Laser-driven light source lamp tube and sealing method thereof
By using multiple intermediary glass with gradient thermal expansion coefficients to seal step by step, the poor sealing effect caused by the difference in thermal expansion coefficient of quartz and fluoride window sheets is solved, and the effect of improving the transmittance of the LDLS ultraviolet band is achieved.
Patent Information
- Application Number
- CN202510223965.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-27
- Publication Date
- 2025-05-06
AI Technical Summary
In the prior art, the difference in thermal expansion coefficients of quartz and fluoride window sheets leads to poor sealing effect, resulting in a low transmittance in the ultraviolet band.
The intermediary glass with gradient thermal expansion coefficient is used to seal step by step. By introducing the intermediary glass between the quartz lamp tube and the fluoride window sheet, the thermal expansion stress is relieved, and the optical performance of the sealing area is ensured through the precisely controlled sealing process.
It effectively relieves the stress caused by the difference in thermal expansion coefficient, improves the stability and optical performance of the sealing area, and improves the overall transmittance of LDLS in the ultraviolet band.
Smart Images
Figure CN119934449A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of optical element sealing, and in particular to a laser driven light source lamp tube and a sealing method thereof. Background Art
[0002] In the Laser Driver Light Source (LDLS) system, quartz lamps and fluoride (such as magnesium fluoride MgF2) windows are important optical components. Quartz lamps have good optical properties and can emit light stably in the ultraviolet band. Magnesium fluoride (MgF2) windows have higher transmittance in the 0.11-7.5μm band, especially in the ultraviolet band. The transmittance at 0.2μm is greater than 85%, which plays a key role in improving the transmittance of LDLS in the ultraviolet band. However, the thermal expansion coefficients of quartz and fluoride windows are quite different. If the quartz lamp is directly combined with the fluoride window, when the temperature changes, deformation will occur due to the different thermal expansion coefficients, which will cause the seal between the two to burst or break, seriously affecting the stability and service life of the LDLS system, and limiting its performance in practical applications.
[0003] The industry has tried some solutions, such as combining mechanical fixation with sealants. However, sealants are prone to aging in the ultraviolet band and have poor optical properties, which cannot meet the needs of long-term stable optical transmission. There is also the use of a single intermediate layer material, but it is difficult to effectively match the thermal expansion differences between quartz and fluoride windows, resulting in poor sealing effects and low transmittance in the ultraviolet band.
[0004] Therefore, the prior art still needs to be improved and developed. Summary of the invention
[0005] The technical problem to be solved by the present invention is that, in view of the above-mentioned defects of the prior art, a laser driven light source lamp tube and a sealing method thereof are provided, aiming to solve the problem of low transmittance in the ultraviolet band caused by poor sealing effect of quartz and fluoride window pieces in the prior art.
[0006] The technical solution adopted by the present invention to solve the technical problem is as follows: A method for sealing a laser driven light source lamp tube, comprising the steps of: A quartz lamp, a window sheet and a plurality of intermediate glasses are provided; wherein the quartz lamp has a window; the thermal expansion coefficients of the intermediate glasses are different, the thermal expansion coefficients of the intermediate glasses are greater than the thermal expansion coefficient of the quartz lamp, and the thermal expansion coefficients of the intermediate glasses are less than the thermal expansion coefficients of the window sheets; the material of the window sheets is selected from at least one of magnesium fluoride, calcium fluoride and lithium fluoride; The window piece and all the intermediate glasses are melt-sealed in order of thermal expansion coefficient from large to small to obtain a combined body; The outermost intermediate glass in the assembly is melted and sealed to the window of the quartz lamp tube to obtain a laser driven light source lamp tube.
[0007] The sealing method of the laser driven light source lamp tube, wherein the window piece and all the intermediate glasses are melt-sealed in order of thermal expansion coefficient from large to small to obtain a combined body, specifically comprises: Fixed window piece; The intermediate glass with the largest thermal expansion coefficient is heated to a first preset temperature, so that the intermediate glass is melted and then dripped onto the sealing area on the surface of the window piece, and maintained at a first preset pressure for a first preset time, and then cooled to room temperature; In the order of thermal expansion coefficient from large to small, the intermediate glass of the next thermal expansion coefficient is heated to the first preset temperature, so that after the intermediate glass is melted, it drips onto the sealing area on the surface of the intermediate glass of the previous thermal expansion coefficient, and maintains the first preset pressure for the first preset time, and then cools to room temperature until all the intermediate glasses are melted and sealed to obtain a combination.
