JP6719261B2 - Lighting device and vehicle headlight - Google Patents

Description

The present invention relates to a lighting device and a vehicle headlamp including a light emitting unit that emits fluorescence upon receiving excitation light emitted from an excitation light source, and a light projecting unit that emits light emitted from the light emitting unit.

A semiconductor light emitting element such as a light emitting diode (LED) or a semiconductor laser (LD) is used as an excitation light source, and the excitation light generated from these excitation light sources is applied to a light emitting unit including a phosphor. A lighting device that emits light emitted from a light emitting unit via a light projecting unit is conventionally known. For example, in Patent Document 1, a fixed light source that emits light of a predetermined wavelength, a phosphor unit, a light projecting unit including a lens system, and a range and/or intensity distribution of excitation light to the phosphor unit are changed. A light source device including a light control unit for controlling the light source is described. The light source device described in Patent Document 1 guides the light emitted from the light source device to the light projecting section by the light control means.

JP 2011-134619 A (Published July 7, 2011)

However, in the conventional technique as described above, as a problem peculiar to the laser, light including stray light from a fixed light source or light specularly reflected by the phosphor portion is emitted to the outside through the light emitting portion. there is a possibility. If stray light or light specularly reflected by the phosphor part is included in the projected light, for example, the color of the light of the fixed light source becomes strong, and the projected light has uneven color. There is.

The present invention has been made in view of the above problems, and an object thereof is to reduce stray light and excitation light from an excitation light source that is specularly reflected in a light emitting unit, which is included in light to be emitted. It is to realize an illuminating device that suppresses uneven color of emitted light.

In order to solve the above problems, the illumination device according to an aspect of the present invention is an excitation light source that emits excitation light, a light emitting unit that emits fluorescence by receiving excitation light emitted from the excitation light source, The light emitting unit includes a light projecting unit that projects light emitted from the light emitting unit, and a light shielding unit that is provided between the light emitting unit and the light projecting unit. Is a cylindrical hollow member that covers the light emitting portion, the end portion of the light shielding portion on the light emitting portion side is on a straight line connecting the end portion of the light emitting portion and the center of the light emitting portion, An angle formed by a straight line connecting an end portion and the center of the light emitting portion and a perpendicular line of the light emitting portion passing through the center of the light emitting portion is equal to or less than an incident angle of the excitation light to the light emitting portion. To do.

According to one embodiment of the present invention, stray light and excitation light from the excitation light source that is specularly reflected in the light emitting portion, which are included in the emitted light, are reduced, and an effect of suppressing color unevenness of the emitted light is exerted. ..

(A) is a schematic diagram which shows the schematic structure of the illuminating device which concerns on Embodiment 1 of this invention, (b) is the top view which looked at the light-shielding part of the said illuminating device from the light projection lens side. It is a figure explaining an example of the effect of the said illuminating device. It is a figure explaining the other example of the effect of the said illuminating device. (A) And (b) is a figure explaining reduction of the color unevenness by the above-mentioned illuminating device. (A)-(d) is a figure which shows the modification of the light-shielding part in the said illuminating device. It is a schematic diagram which shows schematic structure of the illuminating device which concerns on Embodiment 2 of this invention. It is a schematic diagram which shows schematic structure of the illuminating device which concerns on Embodiment 3 of this invention. It is a figure explaining an example of the effect of the said illuminating device. It is a schematic diagram which shows schematic structure of the illuminating device which concerns on Embodiment 4 of this invention.

Hereinafter, embodiments of the present invention will be described in detail. For convenience of explanation, members having the same functions as those shown in the embodiments will be designated by the same reference numerals, and the description thereof will be omitted as appropriate.

[Embodiment 1]
The first embodiment of the present invention will be described with reference to FIGS.

(Structure of lighting device)
The configuration of the illumination device 100 of this embodiment will be described based on FIG. 1. FIG. 1A is a schematic diagram showing a schematic configuration of a lighting device 100 according to the first embodiment of the present invention, and FIG. 1B is a view showing a light shielding unit 130 of the lighting device 100 from a light projecting lens 140 side. FIG.

As shown in FIG. 1A, the lighting device 100 includes a laser element 110, a light emitting section 120, a light blocking section 130, and a light projecting lens 140. The illumination device 100 is a device that can project an object from the light projecting lens 140, and is used, for example, as a vehicle headlight.

The laser element 110 (excitation light source) emits laser light R (excitation light). The laser light R is incident on the light emitting unit 120 at an incident angle θ. The number of laser elements 110 may be one or more. When the plurality of laser elements 110 are provided, the laser light as the laser light R is emitted from each of the plurality of laser elements 110. By using a plurality of laser elements 110, it is possible to easily obtain high-power laser light R.

