oxide as an antioxidant film, but is not limited to this configuration.

For example, as materials, it is desirable to use materials such as BK7, glass such as quartz glass, polycarbonate, acrylic, FRP, SiC, Al ₂ O _{3 and the} like with a small coefficient of thermal expansion, but the final collimation accuracy is not much required. If not, a metal such as Al may be used.

The reflective film is preferably a metal such as Ag or Pt, but may be a reflective film having a multilayer structure such as a SiO ₂ / TiO ₂ multilayer film.

  Further, silicon oxide or the like may be used for the antioxidant film. Note that the antioxidant film is not necessarily coated.

  Further, the surface of the rising mirror 13 may be provided with an increased reflection film (an increased reflection structure such as an HR coat film). In this case, the reflection loss (mirror loss) of the laser beam by the rising mirror 13 can be reduced.

(Light Emitting Unit 14)
The light emitting unit 14 includes a phosphor (fluorescent material) that absorbs laser light and emits fluorescence, and emits fluorescence upon receiving laser light oscillated from the laser element 11.

  For example, the light-emitting portion 14 is formed on a substrate made of a material in which phosphor particles are dispersed (sealing type), a material in which phosphor particles are solidified, or a material having high thermal conductivity. A phosphor containing a phosphor such as (thin film type) coated (deposited) with phosphor particles.

  By using the light emitting unit 14 including such a phosphor, it is possible to generate illumination light with high color rendering properties.

In the present embodiment, the light emitting unit 14 is a rectangle of 2 mm × 0.5 mm, and the phosphor powder is bonded to the inclined portion 15 a of the support unit 15 with TiO ₂ so as to form a thin film with a thickness of 0.1 mm. It is formed by applying as.

  The light emitting unit 14 is disposed near one of the two focal points (first focal point) of the elliptical mirror 16 by the support unit 15. For this reason, the light emitted from the light emitting unit 14 is reflected by the reflection curved surface of the elliptical mirror 16, so that the optical path is controlled.

  The light emitting part 14 is preferably sufficiently small. In this case, the light emitted from the light emitting unit 14 can be efficiently condensed on the other focal point (second focal point) of the elliptical mirror 16.

  Moreover, it is desirable that the light emitting unit 14 is larger than the laser light irradiation pattern.

(Inclined arrangement of the light emitting unit 14)
The light emitting part 14 is inclined and arranged on the inclined part 15a of the support part 15 so that the fluorescence emitted from the light emitting part 14 can be efficiently reflected by the elliptical mirror 16 and controlled. Yes. The inclined portion 15a is configured to be inclined by about 15 ° in the incident direction with reference to a plane perpendicular to the incident direction of the laser beam.

  The light emitted from the light emitting unit 14 has a substantially Lambertian light distribution. Therefore, when the light emitting unit 14 is arranged so that the laser light irradiation surface 14a of the light emitting unit 14 is perpendicular to the incident direction of the laser light, the region with the highest luminous intensity of the light emitted from the light emitting unit 14 is obtained. Since it is located at the window portion of the elliptical mirror 16, the light projecting efficiency deteriorates.

  In consideration of the light projection efficiency, it is desirable that the laser light irradiation surface 14a of the light emitting unit 14 is inclined by about 15 °. However, if the light projection efficiency is not considered, the laser light irradiation surface 14a is The light emitting unit 14 may be arranged so as to be perpendicular to the incident direction.

  Further, when the laser beam is transmitted through the window portion of the elliptical mirror 16 and the light emitted from the light emitting unit 14 is reflected, the manufacturing cost increases, but the laser beam irradiation surface 14a has the laser beam. Even if the light-emitting portion 14 is formed so as to be perpendicular to the incident direction, the light projecting efficiency is improved.

(Type of phosphor)
In the present embodiment, BAM (BaMgAl ₁₀ O ₁₇ : Eu), BSON (Ba) is used as the phosphor of the light emitting unit 14 so as to emit white fluorescence upon receiving laser light having a wavelength of 395 nm oscillated by the laser element 11. ₃ Si ₆ O ₁₂ N ₂ : Eu), Eu-α (Ca-α-SiAlON: Eu), and the like are used in a mixture. However, the phosphor is not limited to these. For example, when the headlamp 1 is used for an automobile, the illumination light of the headlamp 1 has a chromaticity within a predetermined range defined by law. What is necessary is just to select suitably so that it may become white which has. In addition, for applications such as lighting, phosphors may be used alone or a plurality of types of phosphors may be appropriately mixed so that necessary chromaticity is obtained.

For example, other oxynitride phosphors (for example, sialon phosphors such as JEM (LaAl (SiAl) ₆ N ₉ O: Ce) and β-SiAlON), nitride phosphors (for example, CASN (CaAlSiN ₃ : Eu)) Phosphor, SCASN ((Sr, Ca) AlSiN ₃ : Eu) phosphor), Apatite ((Ca, Sr) ₅ (PO ₄ ) ₃ Cl: Eu) system, Silicate ((Ba, Sr, Mg) ₂ SiO ₄ : Eu, Mn) -based phosphor or III-V compound semiconductor nanoparticle phosphor (for example, indium phosphorus: InP).

  In addition, a yellow phosphor (or green and red phosphor) is included in the light-emitting portion 14, and a so-called blue laser having a peak wavelength in a wavelength range of 450 nm (blue) to 450 nm (blue) or 440 nm to 490 nm. White light can also be obtained by irradiating light. In this case, since a part of the laser beam is used as illumination light, the laser beam cut filter 17 is not provided.

(Sealed type)
The sealing material in the case where the light emitting unit 14 is a sealing type is, for example, a resin material such as a glass material (inorganic glass or organic-inorganic hybrid glass) or a silicone resin. Low melting glass may be used as the glass material. The sealing material is preferably highly transparent, and when the laser beam has a high output, a material having high heat resistance is preferable. A structure that is sealed with silicon oxide, titanium oxide, or the like by a sol-gel method may be used.

  An antireflection structure for preventing the reflection of the laser beam may be formed on the upper surface (laser beam irradiation surface 14a) of the light emitting unit 14. In the case of the sealed type, it is particularly desirable to form an antireflection film because it is easy to control the shape of the upper surface of the light emitting portion 14.

(Thin film type)
When the light emitting portion 14 is a thin film type, Al, Cu, AlN ceramic, SiC ceramic, aluminum oxide, Si, or the like is used as the substrate. Note that Al, Ag, BaSO ₄ or the like may be inserted between the substrate and the phosphor for the purpose of improving optical characteristics. After applying or depositing phosphor particles on the substrate, each substrate is divided into a desired size. Then, it fixes to the support part 15 with a high heat conductive adhesive.

