Fluorescence wavelength converter and manufacturing method thereof

Abstract

The invention discloses a fluorescence wavelength converter and a manufacturing method thereof, and is characterized in that the fluorescence wavelength converter sequentially comprises a substrate for bearing the fluorescence wavelength converter, a reflecting film, a fluorescent film for converting monochromatic incident light into white light, and an antireflection film. The manufacturing method of the fluorescence wavelength converter comprises the following steps: preparing the substrate, plating the reflecting film on one surface of the substrate, sintering the fluorescent film on the reflecting film at high temperature, and plating the antireflection film on the upper surface of the fluorescent film. The fluorescence wavelength converter can be applied to wavelength conversion of laser excitation fluorescence, and has the advantages of high conversion efficiency, stable optical performance, strong environmental corrosion resistance, good heat-conducting property, low cost and the like.

Description

Technical Field

[0001] This invention relates to a fluorescence wavelength converter and its manufacturing method, which is applied to the wavelength conversion of laser-excited fluorescence and has the advantages of high conversion efficiency, good thermal conductivity, stable optical performance, and low cost. Background Technology

[0002] In white laser technology based on laser-induced fluorescence, monochromatic laser light emitted by a laser diode is converted into white light by a fluorescence wavelength converter, hence the name white laser. Due to its extremely high brightness, extremely small emitting surface, and excellent reliability, white laser light sources have found increasing applications in numerous fields, including digital projection, automotive headlights, remote search, medical devices, and machine vision.

[0003] A fluorescence wavelength converter receives high-energy monochromatic laser light during operation and converts it into broad-spectrum white light. Since approximately 20% of the incident light energy inevitably becomes heat during this process, if this heat cannot be dissipated into the environment in a timely manner, it will severely affect the efficiency and reliability of the fluorescence wavelength converter. Therefore, good thermal conductivity is crucial for the overall efficiency and reliability of the white laser source.

[0004] like Figure 1 As shown, current reflective fluorescence wavelength converters typically have a layer of fluorescent material (102) coated on a thermally conductive substrate (101). The heat generated by the fluorescence wavelength converter during operation is dissipated to the environment through the thermally conductive substrate (101) to ensure that the fluorescence wavelength converter is kept at a relatively low temperature. Therefore, the heat dissipation performance of the fluorescence wavelength converter largely depends on the thermal conductivity of the thermally conductive substrate (101). An ideal thermally conductive substrate should have the following characteristics: (1) excellent thermal conductivity; (2) a coefficient of thermal expansion that matches the fluorescent material; (3) excellent surface flatness and reflectivity; (4) good mechanical properties; and (5) low material cost.

[0005] To ensure the heat dissipation performance of fluorescence wavelength converters, a common approach is to use a metal substrate. The high thermal conductivity of the metal rapidly conducts the heat generated by the fluorescent layer during operation to a heat sink and then dissipates it into the surrounding environment. However, due to the significant difference in thermal expansion coefficients between the metal substrate and the fluorescent film, substantial residual stress develops at the interface between them during manufacturing and subsequent use. This stress severely impacts the structural reliability of the fluorescent film and the thermal conductivity of the fluorescence wavelength converter. Therefore, it is necessary to select more suitable substrate materials and manufacturing methods that integrate the substrate and fluorescent layer to obtain highly efficient and reliable fluorescence wavelength converters. Summary of the Invention

[0006] This invention patent is a fluorescence wavelength converter and its manufacturing method. One aspect of it is a fluorescence wavelength converter, characterized in that it sequentially includes: a substrate carrying the fluorescence wavelength converter, a reflective film, a fluorescent film that converts monochromatic incident light into white light, and an antireflection film.

[0007] Furthermore, the substrate is one or a combination of the following materials: monocrystalline silicon, polycrystalline silicon, silicon carbide, with a thickness between 0.3 mm and 2.0 mm and a surface roughness of less than 100 nm.

