CN111103748A

CN111103748A - Wavelength conversion device and light source system

Info

Publication number: CN111103748A
Application number: CN201811270828.3A
Authority: CN
Inventors: 戴达炎; 金明富; 王晓秋; 李屹
Original assignee: Appotronics Corp Ltd
Current assignee: Shenzhen Appotronics Corp Ltd
Priority date: 2018-10-29
Filing date: 2018-10-29
Publication date: 2020-05-05
Also published as: WO2020088160A1

Abstract

The invention provides a wavelength conversion device and a light source system, wherein the wavelength conversion device comprises: a substrate; a reflective layer disposed on the substrate; the heat conduction layer is stacked on one side of the reflection layer, which is far away from the base body; the wavelength conversion layer is stacked on one side of the heat conduction layer, which is far away from the reflection layer, and is used for receiving exciting light and emitting excited light; and the bonding layer is arranged around the peripheral walls of the reflecting layer and the heat conducting layer, is positioned below the wavelength conversion layer and is used for bonding the wavelength conversion layer and the base body. With the present invention, the performance of the wavelength conversion device is improved and the service life of the wavelength conversion device is extended.

Description

Wavelength conversion device and light source system

Technical Field

The present invention relates to the field of optical technologies, and in particular, to a wavelength conversion device and a light source system.

Background

In recent years, the technology of applying laser light sources to the display field is more and more mature, and the laser light sources excite fluorescent materials to generate monochromatic light, so that the LED display panel has the advantages of high conversion efficiency, no efficiency dip, high brightness, small volume, good controllability and the like. The type selection and processing technology of the fluorescent material and the material selection and processing technology of the reflective coating have important influence on the light emitting efficiency of the light source. The reflection layer technology commonly used in the industry at present is generally divided into two types: firstly, combining a reflecting layer and a luminous layer by using an inorganic non-metallic material through a specific forming process; and secondly, directly bonding the light-emitting layer and the reflecting layer by using an organic adhesive. Both of the above two approaches have certain limitations: the former uses inorganic materials but the thermal conductivity of the product itself is relatively low due to limitations of the molding process and the thermal conductivity of the inorganic binder. The inorganic binder occupies a considerable volume ratio in the whole material system, and the heat dissipation performance of the product is directly limited by the heat conductivity of the inorganic binder. The latter uses organic adhesive, although the process is simple and easy to operate, the adhesive of the reflecting layer and the luminescent layer is organic, the aging of the organic can be accelerated by strong light radiation and thermal shock for a long time, and the application of the process to high-power products is limited due to the poor temperature resistance and thermal conductivity of the organic. Meanwhile, most of adhesives on the market are epoxy resin, the adhesives can form a porous structure along with the aging of the epoxy resin in the long-term use process of equipment, and impurities and moisture in the air can slowly permeate into the reflecting layer and the light-emitting layer to influence the light-emitting efficiency of the fluorescent material and the reflectivity of the reflecting material.

Disclosure of Invention

In view of the above, there is a need for a wavelength conversion device that can simultaneously solve or circumvent the problems of the above two processes.

The present invention provides a wavelength conversion device, comprising: a substrate; a reflective layer disposed on the substrate; the heat conduction layer is stacked on one side of the reflection layer, which is far away from the base body; the wavelength conversion layer is stacked on one side of the heat conduction layer, which is far away from the reflection layer, and is used for receiving exciting light and emitting excited light; and the bonding layer is arranged around the peripheral walls of the reflecting layer and the heat conducting layer, is positioned below the wavelength conversion layer and is used for bonding the wavelength conversion layer and the base body.

The invention also provides a light source system which comprises the wavelength conversion device.