  When Al, Cu or the like is used for the substrate, TiN, Ti, TaN, Ta, or the like is coated as a barrier metal on the side where the phosphor particles are not deposited (the side facing the support portion 15). It is desirable. Furthermore, Pt or Au may be coated on the barrier metal.

  Although it is desirable to use eutectic solder such as SnAgCu and AuSn as the high thermal conductive adhesive, it is not limited.

(Supporting part 15)
The support portion 15 made of a metal having high thermal conductivity supports the light emitting portion 14 at the inclined portion 15a at one end thereof, and is connected to the elliptical mirror 16 so that the light emitting portion 14 is positioned at a substantially focal position of the elliptical mirror 16. Has been.

  Although Al is used as the material of the support portion 15 in the present embodiment, high thermal conductive ceramics such as AlN and SiC may be used.

  Moreover, in this Embodiment, the light emission part 14 is being fixed to the support part 15 by apply | coating a fluorescent substance using a titanium oxide as a binder. As this binder, silicon oxide or the like may be used.

  When the light emitting unit 14 is a thin film type, it is desirable to coat TiN, Ti, TaN, Ta, or the like as a barrier metal on the surface of the support unit 15 that faces the light emitting unit 14. Furthermore, Pt or Au may be coated on the barrier metal.

  Note that the other end of the support portion 15 may pass through the elliptical mirror 16 and be connected to a heat radiating member (not shown) having high thermal conductivity. For this reason, the heat of the light emitting portion 14 that generates heat by the laser light propagates to the support portion 15 and the heat radiating member, and is efficiently radiated.

(Elliptical mirror 16)
The elliptical mirror 16 is a reflecting mirror that condenses the fluorescence emitted from the light emitting unit 14 onto the incident end face 20 a of the multicore fiber 20. The elliptical mirror 16 has a part of a curved surface formed when the ellipse is rotated about the symmetry axis of the ellipse as the shape of the reflecting surface. The elliptical mirror 16 has a first focal point on the side on which the laser beam is incident, and the light emitting unit 14 is installed in the vicinity of the first focal point. In addition, the incident end face 20 a of the multicore fiber 20 is located near the second focal point of the elliptical mirror 16.

  With this configuration, the light emitted by the light emitting unit 14 is reflected by the elliptical mirror 16, collected near the second focal point of the elliptical mirror 16, and then guided to the lens 31 by the multicore fiber 20.

  The laser light emitted from the laser element 11 passes through or passes through the window formed in the elliptical mirror 16 and is irradiated on the light emitting unit 14. The window portion may be a through hole or may include a transparent member that can transmit laser light.

(Material of elliptical mirror 16)
In this embodiment, the elliptical mirror 16 is made of FRP as a base material, coated with Al as a reflective film, and further coated with silicon oxide for the purpose of preventing oxidation of Al.

  However, the configuration of the elliptical mirror 16 is not limited to that described above, and any configuration having a light distribution control function may be used. For example, another resin such as acrylic or polycarbonate or a metal member such as Al may be used as the base material, and Ag or Pt may be used as the reflective film. As the antioxidant film, an aluminum oxide-based film or the like may be used, and a film having a function of increasing reflection as a multilayer film of silicon oxide and titanium oxide may be used.

(Laser light cut filter 17)
The laser light cut filter 17 blocks light in a specific wavelength range. In the present embodiment, the laser light cut filter 17 can cut light having a wavelength of 400 nm or less and block laser light having a wavelength of 395 nm emitted from the laser element 11. Therefore, it is possible to prevent the laser light that has not been converted into fluorescence by the light emitting unit 14 from being emitted to the outside of the elliptical mirror 16.

  As a result, it is possible to realize a lighting device that does not project laser light and that is gentle to the human eye. The wavelength to be cut off can be adjusted as appropriate according to the type of the laser light cut filter 17. A wavelength cut filter may be used instead of the laser light cut filter 17.

(Multi-core fiber 20)
A multi-core fiber is an optical fiber in which a plurality of cores are formed in a common cladding. The multi-core fiber 20 guides a light beam for projection having a specific light intensity distribution incident from an incident end face (incident part) 20a while maintaining the light intensity distribution, and emits the light from the exit end face 20b. In order to receive the light beam for projection generated by the light source unit 10, the multi-core fiber 20 is arranged so that the incident end face 20 a (incident pupil) of the multi-core fiber 20 coincides with the second focal point (exit pupil) of the elliptical mirror 16. .

  2A and 2B are views showing the incident end face 20a of the multicore fiber 20. FIG. As shown in FIG. 2, the multi-core fiber 20 includes a plurality of cores 20 c and is included in the clad 20 d so that the cores 20 c do not contact each other. And the coating | coated part 20e has covered the exterior of the clad 20d.

  The core 20c and the clad 20d are made of a material that transmits light, and the refractive index of the core 20c is higher than that of the clad 20d. By adopting such a configuration, light incident on one end face of the core 20c is guided to the other end face of the core 20c by substantially total reflection.

  Since the light propagating through the cores 20c propagates independently of each other (without interfering), the light beam for projection incident on the incident end face 20a has an emission end face without substantially impairing its light intensity distribution. The light is guided to 20b.

  FIG. 2A shows a filling form in which seven cores 20c having the same shape are closely packed in the clad 20d. However, the arrangement of the cores 20c is limited to such a filling form. is not. For example, as shown in FIG. 2B, a core 20c having a horizontally long shape may be filled, or the number of cores 20c may be changed.

  In addition, as for the space | interval of each core 20c, as long as the light which propagates each core can propagate independently is desirable.

  Further, the shape and arrangement of the core may be designed according to the light projection pattern. In the case of FIG. 2B, the elliptical, large circular, and small circular light projection patterns corresponding to the core shape are used. The light is projected to a position according to the arrangement of. The shape of the core is not limited to a circle, but may be a quadrangle or a triangle.

(Bundle fiber)
In place of the multi-core fiber 20, a bundle fiber can be used. The bundle fiber has a configuration in which a plurality of optical fibers are bundled. FIG. 3 is a view showing the incident end face 21 a of the bundle fiber 21. As shown in FIG. 3, the bundle fiber 21 includes a plurality of cores 21c, and each of the cores 21c is separately included in a clad 20d. That is, a plurality of clads 20d including the core 21c are bundled. As the bundle fiber 21, for example, a fiber having a core diameter of 50 μm and a fiber number (core number) of 100 can be used.

  A filler 20f is filled between the clads 20d. Furthermore, the filler 20f is generally made of a material that hardly transmits light. Here, the core 21c and the clad 21d are made of a material that transmits light, and the refractive index of the core 21c is higher than the refractive index of the clad 21d.

  As described above, by adopting the same configuration as that of the multicore fiber 20 shown in FIG. 2A, the light beam for projection incident on the incident end face 21a substantially impairs the light intensity distribution as in the multicore fiber 20. Without being guided, the light is guided to the exit end face opposite to the entrance end face 21a.