[0008] Furthermore, the thickness of the fluorescent film is between 0.01 mm and 0.1 mm, and the selected phosphor is one or a combination of several of the following materials in different proportions: (Y,Tb)₂Al₅O₃ 12 :Ce 3+ (Sr,Ba,Ca)2Si5N8:Eu 2+ CaAlSiN3:Eu 2+ ,BaMgAl 10 O 17 Eu 2+ ,BaMgAl 10 O 17 Eu 2+ ,Mn 2+ Ca-alpha-SiAlON:Eu 2+ Beta-SiAlON:Eu 2+ (Ca,Sr,Ba)2P2O7:Eu 2+ (Ca,Sr,Ba)2P2O7:Eu 2+ ,Mn 2+ (Ca,Sr,Ba)5(PO4)3Cl:Eu 2+ Lu2SiO5:Ce 3+ (Ca,Sr,Ba)3SiO5:Eu 2+ (Ca,Sr,Ba)2SiO4:Eu 2+ Zn2SiO4:Mn 2+ BaAl 12 O 19 :Mn 2+ ,BaMgAl 14 O 23 :Mn 2 + SrAl 12 O 19 :Mn 2+ ,CaAl 12 O 19 :Mn 2+ YBO3:Tb 3+ LuBO3:Tb3+ Y2O3:Eu 3+ Y2SiO5:Eu 3+ Y3Al5O 12 Eu 3 + YBO3:Eu 3+ Y 0.65 Gd 0.35 BO3:Eu 3+ GdBO3:Eu 3+ YVO4:Eu 3+ .

[0009] Furthermore, the reflective film is composed of one or more of the following materials: SiO2, TiO2, Ta2O5, Al2O3, ZnO2, SnO2, ZrO2, AlN, and TiN, with a thickness between 0.01 and 0.2 mm.

[0010] Furthermore, the antireflective membrane is composed of one or more of the following materials: SiO2, MgF2, TiO2, Al2O3, ZnO, and CaF2, with a thickness between 0.01 and 0.2 mm.

[0011] Another aspect of this invention patent is a method for manufacturing a fluorescence wavelength converter, characterized by comprising preparing a substrate, depositing a reflective film on one side of the substrate, sintering a fluorescent film on the reflective film at high temperature, and depositing an antireflection film on the upper surface of the fluorescent film.

[0012] Furthermore, the reflective film is prepared using one or more of the following techniques in combination: chemical vapor deposition (CVD), atomic layer deposition (ALD), magnetron sputtering, electron beam evaporation, and thermal evaporation.

[0013] Furthermore, the preparation of fluorescent film slurry includes selecting the types of solvents and additives, as well as controlling their ratio with phosphors.

[0014] Furthermore, the fluorescent film can be coated or sprayed onto the reflective film.

[0015] Furthermore, the high-temperature sintering fluorescent film is sintered in air or a protective atmosphere at a temperature controlled between 300℃ and 600℃, and held at this temperature for 10-100 minutes.

[0016] Furthermore, the antireflective film is prepared using one or more of the following techniques in combination: chemical vapor deposition (CVD), atomic layer deposition (ALD), magnetron sputtering, electron beam evaporation, and thermal evaporation.

[0017] The present invention has the following advantages:

[0018] (1) Good heat dissipation performance: Si or SiC with high thermal conductivity is selected as the substrate material, which makes the fluorescence wavelength converter have excellent heat dissipation performance; (2) High reliability: Si or SiC has a similar coefficient of thermal expansion to the reflective film, fluorescent material and antireflective film, which reduces the residual stress generated by the structure of the fluorescence wavelength converter during sintering and actual use; (3) High conversion efficiency: The high flatness of the substrate and the high reflectivity of the reflective film work together to improve the light output efficiency of the fluorescence wavelength converter. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of a common reflective fluorescence wavelength converter.

[0020] Figure 2 This is a schematic diagram of the structure of a fluorescence wavelength converter.

[0021] Figure 3 This is a stress distribution diagram of a fluorescence wavelength converter when the thermal expansion difference is too large.