[0008] In the sealing method of the laser driven light source lamp tube, the width of the sealing area corresponding to each intermediate glass is less than 13 mm, and the thickness of each intermediate glass is 0.4 mm to 0.7 mm.
[0009] In the sealing method of the laser driven light source lamp tube, the first preset temperatures corresponding to the intermediate glasses are different.
[0010] The sealing method of the laser driven light source lamp tube, wherein the outermost intermediate glass in the assembly is melted and sealed to the window of the quartz lamp tube to obtain the laser driven light source lamp tube, specifically comprises: The outermost intermediate glass in the assembly is heated to a second preset temperature, the window of the quartz lamp tube is pressed against the sealing area on the surface of the intermediate glass, and the second preset pressure is maintained for a second preset time, and then cooled to room temperature to obtain a laser driven light source lamp tube.
[0011] The sealing method of the laser driven light source lamp tube, wherein the number of the intermediate glasses is 5.
[0012] The sealing method of the laser driven light source lamp tube is as follows: the window of the quartz lamp tube is circular, and the shape of the quartz lamp tube is spherical, cylindrical or olive-shaped.
[0013] The sealing method of the laser driven light source lamp tube, wherein the providing of a quartz lamp tube, a window sheet and a plurality of intermediate glasses specifically comprises: The quartz lamp tube, window piece and multiple intermediate glasses are cleaned with detergent and ultrasonic cleaning, and then placed in a dust-free environment to dry.
[0014] The sealing method of the laser driven light source lamp tube, wherein the outermost intermediate glass in the assembly is melt-sealed to the window of the quartz lamp tube to obtain the laser driven light source lamp tube, the sealing method further comprises: The flatness, fusion degree and stress distribution of the sealing area in the laser driven light source lamp tube are tested.
[0015] A laser driven light source lamp tube, wherein the lamp tube is obtained by using any of the sealing methods described above.
[0016] Beneficial effects: By using a variety of intermediate glasses with gradient thermal expansion coefficients for step-by-step sealing, the stress caused by the difference in thermal expansion coefficients between the quartz lamp and the fluoride window when the temperature changes is effectively alleviated, the optical performance of the sealing area is guaranteed, the light scattering and absorption caused by sealing is reduced, and the high transmittance characteristics of fluoride in the ultraviolet band are fully utilized, thereby improving the overall transmittance of LDLS in the ultraviolet band. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] Figure 1 It is a flow chart of a sealing method for a laser driven light source lamp tube in an embodiment of the present invention.
[0018] Figure 2 It is a first structural schematic diagram of a laser driven light source lamp tube in an embodiment of the present invention.
[0019] Figure 3 1 is a second structural schematic diagram of the laser driven light source lamp tube in an embodiment of the present invention.
[0020] Figure 4 Schematic diagram of the third structure of the laser driven light source lamp tube in the embodiment of the present invention.
[0021] Description of reference numerals: 1. Window piece; 2. Intermediate glass fusion body; 3. Electrode; 4. Quartz lamp tube. DETAILED DESCRIPTION
[0022] In order to make the purpose, technical solution and advantages of the present invention clearer and more specific, the present invention is further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.
[0023] like Figure 1 As shown, the present invention provides some embodiments of a sealing method for a laser driven light source lamp tube.
[0024] The sealing method of the laser driven light source lamp tube according to the embodiment of the present invention comprises the following steps: Step S100, providing a quartz lamp, a window sheet and a plurality of intermediate glasses; wherein the quartz lamp has a window; the thermal expansion coefficients of the intermediate glasses are different, the thermal expansion coefficients of the intermediate glasses are greater than the thermal expansion coefficient of the quartz lamp, and the thermal expansion coefficients of the intermediate glasses are less than the thermal expansion coefficients of the window sheets; the material of the window sheets is selected from at least one of magnesium fluoride, calcium fluoride and lithium fluoride; Step S200, melting and sealing the window sheet and all the intermediate glasses in order of thermal expansion coefficient from large to small to obtain a combined body; Step S300: Melt and seal the outermost intermediate glass in the assembly to the window of the quartz lamp tube to obtain a laser driven light source lamp tube.