The laser element 110 may have one light emitting point on one chip, or may have a plurality of light emitting points on one chip. The wavelength of the laser light R can be, for example, 405 nm (blue violet) or 450 nm (blue). The wavelength of the laser light is not limited to the above, and may be appropriately selected according to the type of phosphor contained in the light emitting unit 120. As the laser element 110, for example, a semiconductor laser can be used. A light emitting diode (LED) may be used as the excitation light source instead of the laser element 110.

The light emitting unit 120 receives the laser light R emitted from the laser element 110, emits fluorescence, and emits light. The light emitting section 120 includes a fluorescent substance (fluorescent substance) that emits fluorescence when excited by the laser light R. When the laser light R is incident from the laser element 110, the light emitting unit 120 converts a part of the incident laser light R into fluorescence. The light emitting unit 120 diffuses the fluorescent light and the laser light R that has not been converted into the fluorescent light and emits the diffused light to the surroundings.

The light emitting unit 120 may be, for example, one in which phosphor particles are dispersed inside a sealing material, one in which phosphor particles are solidified, or phosphor particles on a substrate made of a material having high thermal conductivity. It is possible to use a material obtained by depositing Since the light emitting section 120 converts the laser light R into fluorescence, it can be said that the light emitting section 120 is a wavelength conversion element.

The light projecting lens 140 (light projecting unit) projects the light emitted by the light emitting unit 120. Specifically, the light projecting lens 140 is arranged so as to face the light emitting unit 120. The light projecting lens 140 transmits the light emitted by diffusing the fluorescent light and the laser light R not converted into fluorescent light by the light emitting unit 120, and projects the light toward the outside of the lighting apparatus 100.

In this embodiment, the light projecting lens 140 is a circular convex lens, and the center line of the light projecting lens 140 coincides with the perpendicular line P passing through the center C of the light emitting unit 120. The center C of the light emitting unit 120 means the center C of the surface of the light emitting unit 120 on the light projecting lens 140 side. Therefore, the angle formed by the straight line L connecting the end 140a of the light projecting lens 140 and the center C of the light emitting unit 120 and the perpendicular P is constant. The light projecting lens 140 is made of, for example, glass or resin.

Although not shown, the lighting device 100 further includes a cover that covers the light shielding unit 130. The cover may be provided, for example, like the cover 160 shown in FIG. 9.

(Shading part)
The light blocking unit 130 is a tubular member that is provided between the light emitting unit 120 and the light projecting lens 140 and blocks light on the outer surface 130d. The light blocking portion 130 covers the end portion 140a of the light projecting lens 140, and the end portion (lower end portion 130b) of the light blocking portion 130 on the light emitting portion 120 side connects the end portion 140a of the light projecting lens 140 and the center C of the light emitting portion 120. The angle formed by the straight line L and the perpendicular P of the light emitting portion 120 which is on the straight line L and passes through the center C of the light emitting portion 120 is equal to or smaller than the incident angle θ of the laser light R to the light emitting portion 120. is there. This will be specifically described below.

As shown in FIGS. 1A and 1B, the light shielding portion 130 is a hollow cylindrical member and penetrates from the light projecting lens 140 side to the light emitting portion 120 side. Further, the light blocking portion 130 covers the end portion 140 a of the light projecting lens 140. In other words, the upper end 130a of the light shield 130 on the light projecting lens 140 side covers the end 140a of the light projecting lens 140. The light shielding portion 130 covering the end portion 140a means, for example, (1) that the outer diameter of the upper end portion 130a is equal to or larger than the outer diameter of the end portion 140a, and (2) the upper end portion 130a is connected to the end portion 140a. Or (3) that the end 140a is embedded in a part of the light shield 130. In this embodiment, the upper end 130a is connected to the end 140a.

Further, the lower end portion 130b, which is the end portion of the light shielding portion 130 on the light emitting portion 120 side, is on the straight line L. Therefore, the angle formed by the light shielding portion 130 and the perpendicular P coincides with the angle formed by the straight line L and the perpendicular P (light receiving angle φ of the light projecting lens 140).

The outer shape of the light shielding portion 130 is an inverted truncated cone or a substantially inverted truncated cone, and the lower end portion 130b has a light inlet 130c. The light blocking unit 130 takes in the light emitted by the light emitting unit 120 from the light receiving port 130c and guides it to the light projecting lens 140.

The incident angle θ of the laser light R from the laser element 110 to the light emitting section 120 is more preferably the same as the light taking-in angle φ of the light projecting lens 140 or larger than the light taking-in angle φ. In other words, it is desirable that each part of the illuminating device 100 be configured such that the light capturing angle φ is equal to or smaller than the incident angle θ.

