CN111089231A

CN111089231A - Light source device

Info

Publication number: CN111089231A
Application number: CN201811233571.4A
Authority: CN
Inventors: 陈彬; 张贤鹏; 李屹
Original assignee: Appotronics Corp Ltd
Current assignee: Shenzhen Appotronics Corp Ltd
Priority date: 2018-10-23
Filing date: 2018-10-23
Publication date: 2020-05-01
Anticipated expiration: 2038-10-23
Also published as: WO2020082974A1; CN111089231B

Abstract

The invention protects a light source device, comprising a laser light source, a first light source, a second light source and a control unit, wherein the laser light source is used for emitting first light; the wavelength conversion device is arranged on a light path of the first light, and comprises a transparent wavelength conversion layer and a transparent light guide layer which are sequentially arranged along the incident direction of the first light, wherein the transparent wavelength conversion layer comprises a first surface which is a light incident surface and a light emergent surface of the wavelength conversion device; the wavelength conversion device also comprises a light reflection structure which is arranged on the surface of the transparent light guide layer far away from the transparent wavelength conversion layer; the transparent wavelength conversion layer absorbs part of the first light and emits second light with a wavelength range different from that of the first light, and part of the first light enters the transparent light guide layer through the transparent wavelength conversion layer. Compared with the prior art, the invention leads the unabsorbed first light to be conducted by the transparent light guide layer twice, increases the optical path, enlarges the beam sectional area, and leads the facula of the first light emitted by the wavelength conversion device to be enlarged to be matched with the facula of the second light, thereby improving the color uniformity of the emergent light of the light source device.

Description

Light source device

Technical Field

The invention relates to the technical field of illumination, in particular to a light source device.

Background

The existing illumination light sources mainly comprise LED, xenon lamp and halogen lamp light sources, and the LED, xenon lamp and halogen lamp light sources respectively have the defects of short illumination distance caused by insufficient brightness, short service life, large beam divergence angle and the like. As a new illumination technology, laser illumination is a development trend of future illumination due to characteristics of high brightness, long service life, small collimation and divergence angle of laser beams, and the like.

In order to obtain white light for illumination and display, a red-green-blue laser or a laser excited wavelength conversion material (such as fluorescent powder) is used. The white light obtained by the red, green and blue lasers has a large color gamut range, high brightness and high cost, and is suitable for being applied to the high-end display field. For the illumination field, the red, green and blue laser covers a narrow wavelength range and a low display index, and is not practical. The white light obtained by laser excitation of the wavelength conversion material also has high brightness, and is more economical than the red, green and blue laser, thus being better.

However, when a yellow fluorescent material is actually excited by using a blue laser, there often occurs a case where the color of the emitted light is not uniform, specifically, it appears that the center is bluish and the edge is yellowish.

Fig. 8a shows a light source device for laser excitation of a wavelength conversion material, which includes a laser light source 1 and a wavelength conversion layer 2, wherein the wavelength conversion layer 2 is disposed in a groove 3 of a reflection wall surface. The laser light source 1 emits blue laser light (indicated by a solid line B in the figure), the wavelength conversion layer 2 contains a yellow fluorescent material, the blue laser light is normally incident on the wavelength conversion layer 2 and is partially absorbed, and then the wavelength conversion layer 2 emits yellow light (indicated by a broken line Y in the figure), and the yellow light and unabsorbed blue light are emitted from the incident surface of the wavelength conversion layer 2. In the technical scheme, the wavelength conversion layer 2 is an opaque layer, blue light entering the wavelength conversion layer 2 is basically absorbed, and the residual blue light emitted by the light source device mainly comes from a position close to an incident surface of the wavelength conversion layer 2, so that the spot size of the residual blue light is basically equal to that of the incident laser. The yellow light comes from light emitted from each position when the blue light propagates in the wavelength conversion layer, and part of light beams are emitted after being reflected for multiple times in the wavelength conversion layer, so that the light spot of the yellow light is obviously enlarged relative to the light spot of the blue light, the edge of the total emergent light spot is yellowish, and the color distribution is not uniform.

