CN205720746U - A kind of reflection unit and relevant wavelength conversion equipment, colour wheel and light-source system - Google Patents

Abstract

The utility model discloses a reflection device, a related wavelength conversion device, a color wheel and a light source system, wherein the reflection device includes a ceramic substrate and a diffuse reflection glass layer located on the first surface of the ceramic substrate, and the diffuse reflection glass layer includes The second surface of the ceramic substrate is a ceramic body with a dense structure; for the same incident light, the three-dimensional divergence angle of the reflected light formed by the first surface is smaller than the three-dimensional divergence angle of the reflected light formed by the second surface; the thickness of the diffuse reflection glass layer is between Between 0.04mm and 0.15mm. The reflection device of the utility model not only solves the problem of cracking when the diffuse reflection glass layer is thick, but also does not change its diffuse reflection characteristics.

Description

A reflection device and related wavelength conversion device, color wheel and light source system

technical field

The utility model relates to the technical field of illumination and display, in particular to a reflection device, a related wavelength conversion device, a color wheel and a light source system.

Background technique

Under the existing laser display technology, with the gradual increase of laser power, the heat generated by the reflection device due to the absorption of laser light is increasing, which seriously affects the service life of the display device. come higher.

In the prior art, there is a highly reflective ceramic body with a dense structure, and the reflectivity of this high reflective ceramic body is relatively high, which can meet the requirements for use. However, since laser light is coherent light, the light reflected by this highly reflective ceramic body still maintains a certain degree of coherence, which makes it easy to generate speckle in the displayed image, thereby seriously affecting user experience.

To this end, researchers have developed another reflector structure, as shown in Figure 1, which consists of white particles (such as particles with higher whiteness such as alumina, titanium oxide, and zirconia) and glass (such as silicate glass). , borate glass, etc.) glass body composed of a diffuse reflective glass layer S1 and an aluminum nitride ceramic substrate S2 for carrying the diffuse reflective glass layer S1 and for heat dissipation. Since the glass is transparent, the reflective device structure allows the laser light to enter the diffuse reflective glass layer for multiple scattering reflections before exiting. Its diffuse reflective characteristics are much better than those of densely structured high-reflective ceramics that only reflect on the surface layer. In this reflective structure, the reflectivity of the aluminum nitride ceramic substrate S2 is not high, and its main function is to serve as a bearing and heat dissipation substrate during the preparation and use of the diffuse reflection glass layer S1, so the reflectivity is mainly determined by the diffuse reflection glass layer Provided by S1. To achieve the reflectivity that meets the application, the thickness of the diffuse reflective glass layer needs to be sufficient. However, due to the difference in coefficient of thermal expansion between the diffuse reflection glass layer and the ceramic carrier substrate, the diffuse reflection glass layer that is too thick is easy to crack during sintering, so that the yield rate of the reflective structure is very low. Therefore, a new type of reflection device needs to be developed urgently.

Utility model content

The utility model provides a reflection device which solves the problem of cracking of the diffuse reflection glass layer without changing its diffuse reflection characteristics, and provides a related wavelength conversion device, a color wheel and a light source system on this basis.

The utility model is realized through the following technical solutions:

According to the first aspect of the utility model, the utility model provides a reflection device, which includes a ceramic substrate, and also includes a diffuse reflection glass layer located on the first surface of the ceramic substrate, and the diffuse reflection glass layer includes a glass layer far away from the ceramic substrate. On the second surface, the above-mentioned ceramic substrate is a ceramic body with a dense structure;

For the same incident light, the three-dimensional divergence angle of the reflected light formed by the above-mentioned first surface is smaller than the three-dimensional divergence angle of the reflected light formed by the above-mentioned second surface, wherein the three-dimensional divergence angle of a light beam is that the light intensity of the light beam is not less than that of the light beam The solid angle enclosed by the area of 50% of the central light intensity;

The thickness of the diffuse reflection glass layer is between 0.04 mm and 0.15 mm.

As a preferred solution of the present invention, the thickness of the diffuse reflection glass layer is between 0.08 mm and 0.12 mm.