(Number of cores in multi-core fiber and bundle fiber)
4A is a cross-sectional view showing the arrangement of the cores 20c of the multicore fiber 20, and FIG. 4B is a cross-sectional view showing the arrangement of the cores 21c of the bundle fiber 21. As shown in FIG. Whether the multi-core fiber 20 or the bundle fiber 21 is used, the light intensity distribution at the incident end face can be more accurately reproduced at the exit end face as the number of cores is larger and the cores are more densely packed. In other words, the higher the proportion of the core in the incident end face, the more faithfully the light pattern on the incident end face can be reproduced on the exit end face.

  The number of the cores 20c in the multi-core fiber 20 is, for example, 100 to 10,000. However, as shown in FIG. 4A, if there are at least two cores 20c, the light intensity distribution at the incident end face 20a is expressed as the outgoing end face. It can be reproduced at 20b. This can also be said for the bundle fiber 21 as shown in FIG.

(Light Projecting Unit 30)
The light projecting unit 30 projects the light beam for projection (emitted light) emitted from the emission end face 20b of the multicore fiber 20 to the outside as illumination light. Since the light source unit 10 and the multi-core fiber 20 are designed so that the luminance invariant is substantially satisfied, the luminance of the light generated in the light source unit 10 is also maintained in the light projecting unit 30. The light projecting unit 30 includes a lens 31.

(Lens 31)
The lens 31 is an optical member that makes the light beam for projection emitted from the emission end face 20 b of the multi-core fiber 20 substantially parallel light and projects the parallel light to the front of the headlamp 1 as illumination light. The substantially parallel light does not need to be completely parallel light, and it is sufficient that the projection angle (vertical angle at which the luminous intensity becomes a half value) is 20 ° or less. The diameter of the lens 31 is 90 mm, for example.

  Further, the emission end face 20b of the multi-core fiber 20 and the focal position of the lens 31 substantially coincide.

(Lighting control unit 50)
The lighting control unit 50 is a control unit that changes the light intensity distribution of incident light incident on the incident end surface 20a of the multicore fiber 20. More specifically, the lighting control unit 50 performs output control (lighting and extinguishing) for each of the plurality of laser elements 11 and controls the position or angle of the rising mirror 13 to thereby control the laser of the light emitting unit 14. The irradiation pattern of the laser beam on the light irradiation surface 14a is formed and changed.

  For example, the lighting control unit 50 changes the light intensity distribution of the incident light incident on the emission end face 20 b of the multicore fiber 20 by changing the irradiation pattern of the laser light emitting unit 14.

  The lighting control unit 50 may be a CPU (central processing unit) that executes instructions of a control program, or may be a logic circuit that executes dedicated processing.

<Function of headlamp 1>
FIG. 5 is a diagram illustrating a process in the headlamp 1 until the light beam for projection generated by the light source unit 10 is projected to the outside through the multi-core fiber 20 and the light projecting unit 30. FIG. 5A shows the configuration of the headlamp 1.

  First, the optical path of the laser light emitted from the laser element 11 is controlled by the rising mirror 13, so that the final light projection is performed on the laser light irradiation surface 14a of the light emitting unit 14 as shown in FIG. An irradiation pattern 40 (laser irradiation spot) having a light intensity distribution corresponding to the pattern is formed. Thereby, the light emitting unit 14 emits fluorescence having a light intensity distribution corresponding to the irradiation pattern.

  This fluorescence is reflected and collected by the elliptical mirror 16 and enters the incident end face 20 a of the multicore fiber 20. At this time, as shown in FIG. 5C, a light pattern 40a substantially similar to the irradiation pattern 40 is formed on the incident end face 20a.

  The light incident on the incident end face 20a is guided through the multi-core fiber 20 and emitted from the outgoing end face 20b. At this time, the light is guided while the intensity distribution of the light incident from the incident end face 20a is maintained. Therefore, the intensity distribution (light pattern 40b) of the light emitted from the emission end face 20b is substantially the same as the light pattern 40a on the incident end face 20a. In FIG. 5, the right and left of the light pattern 40a and the light pattern 40b are reversed, but the viewing direction is different.

  The light emitted from the emission end face 20b is collimated by the lens 31 and projected to the outside, and a projection pattern 41 is formed on the irradiation target (here, the road ahead of the car on which the headlamp 1 is mounted). Is done.

  In this way, by using the multi-core fiber 20, fluorescence having a light intensity distribution corresponding to a desired light projection pattern is generated in the light source unit 10, and the fluorescence is projected as illumination light while maintaining the light intensity distribution. The light can be projected from the unit 30 to the outside.

  Since light having a light intensity distribution corresponding to a desired light projecting pattern is generated in the light source unit 10 formed separately from the light projecting unit 30, the size of the light projecting unit 30 can be reduced. .

(Mechanism to change the projection pattern)
As described above, the irradiation pattern on the laser light irradiation surface 14a of the light emitting unit 14 has a light intensity distribution corresponding to the final projection pattern. Therefore, the projection pattern can be changed by changing the irradiation pattern. Therefore, an example of a mechanism for changing the irradiation pattern will be described below.

  Laser light emitted from the plurality of laser elements 11 is irradiated onto the laser light irradiation surface 14 a of the light emitting unit 14 by the corresponding rising mirror 13. At this time, the irradiation pattern can be changed by changing the inclination of the plurality of upright mirrors 13 and the relative position with the laser element 11. In this configuration, the rising mirror 13 functions as a light intensity distribution control unit that changes the light intensity distribution of incident light incident on the incident end face 20 a of the multicore fiber 20. The rising mirror 13 changes the light intensity distribution of the incident light by changing the irradiation pattern of the laser light emitting section 14.

  The irradiation pattern can also be changed by switching the laser elements 11 that oscillate laser light among the plurality of laser elements 11 (or controlling the output of each laser element 11). In this configuration, the plurality of laser elements 11 may be arranged so that laser light spots can be formed in a matrix on the laser light irradiation surface 14a. In this configuration, since it is not always necessary to adjust the tilt of the rising mirror 13, it is not always necessary to operate the rising mirror 13.

  Further, a lens may be provided in place of the rising mirror 13. This lens is arranged one by one with respect to one laser element 11 so as to face the light emitting point of the laser element 11, and makes the laser light traveling with spreading substantially parallel light. By changing the position of the lens (for example, the distance between the laser element 11 and the lens), the optical path of the laser light emitted from the laser element 11 can be changed, and the irradiation pattern can be changed. .

  The mechanism for changing the irradiation pattern is not limited to that described above, and the laser light irradiation pattern on the laser light irradiation surface 14a may be changed by any mechanism.

  In addition, the change of an irradiation pattern means the change of the light intensity distribution of the laser beam irradiated to the laser beam irradiation surface 14a. Therefore, although the shape of the spot of the laser beam is constant, the irradiation pattern also changes when the light intensity distribution in the spot changes.