Fig. 8b shows another embodiment of a light source device for laser excitation of a wavelength conversion material, which includes a laser light source 1 ', a wavelength conversion layer 2', and a groove 3 'for accommodating the wavelength conversion layer 2'. Unlike the solution shown in fig. a, the wavelength conversion layer 2 ' of the present solution is a transparent layer, and the unabsorbed blue light passes through the wavelength conversion layer 2 ' to reach the bottom of the groove 3 ' and then is reflected out. A transparent wavelength converting layer can convert 90% of the laser light into fluorescent light over a short distance (e.g. less than 0.2mm thickness for 2% Ce-concentrated YAG), so that the remaining blue light cannot diffuse to the entire entrance face of the wavelength converting layer 2' during reflection back to the entrance face; the yellow light is emitted in all angles of 360 degrees at each position where the blue light is absorbed, and can fill the whole incident surface of the wavelength conversion layer 2 'through the reflection of the bottom and the side wall of the groove 3'. Therefore, under the technical scheme, the blue light spot of the emergent light is still smaller than the yellow light spot, so that the color distribution of the emergent light is not uniform.

Disclosure of Invention

Aiming at the defect of uneven emergent light color of the light source device of the laser excitation wavelength conversion material in the prior art, the invention provides the light source device with the even emergent light color, which comprises a laser light source and a light source module, wherein the laser light source is used for emitting first light; the wavelength conversion device is arranged on a light path of the first light, and comprises a transparent wavelength conversion layer and a transparent light guide layer which are sequentially arranged along the incident direction of the first light, wherein the transparent wavelength conversion layer comprises a first surface which is a light incident surface and a light emergent surface of the wavelength conversion device; the wavelength conversion device also comprises a light reflection structure which is arranged on the surface of the transparent light guide layer far away from the transparent wavelength conversion layer; the transparent wavelength conversion layer absorbs part of the first light and emits second light with a wavelength range different from that of the first light, part of the first light enters the transparent light guide layer through the transparent wavelength conversion layer, and emergent light of the wavelength conversion device is mixed light of the first light and the second light.

Compared with the prior art, the invention has the following beneficial effects: through set gradually transparent wavelength conversion layer and transparent leaded light layer on the incident direction at first light, and set up the light reflection structure on the surface of the transparent leaded light layer of keeping away from transparent wavelength conversion layer, make the first light that is not absorbed by transparent wavelength conversion layer enter into transparent leaded light layer, and the back is reflected back transparent wavelength conversion layer by the light reflection structure, this process makes the first light of unabsorbed twice through the conduction on transparent leaded light layer, the optical path has been increased, the beam cross-sectional area has been enlarged, finally make the facula of the first light of wavelength conversion equipment outgoing enlarge, with the facula phase-match of second light, thereby the emergent light colour homogeneity of light source device has been improved.

In one embodiment, the transparent wavelength converting layer is a fluorescent single crystal or a transparent fluorescent ceramic.

In one embodiment, the transparent wavelength converting layer is a Ce: YAG fluorescent single crystal.

In one embodiment, the transparent light guide layer is a light guide medium layer with a refractive index greater than 1.

In one embodiment, the transparent light guiding layer is a sapphire layer.

In one embodiment, an air space is provided between the transparent wavelength conversion layer and the transparent light guide layer. In this embodiment, the light reaching the surface of the transparent wavelength conversion layer opposite to the first surface includes the first light that is not absorbed and the second light that is emitted by the transparent wavelength conversion layer. Wherein the first light is unscattered, typically light with a small divergence angle and a small incident angle; and the second light is 360 ° emitted light, including light incident angles from 0 ° to 90 °. Through setting up the air interval, can make first light direct transmission, and some second light is reflected back transparent wavelength conversion layer by the total reflection at this interface position to reduced the second light and propagated and the light loss that is brought by the reflection in transparent leaded light layer, improved the light utilization ratio of second light.