As a preferred solution of the present invention, the diffuse reflection glass layer is a diffuse reflection layer composed of white particles and glass.

As a preferred solution of the present invention, the porosity of the ceramic substrate is less than or equal to 15%.

As a preferred solution of the present invention, the ceramic substrate is selected from one of alumina ceramic substrates, zirconia ceramic substrates, boron nitride ceramic substrates, and zirconia-doped alumina composite ceramic substrates.

As a preferred solution of the present utility model, the above-mentioned ceramic substrate is a composite ceramic substrate of zirconia doped with alumina.

As a preferred solution of the present invention, the thickness of the ceramic substrate is greater than 0.5mm.

According to the second aspect of the utility model, the utility model provides a wavelength conversion device, including a luminous layer and a reflective layer, wherein the reflective layer includes the reflective device as in the first aspect, and the luminescent layer is located on the diffuse reflective glass layer. On the second surface, the above-mentioned light-emitting layer is used to convert the light incident on the light-emitting layer into light of different wavelengths.

According to the third aspect of the utility model, the utility model provides a color wheel, including a wavelength conversion area and a reflection area, wherein the reflection area includes a reflection device as in the first aspect, and the wavelength conversion area and the reflection area are in the color wheel The surfaces are stitched together to form a ring shape.

According to the fourth aspect of the utility model, the utility model provides a light source system, including the color wheel as in the third aspect, and also includes an excitation light source and a driving device, the excitation light source is used to emit excitation light to irradiate the color wheel The above-mentioned driving device is used to drive the above-mentioned color wheel to rotate, so that the wavelength conversion region and the reflective region on the above-mentioned color wheel receive the irradiation of excitation light periodically.

The reflection device of the present utility model combines a ceramic substrate with a smaller three-dimensional divergence angle of surface reflected light with a diffuse reflection glass layer with a larger three-dimensional divergence angle of surface reflected light. Since the three-dimensional divergence angle of surface reflected light of the ceramic substrate is small, Its density is higher than that of the non-glass part of the diffuse reflection glass layer, so that the ceramic substrate has a higher reflectivity, and the ceramic body with this dense structure replaces the existing aluminum nitride substrate, so that even if the thickness of the diffuse reflection glass layer is thinned Thickness also does not affect overall reflectivity. The utility model not only solves the problem of cracking when the diffuse reflection glass layer is thicker, but also ensures that the reflection device has good diffuse reflection characteristics by using the composite emission structure of the ceramic substrate and the diffuse reflection glass layer.

Description of drawings

FIG. 1 is a schematic structural view of a reflector in the prior art;

Fig. 2 is a schematic structural view of a reflection device according to an embodiment of the present invention;

FIG. 3 is a schematic structural diagram of a wavelength conversion device according to an embodiment of the present invention;

Fig. 4 is a structural schematic diagram of a color wheel according to an embodiment of the present invention.

Explanation of reference signs:

S1: Diffuse reflective glass layer;

S2: ceramic substrate;

S3: ceramic substrate;

S4: light-emitting layer;

S5: wavelength conversion area;

S6: Reflective area.

detailed description

The utility model will be described in further detail below through specific embodiments in conjunction with the accompanying drawings.

FIG. 1 shows the structure of a reflective device in the prior art, including a diffuse reflective glass layer S1 sintered on a high reflective substrate and a ceramic substrate S2 for sintering the diffuse reflective glass layer S1 . Among them, the diffuse reflection glass layer S1 is generally composed of white particles (such as particles with relatively high whiteness such as alumina, titanium oxide, and zirconia) and glass (such as silicate glass, borate glass, etc.); ceramic substrate S2 Usually aluminum nitride ceramics. The thickness of the diffuse reflection glass layer S1 is more than 0.15 mm, and the diffuse reflection glass layer will crack during the sintering process because the S1 is too thick.