(Lighting pattern change style)
The irradiation pattern is changed through the lighting control unit 50. A plurality of light projection patterns (predetermined light projection patterns) are determined in advance as the light projection pattern of the headlamp 1, and the lighting control unit 50 can switch the plurality of predetermined light projection patterns using the above-described mechanism. good. The plurality of predetermined light projection patterns are, for example, a light projection pattern that satisfies a light distribution characteristic standard of a high beam (traveling headlamp), a light projection pattern that satisfies a light distribution characteristic standard of a low beam (passing headlight), and evening The light distribution pattern for nighttime, the light distribution pattern for nighttime, the light distribution pattern for rainy weather, and the light distribution pattern for non-rainy weather.

  Such switching of the predetermined light projection pattern may be performed according to an instruction from the user. Or the detector which detects the change of the environment around the headlamp 1 may be provided, and the lighting control part 50 may switch a predetermined light projection pattern based on the detection result of the said detector.

  The detector is, for example, an external light sensor that detects the brightness around the headlamp 1, and an evening light distribution pattern and a night light distribution pattern are obtained according to the brightness detected by the external light sensor. You may switch. The detector may be a detector other than an optical sensor such as a temperature sensor.

  Further, an object detection device that detects an object in front of (or around) a vehicle on which the headlamp 1 is mounted may be provided, and the light projection pattern may be arbitrarily changed based on the detection result of the object detection device.

  The object detection device, for example, analyzes an image taken by an imaging device (for example, a CCD (charge-coupled device) camera) mounted on a vehicle and detects an object in a light distribution possible area in the image. To do. When an object to be detected is detected, the headlamp 1 changes the light projection pattern based on the coordinates where the object is detected.

  Detected when the object detection device detects, for example, a person, animal, or other vehicle (automobile, motorcycle, or bicycle) that has jumped out ahead of the vehicle, and the object detection device detects these detection targets. The projected pattern may be changed so that illumination light having higher illuminance than other regions is applied to the object that has been applied.

  Further, in a normal state, when a wide light projection pattern that spreads to the maximum area in front of the headlamp 1 is projected and the object detection device detects an oncoming vehicle, only the portion that is projecting to the oncoming vehicle is used. The brightness of the illumination light may be lowered. With this configuration, it is possible to prevent an unpleasant glare from being given to the driver of an oncoming vehicle.

  Furthermore, for example, there is a problem that the center line is particularly difficult to see in the rainy evening. For this reason, the illuminance of the illumination light may be increased only in the portion that is projected onto the center line. In this case, the detection target of the object detection device is a center line. With this configuration, the visibility of the center line in rainy weather can be improved, and the occurrence of accidents can be reduced under the bad weather described above.

<Effect of headlamp 1>
As described above, in the headlamp 1, the light beam for projection having a specific light intensity distribution generated by the light source unit 10 is guided to the light projecting unit 30 by the multi-core fiber 20 while maintaining the light intensity distribution. Light is emitted from the light projecting unit 30 to the outside as substantially parallel light. The light distribution pattern of the illumination light projected from the light projecting unit 30 corresponds to the light intensity distribution of the light beam for projection generated by the light source unit 10.

  Therefore, the headlamp 1 can be made smaller than the conventional configuration in which a plurality of light source units are provided to realize a specific light distribution pattern.

  Moreover, the light projection pattern can be changed by changing the laser light irradiation pattern on the laser light irradiation surface 14 a of the light emitting unit 14. Therefore, the light projection pattern can be changed by a smaller mechanism than the conventional light projection pattern changing mechanism in which the optical axes of the plurality of light source units are changed. In particular, since the light source unit 10 has a mechanism for changing the projection pattern, the projection unit 30 can be downsized.

  Therefore, it is possible to realize a headlamp (illuminating device) that can realize a desired light distribution pattern and can reduce the size of the light projecting unit.

[Modification 1]
<Configuration of headlamp 1A>
FIG. 6 is a diagram for explaining a headlamp 1 </ b> A that is a modification of the headlamp 1. As shown in FIG. 6, the headlamp 1 </ b> A includes a light source unit 10 </ b> A instead of the light source unit 10, unlike the headlamp 1 shown in FIG. 1.

  In the headlamp 1, the elliptical mirror 16 is not necessarily used. As shown in FIG. 6, the headlamp 1 </ b> A includes a hemispherical mirror 16 </ b> A in the light source unit 10 </ b> A instead of the elliptical mirror 16 provided in the light source unit 10 of the headlamp 1. Here, the light emitting portion 14 and the incident end face 20a of the multi-core fiber 20 are arranged at positions that are in an optically conjugate relationship with each other by the hemispherical mirror 16A. By arranging in this way, the light emitted from the light emitting unit 14 can be collected on the incident end face 20a.

[Modification 2]
In the above-described embodiment, the configuration in which the lens 31 is used as the light projecting unit in the light projecting unit 30 has been described. However, a reflecting mirror (reflector) may be used as the light projecting unit.

  FIG. 7 is a diagram for explaining a headlamp 1B which is a modification of the headlamp 1. As illustrated in FIG. 7, the headlamp 1 </ b> B includes a light projecting unit 30 </ b> B instead of the light projecting unit 30, unlike the headlamp 1 illustrated in FIG. 1.

  In the headlamp 1, the lens 31 is not necessarily used. As shown in FIG. 7, the headlamp 1 </ b> B includes an off-axis parabolic mirror 31 </ b> B in the light projecting unit 30 </ b> B instead of the lens 31 provided in the light projecting unit 30 of the headlamp 1.

(Off-axis parabolic mirror 31B)
The off-axis parabolic mirror 31B is an optical member that makes the light beam for projection emitted from the emission end face 20b of the multi-core fiber 20 substantially parallel light and projects the parallel light to the front of the headlamp 1B as illumination light. .

  Further, the emission end face 20b of the multi-core fiber 20 and the focal position of the off-axis parabolic mirror 31B substantially coincide with each other. The opening of the off-axis parabolic mirror 31B is preferably the same as or larger than the numerical aperture (NA) of the emission end face 20b of the multi-core fiber 20.

  Moreover, although the example which uses an off-axis parabolic mirror as a reflecting mirror was demonstrated, an elliptical mirror, a parabolic mirror, a spherical mirror, etc. can also be used and the kind of reflecting mirror is not specifically limited.

[Embodiment 2]
A headlamp 100 according to another embodiment of the present invention will be described below with reference to FIGS. Here, similarly to the headlamp 1, the headlamp 100 is an illumination device that emits illumination light that forms a desired light projection pattern.