[0025] Specifically, the laser-driven light source lamp tube adopts a quartz lamp tube, and the quartz lamp tube has a window, and the window is used to seal the intermediate glass and the window piece. The number of intermediate glasses and the thermal expansion coefficient are determined according to the specific application scenario. The material of the window piece is selected from at least one of magnesium fluoride, calcium fluoride, and lithium fluoride. Magnesium fluoride (MgF2) has high transmittance and good chemical stability in the ultraviolet band; the thermal expansion coefficient of calcium fluoride (CaF2) has a certain compatibility with some quartz materials and excellent optical properties; lithium fluoride (LiF) has unique optical properties in a specific ultraviolet region. These materials provide a variety of options for achieving good sealing and optical performance. The specific choice depends on the comprehensive requirements of the actual application for optical and thermal performance. At room temperature, the thermal expansion coefficient of magnesium fluoride (MgF2) is anisotropic, and the direction parallel to the c-axis is 13.7×10 -6 ℃ -1 , perpendicular to the c-axis direction is 8.48×10 -6 ℃ -1 , belongs to soft glass. At room temperature, the thermal expansion coefficient of quartz is 5.5×10 -7 ℃ -1 The thermal expansion coefficient of the intermediate glass is between the thermal expansion coefficient of the quartz lamp and the thermal expansion coefficient of the window, that is, the thermal expansion coefficient of the quartz lamp < the thermal expansion coefficient of the intermediate glass < the thermal expansion coefficient of the window. For example, 5.5×10 -7 ℃ -1 <Thermal expansion coefficient of intermediate glass<8.48×10 -6 ℃ -1For example, there can be 5 intermediate glasses, and the thermal expansion coefficients of the 5 intermediate glasses are different, namely A1, A2, A3, A4, and A5, and A1>A2>A3>A4>A5. A1 is close to the thermal expansion coefficient of the window piece, and A5 is close to the thermal expansion coefficient of the quartz lamp. When the thermal expansion coefficient of the quartz lamp and the thermal expansion coefficient of the window piece are different, the number and thermal expansion coefficient of the intermediate glasses are also different.
[0026] The window piece, intermediate glass and quartz lamp are melt-sealed according to the size of the thermal expansion coefficient. The intermediate glass with the largest thermal expansion coefficient is melt-sealed with the window piece, and then the intermediate glass with an adjacent thermal expansion coefficient is selected for sealing. The intermediate glass with a smaller thermal expansion coefficient is melt-sealed with the intermediate glass with a larger thermal expansion coefficient, until the intermediate glass with the smallest thermal expansion coefficient is melt-sealed to obtain a combination. Finally, the intermediate glass with the smallest thermal expansion coefficient in the combination is melt-sealed with the quartz lamp, thereby obtaining a laser driven light source lamp.
[0027] The window of the quartz lamp tube is circular, and the shape of the quartz lamp tube is spherical, cylindrical or olive-shaped. The quartz lamp tube can be regular or irregular in shape, and the regular shape can be spherical, cylindrical, olive-shaped, etc. The sealing method of the present application can be applied to quartz lamp tubes of various shapes.
[0028] Step S100 specifically includes: Step S110: Clean the quartz lamp tube, the window piece and the plurality of intermediate glasses with a detergent and ultrasonic cleaning, and place them in a dust-free environment to dry.
[0029] Specifically, before melting and sealing, the quartz lamp tube, window piece and intermediate glass need to be cleaned, specifically using a detergent for cleaning, and then using ultrasonic cleaning to remove surface impurities such as dust, oil, etc., and then placed in a dust-free environment to dry. Cleanliness can also be tested, and the next step will be performed when the cleanliness meets the requirements; if the cleanliness does not meet the requirements, it needs to be cleaned again until the cleanliness meets the requirements.
[0030] Step S200 specifically includes: Step S210, fixing the window piece; Step S220, heating the intermediate glass with the largest thermal expansion coefficient to a first preset temperature in descending order of thermal expansion coefficient, so that the intermediate glass is melted and drips onto the sealing area on the surface of the window piece, and maintains a first preset pressure for a first preset time, and then cools to room temperature; Step S230: Heat the next intermediate glass with a thermal expansion coefficient to a first preset temperature. After the intermediate glass melts, let it drip onto the sealing area on the surface of the previous intermediate glass with a thermal expansion coefficient, maintain the first preset pressure for the first preset time, and then cool it to room temperature until all the intermediate glasses are melted and sealed to obtain an assembly.