Aiming at the problem that the diffuse reflection glass layer is too thick and easy to crack in the prior art, the utility model provides a novel reflection device. Fig. 2 shows the structure of a reflection device according to an embodiment of the present invention, which includes a ceramic substrate S3 and a diffuse reflection glass layer S1 on the ceramic substrate S3, wherein the ceramic substrate S3 is a ceramic body with a dense structure. The diffuse reflection glass layer S1 is located on the first surface of the ceramic substrate S3, and the diffuse reflection glass layer S1 further includes a second surface away from the ceramic substrate S3, and the second surface is the light incident surface of the reflection device. For the same incident light, the three-dimensional divergence angle of the reflected light formed by the above-mentioned first surface is smaller than the three-dimensional divergence angle of the reflected light formed by the above-mentioned second surface, wherein the three-dimensional divergence angle of the light beam is that the light intensity of the light beam is not less than the center of the light beam For the solid angle enclosed by the area with 50% of the light intensity, the solid divergence angle of the first surface is small, which means that the diffuse reflection performance of the first surface is poor, and also means that the density of the ceramic substrate is high.

In the present invention, the porosity of the dense ceramic body used as the ceramic substrate is generally preferably below 15%, and such a porosity can ensure a relatively high reflectivity. At the same time, the high density of the ceramic substrate also means that its thermal conductivity is better than that of low-density ceramics of the same material, which makes up for the problem of reduced thermal conductivity caused by the replacement of aluminum nitride ceramics with high thermal conductivity. Generally speaking, when the material of the ceramic substrate is certain, the reflectivity of the ceramic substrate is positively correlated with its density, and negatively correlated with the porosity, while the porosity is positively correlated with the diffuse reflection performance, so the reflectivity of the ceramic substrate is related to Diffuse performance is inversely proportional. Therefore, the lower the porosity, the more conducive to the improvement of the reflectivity. The preferred solution of the utility model selects a ceramic substrate with a porosity below 15% to ensure that the reflectivity is high enough, so there is no need to increase the thickness of the diffuse reflection glass layer, and the thickness A diffuse reflective glass layer between 0.04 mm and 0.15 mm is sufficient to provide the required diffuse reflective performance. In the present invention, the porosity refers to the percentage of the pore volume in the bulk material to the total volume of the material in the natural state according to the usual definition in the art.

The utility model adopts a high-reflectivity ceramic substrate with a dense structure (the reflectivity is higher than that of aluminum nitride ceramics) to replace the existing aluminum nitride ceramics, thereby improving the reflectivity. Then reduce the thickness of the diffuse reflection glass layer S1 to solve the cracking problem of the diffuse reflection glass layer. Since the reflectivity of the ceramic substrate is improved, even if the diffuse reflection glass layer is thinned, the overall reflectivity is not affected, and the scattering angle also meets the requirements. .

In the utility model, the diffuse reflection glass layer S1 is on the dense structure ceramic body substrate, and the same as the prior art, the diffuse reflection glass layer S1 is also made of white particles (such as particles with higher whiteness such as alumina, titanium oxide, and zirconia) ) and glass (such as silicate glass, borate glass, etc.), the difference is that the thickness of the diffuse reflection glass layer S1 in the present invention is less than 0.15 mm, specifically between 0.04 mm and 0.15 mm. When the thickness of the diffuse reflection glass layer is greater than 0.15mm, due to the large difference between the thermal expansion coefficient of the diffuse reflection glass layer and that of the ceramic substrate, under the action of thermal stress, the diffuse reflection glass layer is prone to cracking during the process. .

Generally speaking, the thickness of the diffuse reflection glass layer S1 in the present invention should be at least 0.04 mm, and if the thickness is less than 0.04 mm, its diffuse reflection characteristics may be affected. More preferably, the thickness of the diffuse reflection glass layer S1 is between 0.08mm-0.12mm, such as 0.09mm, 0.10mm, 0.11mm, 0.082-0.112mm, 0.093-0.108mm and so on. In this utility model, the diffuse reflection glass layer S1 is a mixed layer of white particles and glass powder. Since the glass layer is transparent, it can be regarded as a gap with a refractive index greater than 1, and light is scattered/reflected at the interface between the white particles and the glass. . Therefore, in the case of the same volume ratio of white particles to glass, the greater the thickness of the diffuse reflection glass layer S1, the more times the light undergoes scattering/reflection in the diffuse reflection glass layer S1, and the more the laser is decohered. Big. When the thickness of the diffuse reflection glass layer S1 is too small, it is possible that laser light directly penetrates the diffuse reflection glass layer S1 without being scattered, so that the emitted light still has a certain degree of coherence.