[0022] Figure 4 This is a schematic diagram of the manufacturing process for a fluorescence wavelength converter.

[0023] Figure 5 The emission spectrum of the YAG-Ce-based phosphor is shown.

[0024] Figure 6 This is a schematic diagram of the test light source structure.

[0025] Figure 7 The photoluminescence spectrum of a single-crystal silicon substrate fluorescence wavelength converter and a blue laser diode light source.

[0026] Figure 8 The graph shows the relationship between luminous flux and power for fluorescent wavelength converters on single-crystal silicon and aluminum substrates. Detailed Implementation

[0027] The fluorescence wavelength converter structure described in this invention patent is as follows: Figure 2 As shown, blue laser light enters the fluorescent film (203) through the antireflection film (204) of the fluorescent wavelength converter. A portion of the blue light is absorbed by the fluorescent film and converted into white light with a wavelength between 480-700nm. This white light, along with the unabsorbed blue light, is reflected by the reflective film (202) located on the substrate (201) and output again through the antireflection film (201).

[0028] One of the core aspects of this invention is the selection of a material with excellent thermal conductivity and a coefficient of thermal expansion similar to that of the fluorescent film and reflective film as the substrate for the fluorescence wavelength converter, thereby ensuring that the fluorescence wavelength converter has good thermal conductivity and structural reliability. In the manufacturing process of the fluorescence wavelength converter, high-temperature sintering is an essential step to ensure the interfacial bonding between the fluorescent film and the substrate; however, there are relative differences in thermal expansion between different materials. The greater this difference, the greater the residual stress generated during cooling, and the easier it is to damage the interface between the materials.

[0029] Generally, for a system composed of two materials with different coefficients of thermal expansion, residual stress will be generated within both materials when the system is cooled from a high temperature to a low temperature. Specifically, for a binary system such as a thin film-substrate, the relationship between the internal stress of the thin film and the change in ambient temperature can be expressed as follows: σ f =E f ε f =E f (α f -α s )ΔT#(1)

[0030] Where, σ f E represents the internal stress in the thin film. f α is the elastic modulus of the thin film. f α is the coefficient of thermal expansion of the thin film. s Let be the coefficient of thermal expansion of the substrate, and ΔT be the difference between the initial and final temperatures. Stress σ f When the value is positive, it is tensile stress; when the value is negative, it is compressive stress. From formula (1), it can be seen that the stress in the thin film is proportional to the difference in thermal expansion coefficients between the thin film and the substrate. The greater the difference in thermal expansion coefficients, the greater the residual thermal stress and the worse the stability of the thin film. The greater the temperature change in the environment, the greater the residual stress inside the thin film. Furthermore, the characteristics of the internal stress of the thin film are also related to the magnitude of the thermal expansion coefficients between the two: because ΔT < 0 during the cooling process, when the thermal expansion coefficient of the thin film is less than that of the substrate, according to formula (1), σ can be obtained. f <0 indicates that there is tensile stress inside the film; conversely, the film is subjected to compressive stress.

[0031] Taking YAG-Ce as a fluorescent film material as an example, its coefficient of thermal expansion is 8×10⁻⁶. -6 K -1 When different thermal expansion coefficients are used as substrates, the residual stress inside the fluorescent film can be estimated according to formula (1) when the temperature drops from 300℃ to 25℃. The results are listed in Table 1.

[0032] Table 1

[0033] Substrate material <![CDATA[Coefficient of thermal expansion / K -1 > Residual stress of fluorescent film / MPa Al <![CDATA[23.0×10 -6 ]]> 144 Cu <![CDATA[16.5×10 -6 ]]> 82 Si <![CDATA[2.6×10 -6 ]]> -52 SiC <![CDATA[4.0×10 -6 ]]> -38

[0034] As shown in Table 1, the fluorescent film experiences the highest tensile stress, reaching 144 MPa, when Al is used as the substrate material. This exceeds the tensile strength of the fluorescent film itself, and therefore, it may fracture upon cooling. This result can also be verified by... Figure 3 Let's demonstrate. When using Si and SiC as substrates, the fluorescent film is subjected to compressive stress during cooling, making it less prone to damage. Therefore, choosing Si and SiC as substrates ensures that the fluorescent film of the fluorescence wavelength converter will not be damaged by residual stress generated during cooling during manufacturing.