[0031] Specifically, use a sealing device for melting and sealing. First, fix the window piece to the sealing device, and then heat the intermediate glass with the largest thermal expansion coefficient (i.e., expansion coefficient A1) to the first preset temperature T1, so that the intermediate glass with the largest thermal expansion coefficient melts. The molten intermediate glass has rheological properties and can slowly drip onto the sealing area on the surface of the window piece. Then, continuously extrude the intermediate glass on the surface of the window piece, with the pressure magnitude being the first preset pressure P1 and the duration being the first preset time t1. Then, cool the window piece and the first layer of intermediate glass to room temperature. Arrange them in descending order of thermal expansion coefficient. Heat the next intermediate glass with a thermal expansion coefficient (i.e., expansion coefficient A2) to the first preset temperature T2, so that the next intermediate glass with a thermal expansion coefficient (i.e., expansion coefficient A2) melts. The molten intermediate glass slowly drips onto the sealing area on the surface of the previous intermediate glass with an expansion coefficient (i.e., expansion coefficient A1), and continuously extrude the intermediate glass, with the pressure magnitude being the first preset pressure P2 and the duration being the first preset time t2. Then, cool the window piece, the first layer of intermediate glass, and the second layer of intermediate glass to room temperature. There are 5 intermediate glasses. The intermediate glass with expansion coefficient A3 uses the first preset temperature T3, the first preset pressure P3, and the first preset time t3; the intermediate glass with expansion coefficient A4 uses the first preset temperature T4, the first preset pressure P4, and the first preset time t4; the intermediate glass with expansion coefficient A5 uses the first preset temperature T5, the first preset pressure P5, and the first preset time t5.
[0032] The first preset temperatures corresponding to the respective intermediate glasses are different. The first preset temperature T1 corresponding to the intermediate glass with expansion coefficient A1, the first preset temperature T2 corresponding to the intermediate glass with expansion coefficient A2, the first preset temperature T3 corresponding to the intermediate glass with expansion coefficient A3, the first preset temperature T4 corresponding to the intermediate glass with expansion coefficient A4, and the first preset temperature T5 corresponding to the intermediate glass with expansion coefficient A5 are all different. Specifically, T1 < T2 < T3 < T4 < T5. The first preset pressures corresponding to the respective intermediate glasses can be the same or not completely the same. The first preset times corresponding to the respective intermediate glasses can be the same or not completely the same.
[0033] The width of the sealing area corresponding to each intermediate glass is less than 13mm, and the thickness of each intermediate glass is 0.4mm~0.7mm. The sealing area corresponding to each intermediate glass should not be too large. When the width of the sealing area is less than 13mm, it is not easy to produce defects such as bubbles and cracks. The thickness of each intermediate glass is 0.4mm~0.7mm, which is conducive to the fusion between the intermediate glasses and forms a better flatness, thereby ensuring the compactness and stability of the sealing structure, and is conducive to forming a combination with a smoother expansion coefficient gradient.
[0034] Step S300 specifically includes: Step S310, heating the outermost intermediate glass in the assembly to a second preset temperature, pressing the window of the quartz lamp tube against the sealing area on the surface of the intermediate glass, maintaining the second preset pressure for a second preset time, and then cooling to room temperature to obtain a laser driven light source lamp tube.
[0035] Specifically, the outermost intermediate glass of the assembly is the intermediate glass with the smallest thermal expansion coefficient, and the intermediate glass is melt-sealed with the window of the quartz lamp. The intermediate glass is heated to a second preset temperature, and the window of the quartz lamp is pressed against the sealing area on the surface of the intermediate glass, and the second preset pressure is maintained for a second preset time, and then cooled to room temperature to obtain a laser-driven light source lamp. The process parameters such as temperature, pressure and time of each melt-sealing process need to be strictly controlled to ensure that the melt-sealing is firm and uniform, to avoid defects such as bubbles and cracks, to ensure that the optical properties of the sealing area are not affected, and to thereby improve the transmittance of the LDLS ultraviolet band.
[0036] After step S300, the sealing method further includes: Step S400: detecting the flatness, fusion degree and stress distribution of the sealing area in the laser driven light source tube.
[0037] Specifically, the sealing area of the laser-driven light source lamp tube is inspected, and the specific inspection indicators include: at least one of flatness, fusion and stress distribution. The higher the flatness of the sealing area, the higher the fusion, the less or more dispersed the stress distribution, the higher the quality of the laser-driven light source lamp tube.
[0038] The sealing method of the laser-driven light source lamp tube of the present application has the following technical effects: 1. By using a variety of intermediate glasses with gradient thermal expansion coefficients for step-by-step sealing, the stress generated by the quartz lamp tube and the fluoride window piece due to the difference in thermal expansion coefficients when the temperature changes is effectively alleviated, greatly reducing the risk of bursting or cracking in the sealing area, and improving the stability and service life of the assembly.
[0039] 2. The precisely controlled sealing process and reasonable selection of intermediate glass ensure the optical performance of the sealing area, reduce the light scattering and absorption caused by sealing, and give full play to the high transmittance characteristics of fluoride in the ultraviolet band, thereby improving the overall transmittance of LDLS in the ultraviolet band and enhancing its performance in related application fields.