Based on the principle of the utility model, any ceramic substrate whose reflectivity is substantially higher than that of aluminum nitride ceramics (the blue light reflectivity of aluminum nitride is poor, and its reflected light to white light is reddish) can be used as the utility model. Ceramic substrate S3. Such ceramic substrates are, for example, one of alumina ceramic substrates, zirconia ceramic substrates, boron nitride ceramic substrates, and zirconia-doped alumina composite ceramic substrates. More preferably, one of an alumina ceramic substrate and a zirconia-doped alumina composite ceramic substrate. Most preferably, a composite ceramic substrate of zirconia doped alumina. In one embodiment of the present invention, a composite ceramic made of zirconia doped with alumina is used as the ceramic substrate S3.

Generally speaking, the thickness of the ceramic substrate is not particularly limited, but in order to provide sufficient mechanical strength, the thickness of the ceramic substrate is preferably greater than 0.5mm, such as 0.6mm, 0.8mm, 1.0mm, 2.0mm, 5.0mm, 0.7-3mm, etc. If the thickness of the ceramic substrate is less than 0.5 mm, its mechanical strength is poor and it is easily damaged.

The following examples and comparative examples are used to compare the blue light reflection performance and the sintered state of the diffuse reflection glass layer between the reflective device of the present invention and the reflective device in the prior art. The results show that the reflection device of the present invention not only solves the problem of cracking when the diffuse reflection glass layer is thicker, but also does not change its diffuse reflection characteristics.

In the following examples and comparative examples, the diffuse reflection glass layer S1 is made of aluminum oxide (0.1-1 micron in particle size) as white particles, and silicate glass as glass bonding particles. The reflective glass layers S1 are all made of the same material, and the difference is that the thicknesses of the diffuse reflective glass layers S1 are different. The ceramic substrate S2 is made of aluminum nitride ceramics; the ceramic substrate S3 is made of composite ceramics doped with zirconia and alumina. The existing device is a combination of diffuse reflection glass layer S1+aluminum nitride ceramics.

Table 1 shows the data of the reflective devices of the embodiment and the comparative example in terms of S1 thickness, blue light power, power ratio (calculated based on the existing device) and the sintered state of the diffuse reflective glass layer. Use the blue light of the same power to irradiate the reflecting device, and then collect the reflected light. The blue light power in the list is the power of the reflected light, and the ratio in the list is the ratio of the reflected blue light power of the reflecting device to the blue light power of the existing device.

Table 1

The results show that: the S1 thickness of the existing device is relatively large, although the blue light power is high, but the diffuse reflection glass layer is easy to crack when sintered; the S1 thickness of Comparative Examples 1-3 is small, although the diffuse reflection glass layer is sintered without cracking, but the blue light The power is low, which cannot meet the performance requirements; and although the thickness of S1 in Examples 1-3 is small, the diffuse reflection glass layer will not crack when sintered, and the blue light power is high, which can meet the performance requirements. In addition, it can be seen from Examples 1-3 that as the thickness of S1 increases, the blue light power increases significantly. It can be seen that on the premise that the diffuse reflection glass layer does not crack during sintering, increasing the thickness of S1 is conducive to improving the blue light power performance.

The utility model also provides a wavelength conversion device comprising the above-mentioned reflective device, as shown in Figure 3, comprising a luminous layer S4 and a reflective layer, wherein the reflective layer comprises the reflective device of the above-mentioned embodiment, and the reflective layer is composed of a diffuse reflection glass layer S1 And ceramic substrate S3 composition. The light-emitting layer includes a wavelength conversion material for converting light incident on the light-emitting layer into light of different wavelengths. The light-emitting layer can be phosphor glass sintered from phosphor powder and glass powder, or phosphor ceramic. In some application scenarios where the incident light intensity is not high, the luminescent layer can also be a quantum dot luminescent layer or an organic phosphor layer composed of phosphor powder and silica gel.