In one embodiment, the transparent wavelength conversion layer and the transparent light guide layer are integrally molded, or the transparent wavelength conversion layer and the transparent light guide layer are connected through a glue layer.

In one embodiment, the transparent light guiding layer further comprises scattering particles. According to the technical scheme, the first light incident to the transparent light guide layer can be expanded by the scattered light beam, and the light spot of the first light can be expanded within a shorter distance.

In one embodiment, the transparent light guide layer is an air layer.

In one embodiment, the thickness of the transparent light guiding layer is not less than 3 times the thickness of the transparent wavelength conversion layer.

In one embodiment, the light reflection structure is a reflection groove, and the transparent wavelength conversion layer and the transparent light guide layer are disposed in the reflection groove.

In another embodiment, the light reflecting structure is a reflective coating. In particular, the reflective coating may be a metallic reflective layer, such as silver or aluminum, or a dielectric reflective layer composed of a plurality of layer structures having different refractive indices.

In one embodiment, the light reflecting structure is at least partially a diffuse reflecting structure. Specifically, the diffuse reflection structure may be a layer structure including diffuse reflection particles and glass frit, or may be a rough structure on the surface of the transparent light guide layer.

In one embodiment, the first light is polarized and is obliquely incident to the first face at brewster's angle.

In one embodiment, the light source device further comprises a light guiding device disposed between the laser light source and the wavelength conversion device for guiding the first light to the first surface. Specifically, the light guiding device may be a reflector with a hole, the first light is incident to the first surface through a small hole of the reflector, and the combined light of the first light and the second light emitted from the wavelength conversion device is reflected by the reflector and then emitted.

In one embodiment, the wavelength conversion device further includes a heat sink disposed outside the light reflection structure, and the light reflection structure and the heat sink are connected by a heat conductive adhesive.

Drawings

Fig. 1 is a schematic structural diagram of a light source device according to a first embodiment of the invention.

Fig. 2 is a schematic structural diagram of a light source device according to a second embodiment of the invention.

Fig. 3 is a schematic structural diagram of a light source device according to a third embodiment of the present invention.

Fig. 4 is a schematic structural diagram of a light source device according to a fourth embodiment of the present invention.

Fig. 5 is a schematic structural diagram of a light source device according to a fifth embodiment of the present invention.

Fig. 6 is a schematic structural diagram of a light source device according to a sixth embodiment of the present invention.

FIG. 7 shows a wavelength conversion device without a transparent light guide layer and a wavelength conversion device with a transparent light guide layer

And (4) arranging the emergent light spot color distribution diagram.

Fig. 8a is a schematic diagram of a light source device for laser excitation of a wavelength conversion material.

Fig. 8b is another embodiment of a light source device for laser excitation of a wavelength conversion material.

Detailed Description

The embodiments of the present invention will be described in detail below with reference to the drawings and the embodiments.

Descriptions related to "first", "second", "third", etc. in the present invention are for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first," "second," or "third" may explicitly or implicitly include at least one of the feature.

Fig. 1 is a schematic structural diagram of a light source device according to a first embodiment of the invention. The light source device 10 includes a laser light source 110 and a wavelength conversion device 120. The laser light source 110 emits the first light L1. The wavelength conversion device 120 is disposed on an optical path of the first light L1 (indicated by a solid arrow in the figure) emitted from the laser light source 110, and includes a transparent wavelength conversion layer 121 and a transparent light guide layer 122 disposed in this order along the first light incident direction. The transparent wavelength conversion layer 121 includes a first surface (not shown) which is a light incident surface and a light emitting surface of the wavelength conversion device 120.

The wavelength conversion device 120 further includes a light reflection structure 123 disposed on a surface of the transparent light guide layer 122 away from the transparent wavelength conversion layer 121.

The transparent wavelength conversion layer 121 absorbs a portion of the first light and emits a second light L2 (indicated by a dotted arrow in the figure) with a wavelength range different from that of the first light, and the other portion of the first light which is not absorbed by the transparent wavelength conversion layer 121 enters the transparent light guide layer 122 through the transparent wavelength conversion layer 121, and is then reflected back to the transparent wavelength conversion layer 121 by the light reflection structure 123 and then exits. The light exiting the wavelength conversion device 120 is finally mixed light of the first light L1 and the second light L2.