[0035] Besides the coefficient of thermal expansion, the thermal conductivity of the substrate supporting the fluorescent film is also an important factor in ensuring the excellent thermal conductivity of the fluorescent wavelength converter. Table 2 lists the thermal conductivity of several substrate materials. As can be seen from Table 2, the thermal conductivity of Si and SiC is on the same order of magnitude as that of Al, Cu, and other materials, and is an order of magnitude higher than that of sapphire.

[0036] Table 2

[0037] Substrate material <![CDATA[Thermal conductivity / W·m -1 ·K -1 > Al 205 Cu 385 Si 150 SiC 120 sapphire 30

[0038] The thickness and unevenness of the substrate supporting the fluorescent film are also important technical requirements. To facilitate heat transfer from the fluorescent film to the heat sink in contact with the substrate, the substrate thickness needs to be as thin as possible. However, the fluorescence wavelength converter itself requires a certain level of mechanical strength. Therefore, in this invention, a substrate thickness between 0.3 mm and 2.0 mm is selected. To further improve the efficiency of the substrate in converting the fluorescent film, a high-reflectivity optical film needs to be formed on the substrate; therefore, the substrate needs to have considerable flatness. In this invention, the surface unevenness of the substrate is required to be less than 100 nm.

[0039] The reflective film must not only ensure excellent reflectivity in the visible light band together with the substrate, but also promote a tight bond between the fluorescent film and the substrate during sintering. Therefore, it needs to meet the following basic requirements: (1) the coefficient of thermal expansion should be well matched with that of the substrate and the fluorescent film; (2) it should have good interfacial bonding force (adhesion) with the substrate and the fluorescent film; (3) it should improve the reflectivity of the substrate's reflective surface; (4) the thickness should be as thin as possible to reduce thermal resistance; and (5) the film-making process should be simple and controllable. Considering all these factors, this invention proposes that the reflective film is composed of one or more of the following thin films: SiO2, TiO2, Ta2O5, Al2O3, ZnO2, SnO2, ZrO2, AlN, and TiN, with a thickness between 0.01 mm and 0.2 mm.

[0040] The fluorescent film above the reflective film is crucial for the wavelength converter to achieve wavelength conversion. It needs to meet the following conditions: (1) excellent fluorescence wavelength conversion efficiency; (2) good thermal conductivity; (3) good heat resistance; (4) certain mechanical strength; (5) absorb incident light and convert it into the actual fluorescence type output by the fluorescence wavelength converter, such as one or a combination of green, yellow, red, orange, etc. To meet these conditions, the phosphor can be composed of one or more of the following materials in different proportions: (Y,Tb)2Al5O 12 :Ce 3+ (Sr,Ba,Ca)2Si5N8:Eu 2+ CaAlSiN3:Eu 2+ ,BaMgAl 10 O 17 Eu 2+ ,BaMgAl 10 O 17 Eu 2+ ,Mn 2+ Ca-alpha-SiAlON:Eu 2+ Beta-SiAlON:Eu 2+ (Ca,Sr,Ba)2P2O7:Eu 2+ (Ca,Sr,Ba)2P2O7:Eu 2+ ,Mn 2+ (Ca,Sr,Ba)5(PO4)3Cl:Eu 2 + Lu2SiO5:Ce 3+ (Ca,Sr,Ba)3SiO5:Eu 2+ (Ca,Sr,Ba)2SiO4:Eu 2+ Zn2SiO4:Mn 2+ BaAl 12 O 19 :Mn 2+ ,BaMgAl 14 O 23 :Mn 2+ SrAl 12 O 19 :Mn 2+ ,CaAl 12 O 19 :Mn 2+ YBO3:Tb 3+ LuBO3:Tb 3+ Y2O3:Eu 3+ Y2SiO5:Eu 3+ Y3Al5O 12 Eu3+ YBO3:Eu 3+ Y 0.65 Gd 0.35 BO3:Eu 3+ GdBO3:Eu 3+ YVO4:Eu 3+ .