<100 configuration of headlamp>
FIG. 8 is a diagram illustrating a configuration of the headlamp 100. As shown in FIG. 8, unlike the headlamp 1 shown in FIG. 1, the headlamp 100 includes a light source unit 110 instead of the light source unit 10 and a light projecting unit 130 instead of the light projecting unit 30.

(Light source unit 110)
Unlike the light source unit 10 shown in FIG. 1, the light source unit 110 does not include the light emitting unit 14, and the laser light emitted from the laser element 11 is not converted into fluorescence and is transmitted to the light projecting unit 130 by the multicore fiber 20. Light is guided.

  Specifically, the laser light emitted from the laser element 11 is subjected to light distribution control by the rising mirror 13, and an excitation light bundle that is excitation light having a light intensity distribution corresponding to the light projection pattern is generated. The generated excitation beam bundle is condensed on the incident end surface 20 a of the multi-core fiber 20 by the condenser lens 111. The condensed excitation light propagates inside the multi-core fiber 20 and is emitted from the emission end face 20b.

(Condenser lens 111)
The condensing lens 111 is an optical member that condenses the laser light emitted from the laser element 11 and controlled to be reflected and distributed by the rising mirror 13 onto the incident end face 20a. The condensing lens 111 condenses the laser light by receiving the laser light from one surface and transmitting and refracting it. Here, the incident end face 20a of the multicore fiber 20 and the focal position of the condensing lens 111 substantially coincide.

(Light Projecting Unit 130)
The light projecting unit 130 projects light (fluorescence) obtained by wavelength-converting laser light (emitted light) emitted from the emission end face 20 b of the multicore fiber 20 to the outside. The light projecting unit 130 includes an imaging lens 131, a parabolic mirror 132, a light emitting unit 14, a support unit 15, and a laser light cut filter 17. In addition, the light projecting unit 130 receives the excitation light beam emitted from the emission end surface 20 b of the multicore fiber 20 in the imaging lens 131.

(Imaging lens 131)
The imaging lens 131 is disposed between the emission end face 20b of the multi-core fiber 20 and the light emitting portion 14, and condenses the excitation light beam emitted from the emission end face 20b on the laser light irradiation surface 14a of the light emission portion 14. By doing so, a light pattern corresponding to the light intensity distribution of the excitation light beam is imaged. The formed light pattern is referred to as an irradiation pattern.

  Here, the emission end face 20 b and the light emitting unit 14 of the multicore fiber 20 are arranged at positions that are in an optically conjugate relationship with each other by the imaging lens 131. By arranging in this way, the excitation light beam emitted from the emission end face 20 b of the multi-core fiber 20 can be imaged on the laser light irradiation surface 14 a of the light emitting unit 14.

(Parabolic mirror 132)
The parabolic mirror 132 controls the light distribution of the fluorescence emitted by the light emitting unit 14 by receiving the excitation light bundle, and projects the light toward the outside, thereby forming a specific light projection pattern. The light emitting unit 14 is disposed at a substantially focal position of the parabolic mirror 132.

  The parabolic mirror 132 may be, for example, a member having a metal thin film formed on the surface thereof or a metal member.

  The parabolic mirror 132 is at least a part of a partial curved surface obtained by cutting a curved surface (parabolic curved surface) formed by rotating the parabola about the axis of symmetry of the parabola with a plane including the rotational axis. Is included in the reflective surface.

  Part of the parabolic mirror 132 having such a shape is disposed so as to face the laser light irradiation surface 14 a of the light emitting unit 14. If it demonstrates from another viewpoint, when it sees from the light emission part 14, at least one part of the parabolic mirror 132 will be arrange | positioned in the radiation angle where the luminous intensity of the light emitted from the light emission part 14 is the highest.

  By making the positional relationship between the light emitting unit 14 and the parabolic mirror 132 as described above, it is possible to efficiently project the fluorescence of the light emitting unit 14 within a predetermined solid angle. Can be increased.

<Functions of the headlamp 100>
FIG. 9 shows a state in which in the headlamp 100, the excitation light beam generated by the light source unit 110 is guided to the light projecting unit 130 by the multi-core fiber 20 and converted into fluorescence, and then projected to the outside. It is a figure which shows a process. FIG. 9A shows the configuration of the headlamp 100.

  First, the optical path of the laser light emitted from the laser element 11 is controlled by the rising mirror 13. Further, the laser beam is condensed by the condenser lens 111 and is incident on the incident end face 20 a of the multi-core fiber 20. At this time, as shown in FIG. 9B, the light pattern 40a is formed on the incident end face 20a. The light pattern 40a has a light intensity distribution corresponding to the light projection pattern.

  The laser light incident on the incident end face 20a is guided through the multi-core fiber 20 and emitted from the emission end face 20b. At this time, the intensity distribution of the laser beam incident from the incident end face 20a is guided while being maintained. Therefore, the intensity distribution (light pattern 40b) of the laser light emitted from the emission end face 20b is substantially the same as the light pattern 40a on the incidence end face 20a.

  The laser light emitted from the emission end face 20 b is imaged on the laser light irradiation surface 14 a of the light emitting unit 14 by the imaging lens 131. As a result, as shown in FIG. 9D, an irradiation pattern 40 (laser irradiation spot) having a light intensity distribution corresponding to the final projection pattern is formed on the laser light irradiation surface 14a. Thereby, the light emitting unit 14 emits fluorescence having a light intensity distribution corresponding to the irradiation pattern 40.

  This fluorescence is reflected by the parabolic mirror 132 and is made into substantially parallel light and projected to the outside, and the projection pattern 41 is projected on the irradiation target (here, the road ahead of the car on which the headlamp 100 is mounted). It is formed.

  The mechanism for changing the projection pattern is the same as that of the headlamp 1.

<Effect of headlamp 100>
As described above, the headlamp 100 generates the excitation light beam having the light intensity distribution corresponding to the desired light projection pattern in the light source unit 110, and maintains the light intensity distribution of the generated excitation light beam. The multi-core fiber 20 is guided to the light projecting unit 130 as it is. Then, in the light projecting unit 130, the excitation light bundle is converted into fluorescence and projected to the outside. Therefore, the illumination light projected from the light projecting unit 130 forms a desired light projecting pattern.

  Therefore, a small headlamp can be realized as compared with the conventional configuration in which a plurality of light source units are provided to realize a specific light distribution pattern.

  Further, the light projection pattern can be changed by changing the light intensity distribution of the laser light incident on the incident end face 20a of the multi-core fiber 20. Since the mechanism for changing the projection pattern is provided in the light source unit 10, the projection unit 130 can be downsized.

[Embodiment 3]
The following will describe still another embodiment of the present invention with reference to FIG. Similarly to the headlamp 1, the headlamp 200 is an illumination device that emits illumination light that forms a specific light projection pattern.