At least the outer surface 130d of the light blocking portion 130 blocks light. It is desirable that the light shielding portion 130 is made of a material having a high absorption rate for the wavelength of the laser light R and a high laser damage threshold value. The inner side surface of the light shielding unit 130 is not limited to the above, and may have reflectivity, for example.

(effect)
The effects of the lighting device 100 will be described with reference to FIGS. 2 to 4. FIG. 2 is a diagram illustrating an example of effects of the lighting device 100. FIG. 3 is a diagram illustrating another example of the effect of the lighting device 100. FIG. 4A and FIG. 4B are diagrams illustrating reduction of color unevenness by the lighting device 100.

As shown in FIG. 2, by providing the light shielding unit 130 between the light projecting lens 140 and the light emitting unit 120, it is possible to reduce stray light taken into the light projecting lens 140. In other words, by installing the light shielding unit 130, it is possible to exclude stray light M other than the light that is captured inside the light shielding unit 130 from the light inlet 130c.

Specifically, the end portion 140a of the light projecting lens 140 is connected to the upper end portion 130a of the cylindrical light shielding portion 130, and the lower end portion 130b of the light shielding portion 130 is on the straight line L. In other words, the area from the light inlet 130c to the end 140a of the light projecting lens 140 is covered with the light shield 130 that shields light. As a result, the light other than the light taken in through the light receiving port 130c is blocked by the outer side surface of the light blocking section 130 and does not enter the light blocking section 130. Therefore, the stray light M included in the light projected from the light projecting lens 140 can be reduced, so that the color unevenness of the light projected from the light projecting lens 140 can be prevented.

Further, as shown in FIG. 3, by setting the light taking-in angle φ to be equal to or smaller than the incident angle θ of the laser element 110, among the laser light R reflected by the light emitting section 120, the light that is regularly reflected by the light emitting section 120 is strong. Can be prevented from being taken into the inside of the light shielding portion 130 from the light taking-in port 130c. In other words, the laser light R specularly reflected by the light emitting unit 120 from the laser element 110 is not captured by the light projecting lens 140.

Specifically, the laser light R is specularly reflected by the light emitting section 120 at the same angle θ as the incident angle θ. Therefore, by setting the light taking-in angle φ to be equal to or smaller than the incident angle θ of the laser element 110, the specularly reflected laser light R advances in a direction beyond the light taking-in port 130c, so that the specularly reflected laser light R is shielded. Is not taken inside. Therefore, since the laser light R having a high light intensity from the laser element 110 that is specularly reflected by the light emitting unit 120 is not included in the light projected from the light projecting lens 140, the color of the light projected from the light projecting lens 140. The unevenness can be prevented.

In addition, in the light source device described in Patent Document 1, when the incident angle of light from the fixed light source to the phosphor portion changes due to impact or the like, the light from the fixed light source may be directly projected to the outside. There was a problem that there is. However, since the light-shielding portion 130 according to the present embodiment does not take in light from other than the light inlet 130c, even if the direction of the laser light R is changed due to a shock or the like, the direction of the illumination device 100 is changed. It is possible to prevent the laser light R having the changed value from being directly taken inside the light shielding unit 130. Therefore, it is possible to prevent color unevenness of the light projected from the light projecting lens 140 when the direction of the laser light R changes due to an impact or the like.

FIG. 4A is a light distribution photograph on the screen when light is projected on the screen by a conventional lighting device. FIG. 4B is a light distribution photograph on the screen when the illumination device 100 according to the present embodiment projects light on the screen. As shown in FIGS. 4A and 4B, according to the lighting device 100, the blue component light 200 seen in the light distribution diagram of the conventional lighting device can be removed, and the light projecting lens 140 can be removed. It can be seen that the uneven color of the light emitted from is improved.

[Modification of the light shielding part]
The light emitted from the light emitting unit 120 ideally enters the light projecting lens 140 from the center C of the light emitting unit 120. However, the actual light emission is not limited to one point of the center C but is equal to the size of the beam spot. Emitted from the area of. Therefore, there is a small amount of light that reaches the inner surface of the light shield 130 from the light emitting unit 120. Further, the light that reaches the inner side surface of the light shield 130 and is reflected may be captured by the light projecting lens 140 and projected.

In view of this, by deforming the inner surface of the light shielding unit 130 in particular, the light projection distribution pattern of the light projected from the light projection lens 140 is controlled.

A modified example of the light shielding unit 130 according to the first embodiment of the present invention will be described with reference to FIGS. 5A to 5D.

FIG. 5A shows the basic shape of the light shielding unit 130.