According to the wavelength conversion device and the light source system provided by the invention, the reflecting layer is sealed by the wavelength conversion layer and the bonding layer together, so that the reflecting layer is isolated from being contacted with the outside air, the reflecting layer is protected, and the reflecting layer is prevented from being oxidized or vulcanized. Moreover, the heat conducting layer is filled between the wavelength conversion layer and the reflecting layer, so that the air content between the wavelength conversion layer and the reflecting layer is reduced, the heat conducting layer can quickly transfer heat generated by the wavelength conversion layer to the base body, and the heat dissipation efficiency is improved. In addition, the bonding layer is bonded to the inner edge area and the outer edge area of the wavelength conversion layer, so that the area irradiated by exciting light on the wavelength conversion layer is avoided, the influence of thermal shock between the lighting and unlighting of the wavelength conversion device on the organic binder is reduced, and the risk of organic binder aging caused by direct light radiation is reduced. Thus, the performance of the wavelength conversion device is improved and the lifetime of the wavelength conversion device is extended.

Drawings

Fig. 1 is a partial perspective view of a wavelength conversion device according to a first embodiment of the present invention.

Fig. 2 is a cross-sectional view of the wavelength conversion device of fig. 1 taken along II-II.

Fig. 3 is a cross-sectional view of a wavelength conversion device according to a second embodiment of the present invention.

Fig. 4 is a cross-sectional view of a wavelength conversion device according to a third embodiment of the present invention.

Fig. 5 is a schematic diagram of a light source system according to an embodiment of the invention.

Description of the main elements

Wavelength conversion device	100、200、300
		Base body	110、210、310
Reflective layer	120
		Heat conducting layer	130
Wavelength conversion layer	140、240、340
		Adhesive layer	150、350
Mounting hole	112
		First containing groove	114、314
Head space	121
		Driving member	170、270
Heat radiation fin	280
		Cover plate	390
Second containing groove	319
		Step surface	318
Light source system	400

The following detailed description will further illustrate the invention in conjunction with the above-described figures.

Detailed Description

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention, but the present invention may be practiced in other ways than those specifically described and will be readily apparent to those of ordinary skill in the art without departing from the spirit of the present invention and the scope of the present invention is therefore not limited to the specific embodiments disclosed below.

Referring to fig. 1 and fig. 2, fig. 1 is a partial perspective view of a wavelength conversion device 100 according to a first embodiment of the present invention, and fig. 2 is a cross-sectional view of the wavelength conversion device 100 shown in fig. 1 along II-II. The wavelength conversion device 100 includes a base 110, a reflective layer 120, a thermally conductive layer 130, a wavelength conversion layer 140, and an adhesive layer 150. The substrate 110 is a heat dissipation substrate, and the reflective layer 120 is disposed on the substrate 110. The heat conducting layer 130 is stacked on a side of the reflective layer 120 facing away from the substrate 110. The wavelength conversion layer 140 is stacked on a side of the heat conduction layer 130 away from the reflection layer 120, and is configured to receive the excitation light and emit the excited light. The adhesive layer 150 is disposed around the reflective layer 120 and the inner and outer peripheral walls of the heat conductive layer 130, and is located below the wavelength conversion layer 140, for adhering the wavelength conversion layer 140 and the base 110. The inner peripheral walls of the reflective layer 120 and the heat conductive layer 130 are relatively close to the middle position of the base 110, and the outer peripheral walls of the reflective layer and the heat conductive layer are relatively close to the edge position of the base 110.

The substrate 110 provides support and transmission for the entire wavelength conversion device 100, as well as providing a dynamic balance adjustment location, and for heat dissipation. The substrate 110 has a substantially circular ring shape and includes an upper surface and a lower surface opposite to each other. The central portion of the base 110 is provided with a mounting hole 112. The upper surface of the base 110 is recessed toward the lower surface to form a first receiving groove 114. The first receiving groove 114 extends along the circumferential direction of the base 110 and has a substantially circular ring shape.