<Configuration of headlamp 200>
FIG. 10 is a diagram illustrating a configuration of the headlamp 200. Here, as compared with the headlamp 100 shown in FIG. 8, the headlamp 200 includes a light projecting unit 230 instead of the light projecting unit 130 as shown in FIG. 10.

(Light Projecting Unit 230)
The light projecting unit 230 includes a light emitting unit 231, a housing 232, a light projecting lens 233, and a laser light cut filter 17. Further, the light projecting unit 230 includes a part of the multi-core fiber 20 on the emission end face 20 b side, and the emission end face 20 b of the multi-core fiber 20 is disposed in a position close to or in contact with the light emitting unit 231.

(Light Emitting Unit 231)
By the way, in the above-mentioned headlamp 100, the laser beam emitted from the laser element 11 is irradiated to the light emitting unit 14, and the fluorescence is mainly emitted to the side where the laser element 11 is located. Such a light emitting unit 14 is referred to as a “reflective light emitting unit” in the present application.

  On the other hand, in the headlamp 200 of the present embodiment, the laser light emitted from the laser element 11 is irradiated on the laser light irradiation surface of the light emitting portion as the light emitting portion 231, and the fluorescence is opposite to the laser light irradiation surface. A light emitting part of the type mainly emitted is used. Such a light emitting unit is referred to as a “transmissive light emitting unit” in the present application.

In the case of using a transmissive light emitting unit, it is preferable to control the amount of excitation light and fluorescence transmitted through the light emitting unit. That is, in the transmissive light emitting part, it is preferable to lower the distribution density of the phosphor particles to such an extent that the light emitting performance is not impaired as compared with the reflective light emitting part. In addition, it is also effective for controlling the amount of transmitted light to mix fine particles with little light absorption in the visible light region, such as SiO ₂ particles, as the phosphor contained in the light emitting part.

(Housing 232)
The housing 232 is a case that includes the light emitting unit 231, the light projecting lens 233, and the laser light cut filter. The housing 232 is not a reflector such as the parabolic mirror 132 provided in the light projecting unit 130 of the headlamp 100.

(Projection lens 233)
The light projection lens 233 receives the light emitted from the light emitting unit 231, transmits and refracts it, converts the light into substantially parallel light, and projects the light to the outside.

  Here, the function of the headlamp 200 and the mechanism for changing the light projection pattern are the same as those of the headlamp 100.

<Effect of headlamp 200>
As described above, the headlamp 200 uses the transmissive light emitting unit 231 and the light projecting lens 233 in combination. Even when such a configuration is used, a small light projecting unit can be realized as in the case of using a reflective light emitting unit.

  Further, by using the transmissive configuration as described above, it is possible to form a light projection pattern with suppressed edge sharpness. The projection pattern is effective, for example, when it is desired to dimly illuminate a wide area.

[Embodiment 4]
A further embodiment of the present invention will be described below with reference to FIG. Similarly to the headlamp 1, the headlamp 300 is an illumination device that emits illumination light that forms a specific light projection pattern. As will be described later, the headlamp 300 can be classified as a headlamp in which the light source section includes a light emitting section (phosphor) and the laser light irradiation form is a scan type.

<Configuration of headlamp 300>
FIG. 11 is a diagram illustrating a configuration of the headlamp 300. Here, as compared with the headlamp 1 shown in FIG. 1, the headlamp 300 includes a light source unit 310 instead of the light source unit 10 as shown in FIG. 11.

(Light source unit 310)
The light source unit 310 includes a light guide control unit 311, a MEMS (Micro Electro Mechanical System) mirror 312, and a MEMS mirror support unit 313 instead of the rising mirror 13 of the light source unit 10. Below, the structure of the light source part 310 is demonstrated by comparing with the light source part 10. FIG.

  First, the light source unit 10 includes a plurality of laser elements 11, and the lighting control unit 50 controls the lighting of the plurality of laser elements 11. Next, the rising mirror 13 reflects and guides the laser beams emitted from the plurality of laser elements 11 to the light emitting unit 14. Thus, the light source unit 10 forms an irradiation pattern having a light intensity distribution corresponding to the final light projection pattern on the laser light irradiation surface 14 a of the light emitting unit 14.

  On the other hand, unlike the light source unit 10, the light source unit 310 first guides the laser light emitted from the laser element 11 to the MEMS mirror 312. Next, the MEMS mirror 312 reflects the laser light guided from the light guide control unit 311 and guides it to the light emitting unit 14.

  Here, as will be described later, the MEMS mirror 312 can irradiate a laser beam to an arbitrary place on the laser beam irradiation surface 14 a of the light emitting unit 14. That is, since the laser beam irradiation form can be a scan type, the light source unit 310 does not necessarily require a plurality of laser elements 11 unlike the light source unit 10.

  That is, in the light source unit 310, the number of laser elements 11 can be reduced as compared with the light source unit 10 by adopting a scan type irradiation of the laser light to the light emitting unit 14.

(Light guide controller 311)
The light guide control unit 311 is a control unit for guiding the laser light emitted from the laser element 11 to the MEMS mirror 312. Here, the light guide controller 311 sets the energy intensity distribution of the laser light emitted from the laser element 11 to a top hat distribution. As the light guide control unit 311, for example, an optical rod, a multimode fiber, or the like can be used.

  In addition, the light guide control unit 311 may further include a lens.

(MEMS mirror 312)
The MEMS mirror 312 is a mirror that includes a micromirror that is a combination of a mechanical component and an electronic circuit to form a microcomponent. The MEMS mirror 312 reflects the laser beam emitted from the light guide control unit 311 and emits the laser beam from the light emitting unit 14. Irradiation is performed on the irradiation surface 14a.

  Here, in the MEMS mirror 312, the minute mirror is controlled by the MEMS mirror drive control unit 350. That is, the laser light emitted from the laser element 11 is controlled by the light guide control of the laser light to the MEMS mirror 312 by the light guide control unit 311 and the drive control of the micro mirror of the MEMS mirror 312 by the MEMS mirror drive control unit 350. It is possible to irradiate an arbitrary place on the laser light irradiation surface 14 a of the light emitting unit 14. Thereby, the irradiation position of the laser beam to the incident end face 20a of the multi-core fiber 20 can be changed and scanned (scanned).

  That is, since the laser beam irradiation form can be a scan type, the light source unit 310 does not necessarily need to use a plurality of laser elements 11 unlike the light source unit 10 by using the MEMS mirror 312 or the like. Moreover, the irradiation pattern of the laser beam formed on the laser beam irradiation surface 14a of the light emitting unit 14 can be easily changed by changing the position or angle of the micro mirror of the MEMS mirror 312 using software.

  The mirror surface of the micro mirror of the MEMS mirror 312 may be coated with Al coating or the like.