The light blocking portion 131 shown in FIG. 5B is a modification of the light blocking portion 130, and the light blocking portion 131 has a curved surface 131e that is convex outward. If the inner side surface of the light blocking portion 131 is made of a highly reflective material, the light that reaches the inner side surface of the light blocking portion 131 is reflected by the inner side surface and is incident on the light projecting lens 140, so that the light projecting lens 140 projects light. It is possible to distribute light in a narrower range. Even if the inner side surface of the light shielding portion 131 is made of a highly absorbent material, most of the light reaching the inner side surface of the light shielding portion 131 is absorbed, but a highly reflective material is used as the inner side surface of the light shielding portion 131. As in the case, it is possible to perform light distribution with a narrowed range of light projection.

The light-shielding portion 132 shown in FIG. 5C is another modification of the light-shielding portion 130, and the light-shielding portion 132 extends from the upper end portion 132a on the light projecting lens 140 side in a direction parallel to the perpendicular P. It has a shaped portion 132e and a bottom portion 132f that is provided with a conical tapered portion 132g that extends in the direction of the perpendicular P and tapers toward the light emitting portion 120 side. When the inner surface of the light blocking portion 132 is made of a highly absorbent member, most of the light reaching the inner surface of the light blocking portion 132 is absorbed, and the light that is not absorbed and reflected is less likely to enter the light projecting lens 140. ..

The light shielding portion 133 shown in FIG. 5D is still another modification of the light shielding portion 130, and the light shielding portion 133 has a curved surface 133e that is convex inward. When the inner side surface of the light shielding portion 133 is made of a highly absorbent material, a large amount of light reaching the inner side surface of the light shielding portion 133 is cut by the portion that is convex inside the light shielding portion 133, and a sharper projection pattern is possible. Become.

5B, FIG. 5C, and FIG. 5D, the light-shielding portions 131, 132, 133 have their end portions on the side of the light projecting lens 140 (upper end portions 131a, 132a, 133a). Is connected to the end portion 140a of the light projecting lens 140, and the end portions (lower end portions 131b, 132b, 133b) of the light shielding portions 131, 132, 133 on the light emitting portion 120 side are the end portion 140a of the light projecting lens 140 and the light emitting portion 120. It is on a straight line L connecting the center C of.

By deforming the light shielding portion 130 as described above, the light projection distribution pattern can be arbitrarily controlled by changing the inner surface reflection component.

[Embodiment 2]
Embodiment 2 of the present invention will be described with reference to FIG. FIG. 6 is a schematic diagram showing a schematic configuration of a lighting device 100A according to the second embodiment of the present invention. The illumination device 100A shown in FIG. 7 is different from the illumination device 100 shown in FIG. 1 in that a light emitting unit 120A, a reflection mirror 150, and a light shielding unit 134 are provided instead of the light emitting unit 120 and the light shielding unit 130. However, other configurations are the same.

The light emitting unit 120A receives the laser light R emitted from the laser element 110, emits fluorescence and emits light. The light emitting section 120A includes a phosphor section 121 and a reflective substrate 122.

The phosphor section 121 has the same configuration as the light emitting section 120. As the phosphor of the phosphor unit 121, for example, an oxynitride-based phosphor (for example, sialon phosphor) or a III-V group compound semiconductor nanoparticle phosphor (for example, indium phosphide:InP) can be used. These phosphors have high heat resistance to the high-power (and/or light-density) laser light R emitted from the laser element 110, and are suitable for a laser illumination light source. However, the phosphor of the phosphor unit 121 is not limited to the above-mentioned one, and may be another phosphor such as a nitride phosphor. The phosphor portion 121 is laminated on the light projecting lens 140 side of the reflective substrate 122.

The reflection system substrate 122 reflects the light emitted by the phosphor section 121 and the laser light R to the front surface of the reflection system substrate 122 (on the light projecting lens 140 side).

The reflection mirror 150 reflects the laser light emitted from the laser element 110 and guides it to the light emitting unit 120A. The reflection mirror 150 can be a simple convex mirror or a concave mirror. By using the reflection mirror 150, only by changing the direction (angle) of the reflection mirror 150 without changing the direction of the laser element 110, the incident angle θ1 of the laser light R to the light emitting section 120A and the like can be made more accurate. It can be changed easily. A plurality of reflection mirrors 150 may be provided.

The light blocking section 134 has substantially the same configuration as the light blocking section 130. Specifically, the light blocking section 134 is provided between the light emitting section 120A and the light projecting lens 140, and has a cylindrical shape that blocks light on the outer surface 134d. An end portion (upper end portion 134a) of the light shielding portion 134 on the light projecting lens 140 side is connected to an end portion 140a of the light projecting lens 140. An end portion (lower end portion 134b) of the light shielding portion 134 on the light emitting portion 120A side is on a straight line L1 connecting the end portion 140a of the light projecting lens 140 and the center C1 of the light emitting portion 120A.