The reflective layer 120 is substantially circular and is received in the first receiving groove 114. The bottom surface of the reflective layer 120 contacts the bottom wall of the first receiving groove 114, and two side surfaces of the reflective layer 120 are spaced from corresponding side walls of the first receiving groove 114 by a predetermined distance. Each side surface of the reflective layer 120, the side wall corresponding to the first receiving groove 114, and the bottom wall of the first receiving groove 114 surround to form a reserved space 121. Specifically, a side surface of the reflective layer 120 close to the middle of the substrate 110, a side wall corresponding to the first receiving groove 114, and a bottom wall of the first receiving groove 114 surround to form a reserved space 121, and another side surface of the reflective layer 120 opposite to the side surface close to the edge of the substrate 110, a side wall corresponding to the first receiving groove 114, and a bottom wall of the first receiving groove 114 surround to form another reserved space 121. The reflective layer 120 is made of a high reflective material, such as a metal material or an inorganic non-metal material. Preferably, the reflective layer 120 is made of a metal material, such as specular metallic silver, aluminum, or the like.

The heat conducting layer 130 is stacked on the top surface of the reflective layer 120 and is received in the first receiving groove 114. The thermally conductive layer 130 has substantially the same dimensions as the reflective layer 120. The heat conducting layer 130 is formed by filling a transparent powder material with high thermal conductivity, such as flake boron nitride, aluminum oxide, aluminum nitride or silicon nitride. In this embodiment, the thermal conductivity of the heat conductive layer 130 is lower than the thermal conductivity of the base 110.

The wavelength conversion layer 140 is stacked on a side of the heat conduction layer 130 away from the reflection layer 120, and is accommodated in the first accommodation groove 114, and covers the reserved space 121. The wavelength conversion layer 140 is substantially annular, and the lateral width of the wavelength conversion layer 140 is greater than the lateral widths of the reflective layer 120 and the thermally conductive layer 130. The wavelength conversion layer 140 is made of a wavelength conversion material with high luminous efficiency and high thermal conductivity, such as a pure phase fluorescent ceramic or a complex phase fluorescent ceramic. The thermal conductivity of the fluorescent ceramic is 12-24 w/m.s. The wavelength conversion layer 140 is used for receiving the excitation light and generating excited light in lambertian form of at least one color under excitation of the excitation light. For example, the wavelength conversion layer 140 receives the blue excitation light and generates the excited light of other colors such as red, green, and yellow. The laser light emitted from the wavelength conversion layer 140 passes through the heat conduction layer 130, then enters the reflection layer 120, is reflected by the reflection layer 120, and then sequentially exits through the heat conduction layer 130 and the wavelength conversion layer 140. The heat generated in the excitation light irradiation region of the wavelength conversion layer 140 can be rapidly conducted to the substrate 110 through the heat conductive layer 130.

Preferably, the base 110 has a thermal expansion coefficient of 2.81 × 10^-6～23×10^-6A coefficient of thermal expansion of the wavelength conversion layer 140 of 2.21 x 10/° C^-6～7.6×10^-6V. C. Considering that the thermal expansion coefficient of the base 110 is relatively greater than that of the wavelength conversion layer 140, a gap is formed between the sidewall of the wavelength conversion layer 140 and the sidewall of the first receiving groove 114. In this embodiment, the gap is 0.05-0.25 mm. The organic binder in the adhesive layer 150 may overflow into the gap during normal production.