[0041] The outermost antireflective coating must not only isolate the fluorescent film from the external environment to improve its stability under various conditions, but also have high transmittance to ensure the luminous efficiency of the fluorescent wavelength converter. In addition, since the coating process is after the fluorescent film is sintered, the coating temperature should not exceed the sintering temperature of the fluorescent film to prevent damage to the bond between the fluorescent film and the reflective film. In general, the antireflective coating needs to meet the following basic requirements: (1) the coefficient of thermal expansion should be well matched with the substrate, reflective film and fluorescent film; (2) it should have good interfacial bonding force (adhesion) with the fluorescent film; (3) it should have high transmittance and not reduce the overall luminous efficiency of the fluorescent wavelength converter; (4) it should be as thin as possible to reduce thermal resistance; (5) the film-making process should be simple and controllable, and the coating temperature should not exceed the sintering temperature of the fluorescent film. Taking all these considerations into account, the present invention proposes that the antireflection membrane be composed of one or more of the following material films: SiO2, MgF2, TiO2, Al2O3, ZnO, CaF2, and the thickness of the antireflection membrane is between 0.01mm and 0.2mm.

[0042] After determining the material types and dimensional parameters of all components, another key aspect of this invention is the manufacturing process. The process flow of this invention is as follows: Figure 4 As shown, the process includes: preparing a substrate, depositing a reflective film on one side of the substrate, sintering a fluorescent film on the reflective film at high temperature, and depositing an antireflective film on the upper surface of the fluorescent film.

[0043] To improve the bonding effect between the reflective film and the substrate and increase the reflectivity, the reflective film is coated using techniques such as chemical vapor deposition (CVD), atomic layer deposition (ALD), magnetron sputtering, electron beam evaporation, and thermal evaporation.

[0044] To ensure good interfacial adhesion when forming a fluorescent film on the reflective film, this invention employs coating printing or spraying techniques to uniformly prepare the slurry on the reflective film. To adjust the viscosity of the fluorescent film slurry and facilitate uniform coating, additives and deionized water are added during slurry preparation. This invention proposes using one or more of the following materials as additives: SiO2, Al2O3, P2O5, B2O3, and Na2O. These additives, in addition to working with deionized water to adjust the slurry viscosity, also contribute to a certain degree of porosity and good heat resistance after the fluorescent film is sintered.

[0045] The high-temperature sintering of the fluorescent film is carried out in air or a protective atmosphere, without the need for a special atmosphere, which is convenient for preparation. The sintering temperature is controlled between 300℃ and 600℃, and the film is held at this temperature for 10-100 minutes.

[0046] In order to add a protective film to the fluorescent layer while ensuring the transmittance of the incident laser, the antireflection film is coated using techniques such as chemical vapor deposition (CVD), atomic layer deposition (ALD), magnetron sputtering, electron beam evaporation, and thermal evaporation.

[0047] The embodiments of the present invention will be described in detail below with reference to the accompanying drawings and implementation methods, but the present invention is not limited to these embodiments.