Further, the angle formed by the perpendicular line P1 of the light emitting portion 120A passing through the center C1 of the light emitting portion 120A and the straight line L1 (light receiving angle φ1) is not more than the incident angle θ1 of the laser light R to the light emitting portion 120A. In other words, it is more preferable that the incident angle θ1 of the laser element 110 to the light emitting section 120A is the same as the light taking-in angle φ1 or larger than the light taking-in angle φ1.

According to the lighting device 100A, it is possible to prevent stray light and excitation light components (for example, the component of the laser light R specularly reflected by the light emitting unit 120A) from being projected to the outside of the lighting device 100A through the light projecting lens 140. You can Further, when the direction of the laser light R is changed due to a shock or the like, it is possible to prevent the laser light R from being directly projected to the outside of the illumination device 100A via the light projecting lens 140.

[Embodiment 3]
The third embodiment of the present invention will be described with reference to FIG. FIG. 7: is a schematic diagram which shows schematic structure of the illuminating device 100B which concerns on Embodiment 3 of this invention. The illumination device 100B shown in FIG. 7 is different from the illumination device 100 shown in FIG. 1 in that a light emitting unit 120B and a light shielding unit 135 are provided instead of the light emitting unit 120 and the light shielding unit 130, and the others. The configuration is the same.

The light emitting section 120B receives the laser light R emitted from the laser element 110, emits fluorescence and emits light. The light emitting unit 120B is different from the light emitting unit 120A shown in FIG. 6 in that a transmissive substrate 123 is provided instead of the reflective substrate 122, and the other configurations are the same. Further, in the present embodiment, the laser light R emitted from the laser element 110 is incident on the light emitting unit 120B from the side opposite to the side on which the light projecting lens 140 is installed. In other words, the light emitting unit 120B emits fluorescence from one surface, and the laser light R is incident on the light emitting unit 120B from the surface opposite to the surface emitting the fluorescence.

The transmissive substrate 123 transmits the laser light R emitted from the laser element 110, and reflects the light emitted by the phosphor portion 121 to the front surface of the transmissive substrate 123 (on the light projecting lens 140 side). The phosphor portion 121 is stacked on the transmission substrate 123 on the light projecting lens 140 side.

The light blocking portion 135 has substantially the same configuration as the light blocking portion 130. Specifically, the light blocking portion 135 is provided between the light emitting portion 120B and the light projecting lens 140, and has a cylindrical shape that blocks light on the outer surface 135d. An end portion (upper end portion 135a) of the light blocking portion 135 on the light projecting lens 140 side is connected to an end portion 140a of the light projecting lens 140. An end portion (lower end portion 135b) of the light shielding portion 135 on the light emitting portion 120B side is on a straight line L2 connecting the end portion 140a of the light projecting lens 140 and the center C2 of the light emitting portion 120B.

Further, the angle formed by the perpendicular line P2 of the light emitting portion 120B passing through the center C2 of the light emitting portion 120B and the straight line L2 (light receiving angle φ2) is not more than the incident angle θ2 of the laser light R on the light emitting portion 120B. In other words, it is more preferable that the incident angle θ2 of the laser element 110 on the light emitting portion 120B is the same as the light taking-in angle φ2 or larger than the light taking-in angle φ2.

(effect)
Effects of the lighting device 100B will be described with reference to FIG. FIG. 8: is a figure explaining an example of the effect of the illuminating device 100B. As shown in FIG. 8, by setting the light taking-in angle φ2 to be equal to or smaller than the incident angle θ2 of the laser element 110, the laser light R having a high light intensity transmitted through the light emitting section 120B is emitted from the light taking-in port 135c to the light blocking section 135. It can be left unloaded inside.

Specifically, in the light emitting section 120B, the laser light R from the laser element 110 passes through the light emitting section 120B at an incident angle θ. Therefore, by setting the light taking-in angle φ2 to be equal to or smaller than the incident angle θ2 of the laser element 110, the transmitted laser light R advances in a direction exceeding the light taking-in port 135c, and thus the transmitted laser light R is inside the light shielding portion 135. Not taken into. Therefore, the laser light R having a high light intensity from the laser element 110 that has passed through the light emitting unit 120B is not included in the light projected from the light projecting lens 140, and thus the color of the light projected from the light projecting lens 140. The unevenness can be prevented.

[Embodiment 4]
An illumination device 100C according to Embodiment 4 of the present invention will be described with reference to FIG. FIG. 9: is a figure which shows schematic structure of the illuminating device 100C which concerns on Embodiment 4 of this invention. The illuminating device 100C shown in FIG. 9 is different from the illuminating device 100A shown in FIG. 6 in that a light shielding part 136, a cover 160, and a light projecting lens fixing part 161 are provided instead of the light shielding part 134. Other configurations are the same. The laser element 110 is not shown in FIG.