The adhesive layer 150 is accommodated in the reserved space 121 and adheres the wavelength conversion layer 140 to the substrate 110. Further, the adhesive layer 150 adheres the wavelength conversion layer 140, the reflective layer 120, the heat conductive layer 130 and the substrate 110, and the adhesive layer 150 is disposed on the edge region of the wavelength conversion layer 140 close to the inner side and the edge region close to the outer side, and covers the edges of the reflective layer 120 and the heat conductive layer 130. The edge region of the wavelength conversion layer 140 refers to a space formed by the substrate 110 and a side of the wavelength conversion layer 140 facing the heat conduction layer 130, and the space is located at the peripheral walls of the reflection layer 120 and the heat conduction layer 130. The space is an inner edge region when it is close to the axial center of the wavelength conversion device 100, and the space is an outer edge region when it is far from the axial center of the wavelength conversion device 100. In this embodiment, the inner side of the wavelength conversion layer 140 and other components refers to a position near the middle of the base 110, and the outer side of the wavelength conversion layer 140 and other components refers to a position near the edge of the base 110. The adhesive layer 150 is made of an organic adhesive. Since the bonding layers 150 are disposed at the inner and outer edges of the wavelength conversion layer 140, the regions of the wavelength conversion layer 140 irradiated by the excitation light are avoided, the influence of thermal shock between the lighting and unlighting of the wavelength conversion device 100 on the organic binder can be reduced, and the risk of the organic binder aging due to direct light radiation can be reduced. Meanwhile, the organic binder can well eliminate the stress problem caused by the large-area bonding of the wavelength conversion layer 140 and the reflective layer 120 made of different materials in a solid state.

Preferably, the wavelength conversion device 100 further comprises a driving member 170. The driving member 170 is connected to the base 110 for driving the base 110 to rotate. Specifically, the driving member 170 is partially received in the mounting hole 112 for driving the base 110 to rotate around the central axis thereof. In this embodiment, the driving member 170 is a motor.

In the wavelength conversion device 100 according to the first embodiment of the present invention, the wavelength conversion layer 140 and the adhesive layer 150 jointly cover the reflective layer 120, so as to isolate the reflective layer 120 from the outside air, thereby protecting the reflective layer 120 and preventing the reflective layer 120 from being oxidized or vulcanized. Moreover, the heat conduction layer 130 is filled between the wavelength conversion layer 140 and the reflection layer 120, so that the air content between the wavelength conversion layer 140 and the reflection layer 120 is reduced, and the heat conduction layer 130 can quickly transfer heat generated by the wavelength conversion layer 140 to the base body 110, so that the heat dissipation efficiency is improved. In addition, the bonding layers 150 are respectively bonded to the inner edge region and the outer edge region of the wavelength conversion layer 140, so as to avoid the region irradiated by the excitation light on the wavelength conversion layer 140, reduce the influence of thermal shock between the lighting and unlighted wavelength conversion devices 100 on the organic binder, and reduce the risk of aging of the organic binder caused by direct light radiation.

Referring to fig. 3, fig. 3 is a schematic cross-sectional view of a wavelength conversion device 200 according to a second embodiment of the invention. The wavelength conversion device 200 has substantially the same structure as the wavelength conversion device 100 of the first embodiment, that is, the above description of the wavelength conversion device 100 can be substantially applied to the wavelength conversion device 200, and the difference between them is mainly that: the wavelength conversion device 200 also includes heat fins 280.

Specifically, the heat dissipation fins 280 are disposed on the second surface of the base 210. When the base 210 rotates, strong convection is generated between the heat dissipation fins 280 and the air, so that heat on the base 210 is quickly dissipated, and the heat dissipation efficiency is improved; meanwhile, the heat on the surface of the driving member 270 and the heat radiation of the wavelength conversion layer 240 can be reduced, the thermal quenching phenomenon of the wavelength conversion material on the wavelength conversion layer 240 is prevented, and the light extraction efficiency is reduced.

Preferably, the heat sink fins 280 are formed by removing a portion of the base 210, such as by cutting, for reducing the weight of the base 210, saving the utilization rate of the rated load of the driving member 270, and improving the reliability of the use of the driving member 270.

Referring to fig. 4, fig. 4 is a schematic cross-sectional view of a wavelength conversion device 300 according to a third embodiment of the invention. The wavelength conversion device 300 has substantially the same structure as the wavelength conversion device 200 of the second embodiment, that is, the above description of the wavelength conversion device 200 can be substantially applied to the wavelength conversion device 300, and the difference between them is mainly that: the wavelength conversion device 300 further includes a cover plate 390.