[0048] Example 1: Fabrication of a fluorescence wavelength converter on a single-crystal silicon substrate

[0049] The structure of the single-crystal silicon substrate fluorescence wavelength converter described in this embodiment is similar to... Figure 2 The process is the same. First, the single-crystal silicon substrate (201) is polished on one side, and a reflective film (202) is deposited on the polished side. The other side serves as the contact surface between the fluorescence wavelength converter and the heat sink. A fluorescence film (203) is then coated and sintered on the reflective film (202). The reflective film (202) serves two purposes: firstly, it increases the reflectivity of the laser-receiving side of the single-crystal silicon substrate (201) to ensure that the output brightness after conversion by the fluorescence film (203) is as high as possible; secondly, it acts as a buffer layer, utilizing its thermal expansion coefficient to be between that of the fluorescence film (203) and the single-crystal silicon substrate (201), reducing the residual stress generated during the high-temperature sintering process and improving the bonding effect of the fluorescence wavelength converter. After sintering, an antireflective film (204) is deposited on the upper surface of the fluorescence film (203) to isolate it from the environment, thereby further improving the stability of the fluorescence layer under various environments while maintaining high surface transmittance and not affecting the light output efficiency.

[0050] according to Figure 4 The process flow diagram shows that, firstly, to ensure sufficient reflectivity and flatness of the fluorescence wavelength converter, a 0.3mm single-crystal silicon wafer is selected as the substrate. To ensure the adhesion between the fluorescence film and the single-crystal silicon substrate, and to improve the reflectivity of the single-crystal silicon substrate in the 400-700nm wavelength range to over 95%, a reflective film is first deposited on the polished surface of the single-crystal silicon substrate. In this embodiment, SiO2 / Ta2O5 is selected as the reflective film, and it is deposited onto the polished surface of the single-crystal silicon substrate using electron beam evaporation technology.

[0051] In this embodiment, a YAG-Ce-based phosphor was selected, and its emission spectrum is shown below. Figure 5As shown, it is mixed with additives in a 4:1 ratio, wherein the additives contain SiO2 and Na2O in a 20:9 ratio, and then 9% of the total mass of deionized water is added. After stirring thoroughly for 40 seconds, a fluorescent film slurry is prepared for later use.

[0052] The phosphor film slurry was uniformly coated onto the surface of the reflective film using a coating method. After the coating was air-dried for 30 minutes, the single-crystal silicon substrate was placed in a high-temperature sintering furnace. The temperature was increased to 300°C at a heating rate of 5°C / min and held for 60 minutes. After holding, the substrate was cooled with the furnace until it was completely cooled, thus completing the sintering of the phosphor film.

[0053] In this embodiment, SiO2 / MgF2 is selected as the antireflection film, and it is deposited onto the surface of the fluorescent film using electron beam evaporation technology.

[0054] Example 2: Optical performance of a fluorescence wavelength converter on a single-crystal silicon substrate

[0055] A light source was fabricated by combining the fluorescent wavelength converter manufactured in Example 1 with a laser diode, and its optical performance was tested. The optical path structure used for testing is as follows: Figure 6 As shown, (601) is a laser diode, (602) is an optical shaping system composed of two convex lenses, and (603) is a fluorescence wavelength converter.

[0056] The test results of the laser-excited fluorescence wavelength converter under different driving currents are shown in Table 3. The emission spectrum of the system at a driving current of 2A is shown in Table 3. Figure 7 As shown.

[0057] Table 3

[0058] Current / A Luminous flux / lm Excitation source wavelength / nm Color temperature / K 1.0 146 452 6500 1.5 230 452 6600 2.0 367 452 6670 2.5 443 452 6790 3.0 511 452 6800

[0059] Example 3: Environmental stability of a single-crystal silicon substrate fluorescence wavelength converter

[0060] Twelve fluorescence wavelength converters manufactured in Example 1 were taken and divided into three groups. These converters were placed in environments with humidity levels of 30%, 50%, and 80%, respectively, and subjected to constant humidity treatment for 24 hours. Afterward, they were removed and used as follows: Figure 6 The light source structure shown was tested for optical performance under a driving current of 3A. The test results of the average luminous flux and color temperature of each group of samples are listed in Table 4.