In this embodiment, the laser source 110 is a blue laser source, which is a laser semiconductor source. The laser light source 110 in fig. 1 shows one laser semiconductor light source, and in other embodiments of the present invention, a laser array light source composed of a plurality of laser diodes may be used as the laser light source.

In the present embodiment, the transparent wavelength conversion layer 121 is a fluorescent single crystal, specifically, a Ce: YAG fluorescent single crystal. The fluorescent single crystal has stable structure and high luminous efficiency, and can absorb blue light and emit yellow light. It is understood that in other embodiments of the present invention, combinations of laser light sources with other spectral characteristics and transparent wavelength conversion layers may also be used, and are not described herein.

In a modified embodiment of this embodiment, the transparent wavelength conversion layer may also be a transparent fluorescent ceramic, i.e. a composite layer of the fluorescent light-emitting material and a transparent ceramic matrix, for example, a fluorescent ceramic with transparent alumina as the ceramic matrix and a Ce: YAG light-emitting center disposed inside the ceramic matrix.

The transparent wavelength conversion layer 121 of the present embodiment has a single-layer structure of a single material, but in other embodiments, the transparent wavelength conversion layer may have a multilayer structure including two or more wavelength conversion materials.

It is noted that in the present invention, whether the wavelength converting layer is a fluorescent single crystal or a fluorescent ceramic, whether comprising a single material or multiple materials, the transparent property needs to be satisfied such that the unabsorbed first light can pass through the transparent wavelength converting layer and the transparent light guiding layer, otherwise the first light will be reflected directly near the incident surface of the wavelength converting layer as in the technical solution of fig. 8a of the background section.

In the present embodiment, the transparent light guide layer 122 is a light guide medium layer with a refractive index greater than 1. Preferably, the transparent light guide layer 122 is a sapphire layer, and has both light guide and heat conduction properties.

In this embodiment, the transparent wavelength conversion layer 121 and the transparent light guide layer 122 are connected by a glue layer (not shown), which is a transparent glue layer and has a small light absorption rate.

In another embodiment of the present invention, when the transparent wavelength conversion layer and the transparent light guide layer are made of appropriate materials, they may be integrally molded. For example, if the transparent wavelength conversion layer is a transparent fluorescent ceramic using YAG as a matrix and the transparent light guide layer is pure-phase undoped YAG, the preparation temperatures of the two layers are close to each other and the two layers can be obtained by integral molding. The mode of adopting integrated into one piece still has the additional effect-can prepare and obtain the bilayer structure of large size, then obtains the composite construction of transparent wavelength conversion layer + transparent leaded light layer of small-size through ways such as line cutting, applies to the product of small-size illumination.

In the embodiment, the light reflection structure 123 is a reflection groove, and the transparent wavelength conversion layer 121 and the transparent light guide layer 122 are disposed in the reflection groove, so that only the first surface of the transparent wavelength conversion layer 121 is not covered by the light reflection structure, thereby ensuring that the light source device 10 has a unique light emitting direction.

In the present embodiment, the light reflection structure 123 is at least partially a diffuse reflection structure, so that the divergence angle of the first light L1 incident on the diffuse reflection structure is further expanded after being diffusely reflected, and the entire first surface of the transparent wavelength conversion layer 121 can be covered, so that the first light L1 is matched with the emergent spot of the second light L2. For example, the covered surface of the transparent light guide layer 122 includes a side surface and a bottom surface, and the light reflection structure covered by at least one of the side surface and the bottom surface is a diffuse reflection structure.

The diffuse reflection structure in this embodiment is a mixed layer structure of diffuse reflection particles (e.g., white scattering particles such as alumina and titania) and glass frit, and the layer structure is obtained by mixing the both and then heating and softening/melting the mixture. In other embodiments of the present invention, the diffuse reflection structure may also be a rugged rough structure.