The cover 160 covers the light blocking portion 136. The cover 160 is a member having a substantially inverted conical shape, and has a bottom surface 160a and a side surface 160b. The bottom surface 160a has a circular shape, and the light emitting unit 120A is installed in the center thereof. The side surface 160b has a tapered shape that spreads from the bottom surface 160a toward the light projecting lens 140 side. The light shield 136 is provided in the recess of the cover 160. Further, the cover 160 covers the end portion 140 a of the light projecting lens 140. The cover 160 covers the end portion 140a means, for example, (1) that the outer diameter of the upper end portion 160c which is the end portion of the cover 160 on the light projecting lens 140 side is equal to or larger than the outer diameter of the end portion 140a, (2) This means that the upper end portion 160c is connected to the end portion 140a, or (3) the end portion 140a is included in a part of the cover 160. In this embodiment, the upper end 160c is connected to the end 140a.

The light projection lens fixing portion 161 fixes the light projection lens 140. Specifically, the outer peripheral side of the light projecting lens 140 is fixed from the end portion 141a of the effective light projecting range 141 of the light projecting lens 140. In other words, the projection lens 140 outside the range fixed by the projection lens fixing portion 161 becomes the effective projection range 141. The effective light projecting range 141 is a range in which the light projecting lens 140 can actually project light.

The light shield 136 has substantially the same configuration as the light shield 130. Specifically, the light blocking section 136 is provided between the light emitting section 120A and the light projecting lens 140, and has a cylindrical shape that blocks light on the outer side surface 136d. The lower end 136b of the light shielding unit 136 on the light emitting unit 120A side is located on the straight line L3 that connects the end 141a of the effective light emitting range 141, which is the range in which light can be emitted by the light projecting lens 140, and the center C2 of the light emitting unit 120A. is there. An end portion (upper end portion 136a) of the light blocking portion 136 on the light projecting lens 140 side is in contact with the inner peripheral surface 160d of the cover 160.

Further, the angle formed by the perpendicular line P2 of the light emitting portion passing through the center C2 of the light emitting portion 120A and the straight line L3 (light receiving angle φ3) is equal to or smaller than the incident angle θ3 of the laser light R on the light emitting portion 120A.

According to the lighting device 100C, the end 140a is covered with the light shield 136 and the cover 160. The upper end 136a is in contact with the inner peripheral surface 160d of the cover 160. As a result, the light other than the light taken in from the lower end 136b does not enter the inside of the light shield 136. Therefore, stray light included in the light projected from the light projecting lens 140 can be reduced, and thus it is possible to prevent color unevenness of the projected light.

Further, the lower end portion 136b is on the straight line L3, and the light receiving angle φ3 is equal to or smaller than the incident angle θ3. As a result, the laser light R specularly reflected by the light emitting section 120A is not taken inside the light shielding section 136. Therefore, since the laser light R having a high light intensity from the laser element 110 that is specularly reflected by the light emitting unit 120A is not included in the light projected from the light projecting lens 140, uneven color of the projected light can be prevented. it can.

In each of the embodiments, the light projecting lens 140 is described as being circular, but the shape of the light projecting lens 140 is not limited to being circular as long as the light receiving angle φ is smaller than the incident angle θ. The light projecting lens 140 may be an ellipse or a quadrangle.

[Summary]
An illumination device (100/100A/100B/100C) according to aspect 1 of the present invention receives an excitation light source (laser element 110) that emits excitation light (laser light R) and an excitation light emitted from the excitation light source. Provided between the light emitting unit and the light emitting unit, and a light emitting unit (120, 120A, 120B) that emits fluorescent light, a light projecting unit (140) that projects the light emitted from the light emitting unit. And a light-shielding portion (130, 131, 132, 133, 134, 135, 136), which connects the end portion of the light projecting portion and the center (C, C1, C2) of the light emitting portion (L). .L1.L2.L3) and the normal line (P.P1.P2) of the light emitting part passing through the center of the light emitting part (light receiving angle .phi..phi.1 .phi.2 .phi.3) is the excitation light. Is less than or equal to the angle of incidence (θ·θ1·θ2·θ3) on the light emitting portion.

According to the above configuration, the light shielding unit is provided between the light projecting unit and the light emitting unit. As a result, stray light captured by the light projecting unit can be reduced, and thus uneven color of the projected light can be prevented.