(Control of MEMS mirror 312)
The micro mirror of the MEMS mirror 312 is, for example, an in-plane direction in which the MEMS mirror 312 is installed, and changes an angle in the X axis direction perpendicular to the gravity direction and / or the Y direction perpendicular to the direction, The irradiation pattern of the laser beam applied to the laser beam irradiation surface 14a of the light emitting unit 14 is changed by the change in the angle. That is, the minute mirror of the MEMS mirror 312 changes the irradiation position of the laser light irradiated to the light emitting unit 14.

  The MEMS mirror 312 is preferably set such that the drive range is wider in the Y-axis direction than in the X-axis direction. This is particularly effective when the light projection range of the headlamp 300 is horizontally long. On the other hand, when the light projection range of the headlamp 300 is vertically long, the MEMS mirror 312 is set so that the drive range is wider in the X-axis direction than in the Y-axis direction. It may be changed as appropriate.

  Further, in the case where the light projection pattern is formed by continuously scanning the laser beam and synchronizing the intensity of the laser beam with the scanning speed, it is desirable to use a resonant MEMS mirror that can increase the scanning speed. .

  For example, when scanning at a vertical scanning speed of 60 Hz and synchronizing the intensity of the laser light with the scanning speed, the light emitting unit 14 is used to form a light emission pattern that is a light projection pattern of a passing lamp. It is desirable to use a resonance type.

  On the other hand, when this system is used in a usage such as changing the light projection position of a spotlight, if you continue to illuminate an object (for example, a deer that is a risk factor), it is better to illuminate the object continuously. It is desirable to use a non-resonant type MEMS mirror (if the output of the laser beam is the same), since the illuminance at the object becomes high.

(MEMS mirror support 313)
The MEMS mirror support portion 313 is a member for supporting the MEMS mirror 312. Here, the MEMS mirror support unit 313 moves the MEMS mirror 312 at a predetermined position so that the MEMS mirror 312 can reflect the laser light emitted from the laser element 11 via the light guide control unit 311 toward the light emitting unit 14. Or the angle is fixed.

(MEMS mirror drive controller 350)
The MEMS mirror drive control unit 350 is a control unit for controlling the position or angle of a micromirror included in the MEMS mirror 312. More specifically, the MEMS mirror drive control unit 350 controls the position or angle of the minute mirror of the MEMS mirror 312 to form and change the laser light irradiation pattern on the laser light irradiation surface 14a of the light emitting unit 14. .

  For example, the MEMS mirror drive control unit 350 changes the light intensity distribution of the incident light incident on the emission end face 20 b of the multicore fiber 20 by changing the irradiation pattern of the laser light emitting unit 14.

  The MEMS mirror drive control unit 350 may be a CPU that executes an instruction of a control program, or may be a logic circuit that executes a dedicated process.

<Effect of headlamp 300>
As described above, the headlamp 300 can reduce the number of the laser elements 11 by using the light guide control unit 311 and the MEMS mirror 312 to scan the light emitting unit 14 with laser light. . Moreover, the irradiation pattern of the laser beam formed on the laser beam irradiation surface 14a of the light emitting unit 14 can be easily changed by changing the position or angle of the micro mirror of the MEMS mirror 312 using software.

  In this embodiment, a laser beam is scanned using a MEMS mirror or the like. However, the present invention is not limited to this configuration, and a solenoid actuator or the like may be used.

[Embodiment 5]
The following will describe still another embodiment of the present invention with reference to FIGS. Similarly to the headlamp 1, the headlamp 400 is an illumination device that emits illumination light that forms a specific light projection pattern. As will be described later, the headlamp 400 includes a light emitting section (phosphor) in the light projecting section and can be classified into a headlamp whose laser beam irradiation form is a scan type.

<Configuration of headlamp 400>
FIG. 12 is a diagram illustrating a configuration of the headlamp 400. Compared with the headlamp 100 shown in FIG. 8, the headlamp 400 includes a light source unit 410 and a condensing lens drive control unit 450 in place of the light source unit 110, as shown in FIG.

(Light source unit 410)
The light source unit 410 mainly includes a condensing lens 411 driven by a solenoid actuator in place of the condensing lens 111 of the light source unit 110. Hereinafter, the configuration of the light source unit 410 will be described by comparing with the light source unit 110.

  First, the light source unit 110 includes a plurality of laser elements 11, and the lighting control unit 50 controls the lighting of the plurality of laser elements 11. Next, the rising mirror 13 reflects each of the laser beams emitted from the plurality of laser elements 11 and guides them to the incident end face 20 a of the multicore fiber 20 via the condenser lens 111. Next, the laser light is guided by the multi-core fiber 20, emitted from the emission end face 20 b, and finally irradiated to the light emitting unit 14 of the light projecting unit 130.

  On the other hand, in the light source unit 410, unlike the light source unit 110, the condenser lens 411 driven by a solenoid actuator guides the laser light emitted from the laser element 11 to the incident end face 20 a of the multicore fiber 20. Yes. Next, the laser light is guided by the multi-core fiber 20, emitted from the emission end face 20 b, and finally irradiated to the light emitting unit 14 of the light projecting unit 130.

  Here, as will be described later, the condensing lens 411 can finally irradiate laser light to an arbitrary place on the laser light irradiation surface 14 a of the light emitting unit 14. That is, since the laser light irradiation form can be a scan type, the light source unit 410 does not necessarily require a plurality of laser elements 11 unlike the light source unit 110.

  That is, in the light source unit 410, the number of the laser elements 11 can be reduced as compared with the light source unit 110 by using the scan type irradiation of the light emitting unit 14 in the light projecting unit 130.

(Condensing lens 411)
The condensing lens 411 is an optical element that condenses the laser light emitted from the laser element 11 onto the incident end face 20 a of the multicore fiber 20. The condensing lens 111 condenses the laser light by receiving the laser light from one surface and transmitting and refracting it. Here, the incident end face 20a of the multicore fiber 20 and the focal position of the condensing lens 411 substantially coincide with each other. The condenser lens 411 is driven by a solenoid actuator. Thereby, the condensing position of the laser beam to the incident end surface 20a of the multi-core fiber 20 can be changed, and finally the irradiation pattern on the laser beam irradiation surface 14a of the light emitting unit 14 of the light projecting unit 130 is changed. Can be made.

  That is, since the laser beam irradiation form can be a scan type, the light source unit 410 does not necessarily require a plurality of laser elements 11 unlike the light source unit 110 by using the condenser lens 411 and the solenoid actuator. .

  As described above, the condensing lens 411 is controlled by the condensing lens drive control unit 450 via the solenoid actuator. Hereinafter, the control will be described in detail.

(Control of condensing lens 411)
FIG. 13 is a diagram illustrating a configuration in which the condenser lens 411 is controlled by the solenoid actuator 412. FIG. 13 is a perspective view of the headlamp 400 shown in FIG. 12 as seen from another viewpoint. As shown in FIG. 13, the condenser lens 411 is attached to a solenoid actuator 412 so that the position and angle can be controlled.