[0061] Table 4

[0062] humidity Luminous flux / lm Excitation source wavelength / nm Color temperature / K 30％ 508 452 6800 50％ 513 452 6700 80％ 509 452 6800

[0063] While keeping other materials unchanged in Example 1, 1060 aluminum was used instead of single-crystal silicon as the substrate material to manufacture the fluorescence wavelength converter. Twelve such fluorescence wavelength converters were taken and divided into three groups, placed in environments with humidity levels of 30%, 50%, and 80%, respectively. After 24 hours of constant humidity treatment, they were removed and processed using... Figure 6 The white laser light source structure shown was tested for optical performance under a driving current of 3A. The test results of the average luminous flux and color temperature of each group are listed in Table 5.

[0064] Table 5

[0065] humidity Luminous flux / lm Excitation source wavelength / nm Color temperature / K 30％ 508 452 6800 50％ 497 452 7000 80％ 436 452 8300

[0066] Comparing the data in Tables 4 and 5, it can be seen that for the fluorescence wavelength converter using single-crystal silicon as the substrate, the maximum difference in luminous flux and color temperature between samples stored under different humidity environments is 1.0% and 1.3%, respectively, both within the range of instrument error measurement. However, for the fluorescence wavelength converter using 1060 aluminum as the substrate, the luminous flux decreases and the color temperature increases with increasing humidity. When the humidity reaches 80%, the luminous flux decreases by 14.2% and the color temperature increases by 22.2%, indicating that its optical performance has been affected. This example demonstrates that the fluorescence wavelength converter proposed in this invention has superior environmental stability compared to commonly used fluorescence wavelength converters with metal substrates.

[0067] Example 4: Thermal stability of a single-crystal silicon substrate fluorescence wavelength converter

[0068] Using the fluorescence wavelength converter manufactured in Example 1, it is combined as follows Figure 6 The white laser light source structure shown was operated continuously for 30 minutes at its rated current of 2A, and its optical performance was tested every 5 minutes. Its luminous flux and color temperature are shown in Table 5.

[0069] Table 5

[0070] Time / min Luminous flux / lm Excitation source wavelength / nm Color temperature / K 0 372 452 6680 5 365 452 6710 10 363 452 6730 15 361 452 6690 20 364 452 6750 25 363 452 6690 30 361 452 6730

[0071] According to the data in Table 5, the luminous flux of the light source reached its peak during the first optical performance test. As the operating time increased, the temperature of the laser tube and the fluorescence wavelength converter rose slightly, but quickly stabilized. The luminous flux basically stabilized after 5 minutes. Therefore, the fluorescence wavelength converter of this invention exhibits good thermal stability during use.

[0072] Example 5: Heat dissipation performance of a single-crystal silicon substrate fluorescence wavelength converter

[0073] Using the fluorescence wavelength converter manufactured in Example 1, it is combined as follows Figure 6The white laser source structure shown was lit at 0.5A, 1.0A, 1.5A, 2.0A, 2.5A, and 3.0A respectively, and its luminous flux and power were recorded.

[0074] As a control group, the aluminum substrate fluorescence wavelength converter described in Example 3 was used. It was lit at 0.5A, 1.0A, 1.5A, 2.0A, 2.5A, and 3.0A, and its luminous flux and power were recorded. The relationship between the luminous flux and power of the two fluorescence wavelength converters was compared with... Figure 8 .from Figure 8 As can be seen, the slope of the luminous flux versus power curve of the fluorescence wavelength converter with crystalline silicon as the substrate is very close to that of the aluminum substrate, thus indicating that the fluorescence wavelength converter with single-crystal silicon substrate has similar heat dissipation performance to that of the fluorescence wavelength converter with aluminum substrate.

[0075] Those skilled in the art should understand that the embodiments of the present invention described above and shown in the accompanying drawings are merely examples and do not limit the scope of the present invention. The purpose of the present invention has been fully and effectively achieved. The functions and structural principles of the present invention have been shown and explained in the embodiments, and any variations or modifications may be made to the implementation of the present invention without departing from the stated principles.

Claims

1. A fluorescence wavelength converter, characterized in that, In order, they include: Substrate supporting a fluorescence wavelength converter, reflective film, fluorescent film that converts monochromatic incident light into white light, and antireflective film.