Further, an angle formed by the straight line and a perpendicular line of the light emitting portion passing through the center of the light emitting portion is equal to or smaller than an incident angle of the excitation light to the light emitting portion. Thereby, the excitation light from the excitation light source that is specularly reflected by the light emitting unit is not taken into the light projecting unit. Therefore, since the excitation light having a high light intensity from the excitation light source that is specularly reflected in the light emitting portion is not included in the light emitted from the light emitting portion, it is possible to prevent color unevenness of the emitted light.

The illumination device 100A according to Aspect 2 of the present invention is the reflection mirror according to Aspect 1, wherein the excitation light (laser light R) emitted from the excitation light source (laser element 110) is reflected and guided to the light emitting unit (120A). It is preferable to have 150.

According to the above configuration, a reflection type illumination device can be used.

The illumination device 100B according to Aspect 3 of the present invention is the illumination device 100B according to Aspect 1, wherein the light emitting section (120B) emits fluorescence from one surface and excitation light (laser light) from the surface opposite to the surface emitting the fluorescence. R) is preferably incident on the light emitting unit.

According to the above configuration, a transmissive illumination device can be used.

The illumination device (100) according to aspect 4 of the present invention is the illumination device (100) according to any one of aspects 1 to 3, wherein the light-shielding portion (light-shielding portion 131) has a curved surface (131e) that is convex outward. preferable.

According to the above configuration, it is possible to arbitrarily control the projected light distribution pattern.

The illumination device 100 according to Aspect 5 of the present invention is the illumination device 100 according to any one of Aspects 1 to 3, wherein the light-shielding portion (light-shielding portion 132) is the end portion (upper end portion 132a) on the light-projecting portion (140) side. It is preferable to have a cylindrical portion (132e) extending in a direction parallel to the perpendicular (P) and a conical tapered portion (132g) that is tapered toward the light emitting portion (120) side.

According to the above configuration, it is possible to arbitrarily control the projected light distribution pattern.

The illumination device 100 according to aspect 6 of the present invention is the illumination device 100 according to any one of aspects 1 to 3, wherein the light-shielding portion (light-shielding portion 133) has a curved surface (133e) that is convex toward the inside.

According to the above configuration, it is possible to arbitrarily control the projected light distribution pattern.

An illumination device 100C according to Aspect 7 of the present invention is the illumination device 100C according to any one of Aspects 1 to 6, further including a cover (160) that covers the light shielding portion (light shielding portion 136), and the cover includes the light projecting portion. A straight line (L3) that covers the end portion (140a) of (140) and connects the end portion (141a) of the effective light emitting range (141), which is the range in which light can be emitted by the light emitting unit, and the center of the light emitting unit. ) Above, there is an end portion (lower end portion 136b) on the light emitting portion side of the light shielding portion (light shielding portion 136), and the perpendicular line (P3), the end portion of the effective light emitting range, and the center of the light emitting portion. The angle (φ3) formed by the connecting straight line (L3) is equal to or smaller than the incident angle (θ3) of the excitation light (laser light R) to the light emitting section (120), and the angle of the light blocking section (light blocking section 136) is the same. The end portion (upper end portion 136a) on the light projecting portion side is in contact with the inner peripheral surface (160d) of the cover.

According to the above configuration, the end portion of the light projecting portion is covered with the light shielding portion and the cover. Further, the end portion of the light shielding portion on the light emitting portion side is in contact with the inner peripheral surface of the cover. As a result, the light other than the light taken in from the end on the light emitting portion side of the light shield does not enter the inside of the light shield. Therefore, it is possible to reduce stray light captured inside the light-shielding portion, so that it is possible to prevent color unevenness of the projected light.

Further, the end of the light shield on the light emitting side is on a straight line connecting the end of the effective light emitting range, which is the range where the fluorescent light is projected in the light projecting part, and the center of the light emitting part. The angle formed by the vertical line of the light emitting portion passing through the center of is equal to or smaller than the incident angle of the excitation light to the light emitting portion. As a result, the excitation light from the excitation light source that is specularly reflected by the light emitting unit is not captured inside the light shielding unit. Therefore, since the excitation light having a high light intensity from the excitation light source that is specularly reflected in the light emitting portion is not included in the light emitted from the light emitting portion, it is possible to prevent color unevenness of the emitted light.

It is preferable that the vehicle headlamp according to the eighth aspect of the present invention includes the illumination device (100/100A/100B/100C) described in any one of the first to seventh aspects.

According to the above configuration, the same effect as that of the first aspect is achieved.