In this embodiment, the wavelength conversion device 120 further includes a heat sink 124 disposed outside the light reflection structure 123, and the light reflection structure 123 and the heat sink 124 are connected by a heat conductive adhesive, so as to rapidly conduct out heat generated by the transparent wavelength conversion layer 121. Further, heat dissipation devices such as heat dissipation fins, fans, thermoelectric cooling devices, etc. may be disposed on the outer side of the heat sink 124.

In the present embodiment, the light source device 10 further includes a light guide device disposed between the laser light source 110 and the wavelength conversion device 120, and configured to guide the first light L1 to the first surface of the transparent wavelength conversion layer 121, and guide and emit mixed light of the first light and the second light emitted from the first surface of the transparent wavelength conversion layer 121. Specifically, the light guiding device includes a perforated mirror 131 and a collecting lens 132, and the first light L1 from the laser source 110 passes through the small hole of the perforated mirror 131 and is converged and incident on the first surface through the collecting lens 132; then, after the mixed light of the first light L1 and the second light L2 emitted from the first surface is collected by the collecting lens 132, a small amount of light is leaked through the small hole of the perforated mirror 131, and most of the light is reflected by the perforated mirror 131 and enters the emission light path.

In other embodiments of the present invention, the perforated mirror 131 may be replaced with a small mirror or a partially coated beam splitter, and the separation of the incident light path and the outgoing light path is achieved by the difference in the etendue of the incident light and the outgoing light.

In the light source device 10 according to the first embodiment of the present invention, the transparent light guide layer is additionally disposed between the transparent wavelength conversion layer and the light reflection structure, so that the unabsorbed first light additionally passes through the optical paths of the two transparent light guide layers, and the light spots of the first light are enlarged to match with the light spots of the second light, thereby improving the color uniformity of the emergent light. As long as the transparent light guide layer is added, the color uniformity is better than that of the technical scheme without the transparent light guide layer. In order to further quantitatively determine the influence of the transparent light guide layer on the color uniformity of the emergent light, the inventor further performs experimental verification.

Fig. 7 shows the distribution of the color of the emergent spots of the wavelength conversion device without the transparent light guide layer and the wavelength conversion device with the transparent light guide layer. Specifically, the image a on the left side shows the color distribution of emergent light spots on the first surface only containing a transparent wavelength conversion layer with the thickness of 0.2mm, the center is blue, and the edge is yellow; and the b picture on the right side is the color distribution of the emergent light spots on the first surface after the transparent wavelength conversion layer with the thickness of 0.2mm is added with the transparent light guide layer with the thickness of 0.6mm, and the color distribution of the whole surface is obviously uniform.

The inventors of the present invention confirmed through further experiments that when the thickness of the transparent light guiding layer 122 is not less than 3 times the thickness of the transparent wavelength conversion layer 121, a better color uniformity improvement of the emitted light can be achieved.

Fig. 2 is a schematic structural diagram of a light source device according to a second embodiment of the invention. The light source device 20 comprises a laser light source 210 and a wavelength conversion device 220, wherein the wavelength conversion device 220 comprises a transparent wavelength conversion layer 221, a transparent light guiding layer 222 and a light reflecting structure 223.

The second embodiment is different from the first embodiment in that the light reflection structure 223 in the first embodiment is a reflective coating on the surfaces of the transparent wavelength conversion layer 221 and the transparent light guide layer 222. The reflective coating can be a metal reflective layer, such as a silver reflective film layer, an aluminum reflective film layer. The reflective coating can also be a dielectric reflective coating, i.e., a reflective film layer composed of a plurality of layer structures with different refractive indexes.

The embodiment is particularly suitable for the technical scheme of the integrated forming of the transparent wavelength conversion layer and the transparent light guide layer, the large-size double-layer structure is obtained, the small-size composite structure of the transparent wavelength conversion layer and the transparent light guide layer is obtained through the wire cutting and other modes, the side face of the composite structure is very flat, the film coating treatment can be carried out without polishing, and the low-cost mass production is easy to realize.