2. A fluorescence wavelength converter according to claim 1, characterized in that, The substrate is one or more of the following materials: monocrystalline silicon, monocrystalline silicon, silicon carbide.

3. A fluorescence wavelength converter according to claim 1, characterized in that, The substrate has a thickness of 0.3mm-2.0mm and a surface roughness of less than 100nm.

4. A fluorescence wavelength converter according to claim 1, characterized in that, The reflective film is one or more of the following materials: SiO2, TiO2, Ta2O5, Al2O3, ZnO, SnO2, ZrO2, AlN, TiN.

5. A fluorescence wavelength converter according to claim 1, characterized in that, The fluorescent film is one or more of the following materials: (Y,Tb)₂Al₅O 12 :Ce 3+ (Sr,Ba,Ca)2Si5N8:Eu 2+ CaAlSiN3:Eu 2+ ,BaMgAl 10 O 17 Eu 2+ ,BaMgAl 10 O 17 Eu 2+ ,Mn 2+ Ca-alpha-SiAlON:Eu 2+ Beta-SiAlON:Eu 2+ (Ca,Sr,Ba)2P2O7:Eu 2+ (Ca,Sr,Ba)2P2O7:Eu 2+ ,Mn 2+ (Ca,Sr,Ba)5(PO4)3Cl:Eu 2+ Lu2SiO5:Ce 3+ (Ca,Sr,Ba)3SiO5:Eu 2+ (Ca,Sr,Ba)2SiO4:Eu 2+ Zn2SiO4:Mn 2+ BaAl 12 O 19 :Mn 2+ ,BaMgAl 14 O 23 :Mn 2 + SrAl 12 O 19 :Mn 2+ ,CaAl 12 O 19 :Mn 2+ YBO3:Tb 3+ LuBO3:Tb 3+ Y2O3:Eu 3+ Y2SiO5:Eu 3+ Y3Al5O 12 Eu 3 + YBO3:Eu 3+ Y 0.65 Gd 0.35 BO3:Eu 3+ GdBO3:Eu 3+ YVO4:Eu 3+ .

6. A fluorescence wavelength converter according to claim 1, characterized in that, The thickness of the fluorescent film is 0.01mm-0.1mm.

7. A fluorescence wavelength converter according to claim 1, characterized in that, The antireflective membrane is one or more of the following materials: SiO2, MgF2, TiO2, Al2O3, ZnO, and CaF2.

8. A method for manufacturing a fluorescence wavelength converter, used to manufacture a fluorescence wavelength converter as described in any one of claims 1-7, characterized in that, The process includes the following steps: preparing a substrate, depositing a reflective film on one side of the substrate, sintering a fluorescent film on the reflective film at high temperature, and depositing an antireflective film on the upper surface of the fluorescent film.

9. A method for manufacturing a fluorescence wavelength converter according to claim 8, characterized in that, The reflective coating on one side of the substrate employs one or more of the following techniques in combination: chemical vapor deposition (CVD), atomic layer deposition (ALD), magnetron sputtering, electron beam evaporation, and thermal evaporation.

10. A method for manufacturing a fluorescence wavelength converter according to claim 8, characterized in that, The high-temperature sintering of the fluorescent film on the reflective film is carried out under the following process conditions: the fluorescent film is coated or sprayed onto the reflective film, the sintering atmosphere is set to one of air, nitrogen or argon, the atmosphere pressure is one atmosphere of normal pressure, the sintering temperature is between 300℃ and 600℃, and the holding time is between 10 minutes and 100 minutes.

11. A method for manufacturing a fluorescence wavelength converter according to claim 8, characterized in that, The antireflection coating deposited on the upper surface of the fluorescent film is achieved using one or more of the following techniques: chemical vapor deposition (CVD), atomic layer deposition (ALD), magnetron sputtering, electron beam evaporation, and thermal evaporation.

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