An illumination device (100/100A/100B/100C) according to aspect 9 of the present invention receives an excitation light source (laser element 110) that emits excitation light (laser light R) and an excitation light emitted from the excitation light source. Of the light emitting section (120/120A/120B) that emits fluorescence and emits light, a light projecting section (140) that projects the light emitted from the light emitting section, and the light emitting section and the light projecting section. And a cylindrical light-shielding portion (130, 131, 132, 133, 134, 135, 136) provided between the light-shielding portion and the outer surface thereof, the light-shielding portion being an end portion 140a of the light-projecting portion. And an end portion (lower end portion 130b, 131b, 132b, 133b, 133b, 135b, 136b) of the light shielding portion on the side of the light emitting portion is located at the end of the light emitting portion and the center of the light emitting portion (C, C1,. C2) is on a straight line (L·L1, L2, L3) that connects with the perpendicular line (P·P1·P2) of the light emitting portion that passes through the center of the light emitting portion and the straight line (light receiving angle). It is preferable that φ·φ1·φ2·φ3) is equal to or less than the incident angle (θ·θ1·θ2·θ3) of the excitation light to the light emitting portion.

According to the above configuration, the end portion of the light projecting portion is covered with the cylindrical light shielding portion that shields light on the outer side surface. As a result, the light other than the light taken in from the end on the light emitting portion side of the light shield does not enter the inside of the light shield. Therefore, it is possible to reduce stray light captured inside the light-shielding portion, so that it is possible to prevent color unevenness of the projected light.

Further, the end of the light shield on the light emitting side is on a straight line connecting the end of the light emitting part and the center of the light emitting part, and the angle formed by the straight line and the perpendicular of the light emitting part passing through the center of the light emitting part is It is not more than the angle of incidence of the excitation light on the light emitting portion. As a result, the excitation light from the excitation light source that is specularly reflected by the light emitting unit is not captured inside the light shielding unit. Therefore, since the excitation light having a high light intensity from the excitation light source that is specularly reflected in the light emitting portion is not included in the light emitted from the light emitting portion, it is possible to prevent color unevenness of the emitted light.

The present invention is not limited to the above-described embodiments, but various modifications can be made within the scope of the claims, and embodiments obtained by appropriately combining the technical means disclosed in the different embodiments Is also included in the technical scope of the present invention. Furthermore, a new technical feature can be formed by combining the technical means disclosed in each embodiment.

100/100A/100B/100C Illumination device 110 Laser element (excitation light source)
120/120A/120B Light emitting part 130/131/132/133/134/135/136 Light shielding part 130a/131a/132a/133a/134a/135a/136a Upper end part (end part of light shielding part on light projecting part side)
130b/131b/132b/133b/134b/135b/136b Lower end part (end part on light emitting part side of light shielding part)
131e/133e Curved surface 132e Cylindrical part 132g Conical tapered part 140 Projection lens (projection part)
140a end (end of light emitting part)
141 Effective light emitting range 141a End (end of effective light emitting range)
150 Reflecting mirror 160 Cover 160d Inner surface (inner surface of cover)
C・C1・C2 Center L・L1・L2・L3 Straight line P・P1・P2 Perpendicular R Laser light (excitation light)
θ・θ1・θ2・θ3 Incident angle φ・φ1・φ2・φ3 Light capture angle (angle between perpendicular and straight line)

Claims (5)

An excitation light source that emits excitation light,
A light emitting unit that emits fluorescence by receiving excitation light emitted from the excitation light source,
A light projecting unit for projecting light emitted from the light emitting unit;
A light shielding unit provided between the light emitting unit and the light projecting unit,
The light-shielding portion is a tubular hollow member that covers an end portion of the light projecting portion,
The end of the light shield on the side of the light emitting unit is on a straight line connecting the end of the light emitting unit and the center of the light emitting unit,
An angle formed by a straight line connecting the end portion of the light projecting portion and the center of the light emitting portion and a perpendicular line of the light emitting portion passing through the center of the light emitting portion is equal to or less than an incident angle of the excitation light to the light emitting portion. A lighting device characterized by being present. The illumination device according to claim 1, further comprising a reflection mirror that reflects the excitation light emitted from the excitation light source and guides the excitation light to the light emitting unit. The lighting device according to claim 1, wherein the light emitting unit emits fluorescence from one surface, and the excitation light is incident on the light emitting unit from a surface opposite to the surface emitting the fluorescence. With a cover for covering the light shielding part,
The cover covers an end portion of the light projecting portion,
On the straight line connecting the end of the effective light emitting range, which is the range in which light can be emitted in the light emitting unit, and the center of the light emitting unit, there is the end of the light shielding unit on the light emitting unit side,
The angle formed by the perpendicular and the straight line connecting the end of the effective light projection range and the center of the light emitting unit is equal to or less than the incident angle of the excitation light to the light emitting unit,
The lighting device according to any one of claims 1 to 3, wherein an end portion of the light blocking portion on the light projecting portion side is in contact with an inner peripheral surface of the cover. A vehicle headlamp comprising the lighting device according to any one of claims 1 to 4.