In addition, when the size of the wavelength conversion device is small, for example, the maximum length is not more than 1mm, the reflective groove type light reflection structure is very difficult to process, and even if the groove processing is successful, it is difficult to plate the reflective film in the fine groove. In particular, it is difficult to achieve high reflectivity in a very thin thickness for the light reflecting structure of the diffuse reflection layer. The embodiment obtains the light reflection structure not by grooving but by coating the outer surfaces of the transparent wavelength conversion layer and the transparent light guide layer which are integrally formed, thereby solving the difficult problem of the actual preparation process of the small-size wavelength conversion device and improving the practicability of the product.

For other descriptions of the optical device of this embodiment and the dimensional relationship between the devices, reference may be made to the description of the first embodiment, and further description is omitted here.

Fig. 3 is a schematic structural diagram of a light source device according to a third embodiment of the invention. The light source device 30 includes a laser light source 310 and a wavelength conversion device 320, and the wavelength conversion device 320 includes a transparent wavelength conversion layer 321, a transparent light guide layer 322, a light reflection structure 323, and a heat sink 324.

The difference between the embodiment and the first embodiment is that the transparent light guiding layer 322 further includes scattering particles 3221. The light guiding property of the transparent light guiding layer 322 is not obviously affected by adding a small amount of scattering particles 3221 in the transparent light guiding layer 322, and the light beam of the first light can be enlarged by scattering, which is favorable for realizing the enlargement of the light spot of the first light in a shorter distance.

For the description of other devices of this embodiment, reference may be made to the description of the above embodiments, and details are not repeated here. The technical solution of adding the scattering particles 3221 in the transparent light guide layer 322 of this embodiment can also be applied to the transparent light guide layer of the second embodiment.

Fig. 4 is a schematic structural diagram of a light source device according to a fourth embodiment of the invention. The light source device 40 includes a laser light source 410 and a wavelength conversion device 420. The wavelength conversion device 420 includes a transparent wavelength conversion layer 421, a transparent light guide layer 422, a light reflection structure 423, and a heat sink 424.

The difference between the present embodiment and the first embodiment is that the transparent wavelength conversion layer 421 and the transparent light guide layer 422 are not directly contacted or indirectly adhered by a glue layer, but an air space 425 is provided therebetween. In this embodiment, the light reaching the surface of the transparent wavelength conversion layer opposite to the first surface includes the first light that is not absorbed and the second light that is emitted by the transparent wavelength conversion layer. Wherein the first light is unscattered, typically light with a small divergence angle and a small incident angle; and the second light is 360 ° emitted light, including light incident angles from 0 ° to 90 °. Through setting up the air interval, can make first light direct transmission, and some second light is reflected back transparent wavelength conversion layer by the total reflection at this interface position to reduced the second light and propagated and the light loss that is brought by the reflection in transparent leaded light layer, improved the light utilization ratio of second light.

For the description of other devices of this embodiment, reference may be made to the description of the above embodiments, and details are not repeated here.

Fig. 5 is a schematic structural diagram of a light source device according to a fifth embodiment of the present invention. The light source device 50 includes a laser light source 510 and a wavelength conversion device 520. The wavelength conversion device 520 includes a transparent wavelength conversion layer 521, a transparent light guide layer 522, a light reflection structure 523, and a heat sink 524.

The light reflection structure in this embodiment is a reflection groove, and unlike the first embodiment, the reflection groove in this embodiment includes a first section and a second section. The first section of groove is close to the light emergent end and used for accommodating the transparent wavelength conversion layer 521, the second section of groove accommodates the transparent light guide layer 522, the sectional area of the first section of groove is larger than that of the second section of groove, and the transparent wavelength conversion layer 521 is fixed in the reflection groove through the size difference of the two sections of grooves.

Another major difference between the present embodiment and the first embodiment is that the transparent light guiding layer 522 in the present embodiment is an air layer. This embodiment is equivalent to disposing a cavity for the first light conduction beam expansion between the transparent wavelength conversion layer 521 and the light reflection structure, so that the emergent spots of the first light and the second light are matched.