Specifically, the cover plate 390 is disposed on the base 310 and above the wavelength conversion layer 340, and is used for fixing the wavelength conversion layer 340 in a sealing manner. Preferably, a second receiving groove 319 is formed in the upper surface of the base body 310 so as to be recessed toward the lower surface, and the second receiving groove 319 extends in the circumferential direction of the base body 310. The first receiving groove 314 is formed by partially recessing a bottom wall of the second receiving groove 319 toward a lower surface of the base 310. The lateral width of the second receiving groove 319 is greater than the lateral width of the first receiving groove 314, so that a step surface 318 is formed at the connection position of the second receiving groove 319 and the first receiving groove 314. In this embodiment, the step surface 318 is a plane and is close to the edge of the substrate 310. In another embodiment, the step surface 318 is located near a middle portion of the base 310. In yet another embodiment, the number of the step surfaces 318 is two, one near the edge of the base 310 and the other near the middle of the base 310. The cover plate 390 is fixedly received in the second receiving groove 319, and covers the wavelength conversion layer 340 in the first receiving groove 314, so as to prevent the wavelength conversion layer 340 from falling off from the adhesive layer 350 under a strong centrifugal force during a high-speed rotation process, and further fix the wavelength conversion layer 340 on the substrate 310. In another embodiment, the cover plate 390 covers the wavelength conversion layer 340 and a central position of the base body 310 surrounded by the wavelength conversion layer 340.

Preferably, the cover plate 390 is made of a high temperature resistant material with a specific refractive index, which can change the angle of the emergent light of the wavelength conversion layer 340, so that the emergent light is more beneficial to collection.

Referring to fig. 5, a schematic diagram of a light source system is shown, the light source system 400 uses the

wavelength conversion device

100, 200, or 300 described in the above embodiments to convert illumination light, and the light source system 400 can be applied to a projection system.

The foregoing embodiments are merely illustrative of the principles of this invention and are not to be construed as limiting, various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A wavelength conversion device, comprising:

a substrate;

a reflective layer disposed on the substrate;

the heat conduction layer is stacked on one side of the reflection layer, which is far away from the base body;

the wavelength conversion layer is stacked on one side of the heat conduction layer, which is far away from the reflection layer, and is used for receiving exciting light and emitting excited light; and

and the bonding layer is arranged around the peripheral walls of the reflecting layer and the heat conducting layer, is positioned below the wavelength conversion layer and is used for bonding the wavelength conversion layer and the base body.

2. The wavelength conversion device according to claim 1, wherein the base defines a first receiving cavity, and the reflective layer, the heat conductive layer and the wavelength conversion layer are sequentially disposed in the first receiving cavity.

3. The wavelength conversion device according to claim 2, wherein a gap is provided between the wavelength conversion layer and a sidewall of the first receiving groove.

4. The wavelength conversion device according to claim 2, further comprising a cover plate disposed on the base and covering the first receiving groove.

5. The wavelength conversion device according to claim 4, wherein a second receiving groove is formed in the base body in a recessed manner, the first receiving groove is formed in a recessed manner by a part of a bottom wall of the second receiving groove, and the cover plate is received in the second receiving groove.

6. The wavelength conversion device according to claim 1, wherein the base is provided with heat dissipating fins.

7. The wavelength conversion device according to claim 6, wherein the heat sink fins are formed by removing a portion of the base.

8. The wavelength conversion device of claim 1, further comprising a driving member coupled to the substrate for driving the substrate to rotate.

9. The wavelength conversion device according to any one of claims 1 to 8, wherein the wavelength conversion layer is made of a pure phase fluorescent ceramic or a complex phase fluorescent ceramic, the reflective layer is made of a metal, and the adhesive layer is made of an organic binder.

10. The wavelength conversion device according to any one of claims 1 to 8, wherein the thermally conductive layer is made of boron nitride, aluminum oxide, aluminum nitride, or silicon nitride.

11. A light source system comprising the wavelength conversion device according to any one of claims 1 to 10.