The utility model also provides a color wheel, as shown in FIG. 4 , including a wavelength conversion area S5 and a reflection area S6 , and the two areas are spliced on the surface of the color wheel to form a circular ring. Wherein, the reflective area includes the reflective device in the above embodiment, which is a two-layer structure composed of a diffuse reflective glass layer and a ceramic substrate, and the wavelength conversion area includes a light emitting layer and a reflective layer. Wherein, the reflective layer in the wavelength conversion region can be either the reflective device in the above embodiment (a two-layer structure composed of a diffuse reflective glass layer and a ceramic substrate), or other reflective devices. For example, in the color wheel of this embodiment, the reflective layer in the wavelength conversion region can be a single-layer structure of ceramic substrate S3. This is because the light emitting layer in the wavelength conversion region itself has a scattering function, and there is no need to further increase the diffuse reflection glass layer S1 to enhance Scattering effect, so that the surface of the light-emitting layer in the wavelength conversion region is flush with the surface of the diffuse reflection glass layer in the reflection region.

The utility model also improves a light source system, which includes the above-mentioned color wheel, and also includes an excitation light source and a driving device. The regions and reflective regions are periodically exposed to excitation light, thereby emitting light of different wavelengths.

The above content is a further detailed description of the utility model in combination with specific implementation modes, and it cannot be determined that the specific implementation of the utility model is only limited to these descriptions. For a person of ordinary skill in the technical field to which the utility model belongs, without departing from the concept of the utility model, some simple deduction or substitutions can also be made, which should be regarded as belonging to the protection scope of the utility model.

Claims (10)

1. A reflection device, comprising a ceramic substrate (S3), characterized in that it also comprises a diffuse reflection glass layer (S1) located on a first surface of the ceramic substrate (S3), and the diffuse reflection glass layer (S1 ) includes a second surface away from the ceramic substrate (S3), and the ceramic substrate (S3) is a ceramic body with a dense structure; For the same incident light, the three-dimensional divergence angle of the reflected light formed by the first surface is smaller than the three-dimensional divergence angle of the reflected light formed by the second surface, wherein the three-dimensional divergence angle of a light beam is that the light intensity of the light beam is not less than The solid angle enclosed by the area of 50% of the light intensity at the center of the beam; The thickness of the diffuse reflection glass layer (S1) is between 0.04mm and 0.15mm. 2. The reflection device according to claim 1, characterized in that, the thickness of the diffuse reflection glass layer (S1) is between 0.08 mm and 0.12 mm. 3. The reflection device according to claim 1 or 2, characterized in that, the diffuse reflection glass layer is a diffuse reflection layer composed of white particles and glass. 4. The reflection device according to claim 1, characterized in that, the porosity of the ceramic substrate (S3) is less than or equal to 15%. 5. The reflection device according to claim 1, characterized in that the ceramic substrate (S3) is selected from alumina ceramic substrates, zirconia ceramic substrates, boron nitride ceramic substrates, composite ceramics of zirconia doped alumina One of the substrates. 6. The reflecting device according to claim 5, characterized in that, the ceramic substrate (S3) is a composite ceramic substrate of zirconia doped with alumina. 7. The reflection device according to any one of claims 4-6, characterized in that, the thickness of the ceramic substrate (S3) is greater than 0.5mm. 8. A wavelength conversion device, comprising a light-emitting layer and a reflective layer, wherein the reflective layer comprises the reflective device according to any one of claims 1 to 7, and the light-emitting layer is positioned at the diffuse reflection glass layer ( On the second surface of S1), the light-emitting layer is used to convert the light incident on the light-emitting layer into light of different wavelengths. 9. A color wheel, comprising a wavelength conversion region and a reflection region, wherein the reflection region comprises the reflection device according to any one of claims 1 to 7, the wavelength conversion region and the reflection region are within the color wheel The surfaces are stitched together to form a ring shape. 10. A light source system, comprising the color wheel as claimed in claim 9, further comprising an excitation light source and a driving device, the excitation light source is used to emit excitation light to irradiate on the color wheel, and the driving device is used for The color wheel is driven to rotate, so that the wavelength conversion area and the reflection area on the color wheel are periodically irradiated by excitation light.