For the description of other devices in this embodiment, reference may be made to the description of each of the embodiments above, and details are not repeated here.

Fig. 6 is a schematic structural diagram of a light source device according to a sixth embodiment of the present invention. The light source device 60 comprises a laser light source 610 and a wavelength conversion device 620, wherein the wavelength conversion device 620 comprises a transparent wavelength conversion layer 621, a transparent light guiding layer 622, a light reflecting structure 623 and a heat sink 624. The light source device 60 of the present embodiment further includes a light guiding device, specifically, a prism 633.

The difference from the above embodiments is that the first light in this embodiment is not directly incident on the first surface of the transparent wavelength conversion layer at normal incidence, but is incident obliquely on the first surface.

The first laser light emitted by the semiconductor laser has high polarization degree, when the first light obliquely enters the corresponding first surface in a P polarization state and the incident angle is the Brewster angle, no reflection occurs, and the utilization rate of the first light is the highest.

In the present invention, the first light is incident on the first surface at the brewster angle, and it can be considered that light incident within the angle error range (e.g., ± 5 °) is incident at the brewster angle.

In this embodiment, the prism 633 is arranged to guide the first light, so that the laser light source is prevented from directly emitting light toward the first surface, the light source device 60 has a higher structural compactness, the distance between the first surface and the light collection system can be further reduced, and the collection efficiency of the emitted light is improved.

For the description of the components of the wavelength conversion device 620 of this embodiment, reference may be made to the description of the above embodiments, which are not repeated herein.

The embodiments in the present description are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other.

The above description is only an embodiment of the present invention, and not intended to limit the scope of the present invention, and all modifications of equivalent structures and equivalent processes performed by the present specification and drawings, or directly or indirectly applied to other related technical fields, are included in the scope of the present invention.

Claims

1. A light source device, comprising:

a laser light source for emitting first light;

the wavelength conversion device is arranged on a light path of the first light, and comprises a transparent wavelength conversion layer and a transparent light guide layer which are sequentially arranged along the incident direction of the first light, wherein the transparent wavelength conversion layer comprises a first surface which is a light incident surface and a light emergent surface of the wavelength conversion device;

the wavelength conversion device also comprises a light reflection structure which is arranged on the surface of the transparent light guide layer far away from the transparent wavelength conversion layer;

the transparent wavelength conversion layer absorbs part of the first light and emits second light with a wavelength range different from that of the first light, part of the first light enters the transparent light guide layer through the transparent wavelength conversion layer, and emergent light of the wavelength conversion device is mixed light of the first light and the second light.

2. The light source device according to claim 1, wherein the transparent wavelength conversion layer is a fluorescent single crystal or a transparent fluorescent ceramic.

3. The light source device according to claim 1 or 2, wherein the transparent light guide layer is a light guide medium layer having a refractive index greater than 1.

4. The light source device of claim 3, wherein an air space is disposed between the transparent wavelength conversion layer and the transparent light guide layer.

5. The light source device of claim 3, wherein the transparent wavelength conversion layer is integrally formed with the transparent light guide layer, or the transparent wavelength conversion layer and the transparent light guide layer are connected by a glue layer.

6. The light source device of claim 3, wherein the transparent light guiding layer further comprises scattering particles.

7. The light source device according to claim 1 or 2, wherein the transparent light guide layer is an air layer.

8. The light source device according to claim 1 or 2, wherein a thickness of the transparent light guiding layer is not less than 3 times a thickness of the transparent wavelength conversion layer.

9. The light source device of claim 1, wherein the light reflecting structure is a reflective groove, and the transparent wavelength conversion layer and the transparent light guide layer are disposed in the reflective groove.

10. The light source device of claim 1, wherein the light reflecting structure is at least partially a diffuse reflecting structure.

11. The light source device according to claim 1, wherein the first light is polarized light, and the first light is obliquely incident to the first surface at a brewster angle.