  The solenoid actuator 412 may include, for example, a coil, a magnet, a suspension wire, and a housing that supports these.

  In the example shown in FIG. 13, the shape of the solenoid actuator 412 is a rectangular shape, but is not limited to this, and can be various shapes.

  In the above-described configuration, a magnetic field is generated by passing a current through the coil, and a rotational force (rotational torque) is applied to the magnet by the magnetic field. Therefore, the rotational torque can be freely changed by changing the magnitude of the current. Thereby, the operation of the housing can be controlled. That is, the operation of the condenser lens 411 installed on the solenoid actuator 412 can be controlled. Further, by changing the direction of the current flowing through the coil, the direction of the rotational force acting on the magnet can be changed in the opposite direction.

  Accordingly, the condensing lens 411 can freely operate in the direction of the arrow shown in FIG. 12, so that the relative position of the condensing lens 411 with respect to the incident end surface 20 a of the multicore fiber 20 changes, and finally the light projection The irradiation position of the laser beam in the light emitting unit 14 of the unit 130 can be changed.

  The solenoid actuator 412 may be of another type as long as it has a mechanism for operating the condensing lens 411 in the direction of the arrow shown in FIG. 12, for example, “rack and pinion type” or helicoid type.

(Heat dissipation part 420)
The heat radiating section 420 functions as a heat radiating mechanism that radiates heat from the laser element 11 by receiving heat generated by the laser element 11 from the laser element 11. For this reason, it is preferable to use a metal material (such as aluminum) having a high thermal conductivity for the heat radiating portion 420. Further, as shown in FIG. 12, the heat radiating section 420 may have a fin shape on a part of the surface in order to increase the surface area in contact with a cooling medium such as the atmosphere.

  Since the light source unit 410 including the heat radiating unit 420 is formed separately from the light projecting unit 130, the light projecting unit 130 can be reduced in size.

(Condensing lens drive controller 450)
The condensing lens drive control unit 450 is a control unit for controlling the position or angle of the condensing lens 411 via the solenoid actuator 412. More specifically, the condensing lens drive control unit 450 controls the position or angle of the condensing lens 411 via the solenoid actuator 412, thereby determining the light intensity distribution of the laser light on the incident end surface 20 a of the multicore fiber 20. Form and change. Thereby, the light intensity distribution of the outgoing light emitted from the outgoing end face 20b of the multi-core fiber 20 is changed, and finally the irradiation pattern of the laser light applied to the light emitting unit 14 of the light projecting unit 130 is changed.

  The condenser lens drive control unit 450 may be a CPU that executes a command of a control program, or may be a logic circuit that executes a dedicated process.

<Effect of headlamp 400>
As described above, the headlamp 400 uses the condensing lens 411 and the solenoid actuator 412 to change the number of the laser elements 11 to the light emitting unit 14 of the light projecting unit 130 by using a scan type. Can be reduced.

  In this embodiment, a laser beam is scanned using a solenoid actuator or the like, but the present invention is not limited to this configuration, and a MEMS mirror or the like may be used.

[Additional Notes]
The present invention is not limited to the above-described embodiments, and various modifications can be made within the scope shown in the claims. That is, embodiments obtained by combining technical means appropriately modified within the scope of the claims are also included in the technical scope of the present invention.

  The present invention can be suitably applied to an illumination device that emits illumination light having a specific light projection pattern, particularly a headlamp for a vehicle or the like.

1 Headlamp (lighting device, vehicle headlamp)
1A Headlamp (lighting device, vehicle headlamp)
1B Headlamp (lighting device, vehicle headlamp)
DESCRIPTION OF SYMBOLS 10 Light source part 10A Light source part 14 Light emission part 16 Elliptical mirror (condensing part)
16A spherical mirror (condenser)
20 Multi-core fiber (light guide)
20a Incident end face (incident part)
20b Output end face (output part)
21 Bundle fiber (light guide)
21a Incident end face (incident part)
30 light projection part 40 irradiation pattern 50 lighting control part (light intensity distribution generation part, light intensity distribution control part)
100 headlamps (lighting devices, vehicle headlamps)
DESCRIPTION OF SYMBOLS 110 Light source part 130 Light projection part 200 Headlamp (illuminating device, vehicle headlamp)
230 Light Emitting Unit 231 Light Emitting Unit 300 Head Lamp (Lighting Device, Vehicle Headlamp)
400 Headlamp (lighting device, vehicle headlamp)

Claims (10)

A light bundle composed of a plurality of incident light incident from the incident section , and guides the light bundle having a specific light intensity distribution while maintaining the light intensity distribution, and a light guide section that emits from the output section;
A light source unit including a light source and a mirror that generates the incident light incident on the incident unit by reflecting the light emitted from the light source;
A light projecting unit that projects the emitted light emitted from the emitting unit or the light converted from the emitted light to the outside ;
A light intensity distribution controller that changes the light intensity distribution of the light flux by changing the light intensity and optical path of each incident light by controlling the output or the angle of the mirror while controlling the output of the light source. When,
A lighting device comprising:   The mirror is a MEMS mirror including a micro mirror formed by fusing a mechanical part and an electronic circuit to form a fine part,
  The light intensity distribution control unit changes the light intensity distribution of the light flux by changing the light intensity and the optical path of each incident light by controlling the position or angle of the micromirror. The lighting device according to claim 1.   The light source unit includes a plurality of the mirrors,
  The light intensity distribution control unit changes a light intensity and an optical path of each incident light by controlling a position or an angle of each mirror, and changes the light intensity distribution of the light beam. The lighting device according to claim 1. The light source unit includes a light emitting unit that emits fluorescence in response to excitation light,
The light source emits the excitation light,
The mirror irradiates the light emitting part by reflecting the excitation light, generates the fluorescence as the incident light incident on the incident part,
The said light intensity distribution control part changes the light intensity distribution of the said light bundle by changing the irradiation pattern in the said light emission part of the said excitation light, The any one of Claims 1-3 characterized by the above-mentioned. Lighting equipment. The light source part is
A light emitting section that emits fluorescence in response to excitation light;
The illumination apparatus according to claim 1, further comprising a condensing unit that condenses the fluorescence emitted from the light emitting unit as the incident light on the incident unit.   The illumination device according to claim 5, wherein the light collecting unit is an elliptical mirror. A light emitting part that emits fluorescence in response to excitation light is further provided,
The light guide part emits the excitation light from the emission part as the emitted light,
The lighting device according to claim 1, wherein the light projecting unit projects fluorescence emitted from the light emitting unit.   The lighting device according to claim 1, wherein the light guide is a multi-core fiber.   The lighting device according to claim 1, wherein the light guide unit is a bundle fiber. Vehicle headlamp comprising a lighting device according to any one of claims 1-9.

Images