[0040] Based on the sealing method of the laser-driven light source lamp tube described in any of the above embodiments, the present invention also provides a preferred embodiment of the laser-driven light source lamp tube: Please also see Figure 2-Figure 4 The present invention provides some embodiments of a laser driven light source lamp tube.
[0041] The laser driven light source lamp tube of the present invention is obtained by adopting the sealing method as described above.
[0042] In a preferred implementation of the embodiment of the present invention, Figure 2-Figure 4 As shown, the laser driven light source lamp tube includes: a quartz lamp tube 4 and an assembly; the quartz lamp tube 4 has a window; the assembly includes: a window piece 1 and an intermediate glass fusion body 2 with an expansion coefficient gradient, the side of the intermediate glass fusion body 2 with a larger thermal expansion coefficient is melt-sealed with the window piece 1, and the side of the intermediate glass fusion body 2 with a smaller thermal expansion coefficient is melt-sealed with the window; the material of the window piece 1 is selected from at least one of magnesium fluoride, calcium fluoride, and lithium fluoride, and the intermediate glass fusion body 2 is formed by melting and sealing a plurality of intermediate glasses with different thermal expansion coefficients in the order of the thermal expansion coefficients.
[0043] In a preferred implementation of the embodiment of the present invention, Figure 2-Figure 4 As shown, there are two electrodes 3 disposed in the quartz lamp tube 4. The window corresponds to the area between the two electrodes 3, and the window sheet 1 corresponds to the area between the two electrodes 3. When the area between the two electrodes 3 emits light, the light (especially ultraviolet light) penetrates the assembly from the window to the outside of the laser driven light source lamp tube.
[0044] In a preferred implementation of the embodiment of the present invention, Figure 2-Figure 4 As shown, the combination is cylindrical or spherical.
[0045] Specifically, the window piece 1 is located on the outside of the assembly. The thermal expansion coefficient of the window piece 1 is relatively large. When the laser drives the light source lamp to emit light, the temperature rises, and the window piece 1 and the intermediate glass close to the window piece 1 are more likely to expand and become larger in size. More ultraviolet light penetrates the window piece 1, and different intermediate glasses have different expansion degrees and different size changes. The molten sealing structure is more reliable, does not affect the optical performance of the sealing area, and achieves stable luminescence in the ultraviolet band.
[0046] It should be understood that the application of the present invention is not limited to the above examples. For ordinary technicians in this field, improvements or changes can be made based on the above description. All these improvements and changes should fall within the scope of protection of the claims attached to the present invention.
Claims
1. A method for sealing a laser driven light source tube, characterized in that: Includes steps: A quartz lamp, a window sheet and a plurality of intermediate glasses are provided; wherein the quartz lamp has a window; the thermal expansion coefficients of the intermediate glasses are different, the thermal expansion coefficients of the intermediate glasses are greater than the thermal expansion coefficient of the quartz lamp, and the thermal expansion coefficients of the intermediate glasses are less than the thermal expansion coefficients of the window sheets; the material of the window sheets is selected from at least one of magnesium fluoride, calcium fluoride and lithium fluoride; The window piece and all the intermediate glasses are melt-sealed in order of thermal expansion coefficient from large to small to obtain a combined body; The outermost intermediate glass in the assembly is melted and sealed to the window of the quartz lamp tube to obtain a laser driven light source lamp tube.
2. The sealing method of the laser driven light source lamp tube according to claim 1, characterized in that: The method comprises: sequentially melting and sealing the window sheet and all the intermediate glasses in the order of the thermal expansion coefficient from large to small to obtain a combined body; specifically, the method comprises: Fixed window piece; The intermediate glass with the largest thermal expansion coefficient is heated to a first preset temperature, so that the intermediate glass is melted and then dripped onto the sealing area on the surface of the window piece, and maintained at a first preset pressure for a first preset time, and then cooled to room temperature; In the order of thermal expansion coefficient from large to small, the intermediate glass of the next thermal expansion coefficient is heated to the first preset temperature, so that after the intermediate glass is melted, it drips onto the sealing area on the surface of the intermediate glass of the previous thermal expansion coefficient, and maintains the first preset pressure for the first preset time, and then cools to room temperature until all the intermediate glasses are melted and sealed to obtain a combination.
3. The sealing method of the laser driven light source lamp tube according to claim 2, characterized in that: The width of the sealing area corresponding to each intermediate glass is less than 13 mm, and the thickness of each intermediate glass is 0.4 mm to 0.7 mm.
4. The sealing method of the laser driven light source lamp tube according to claim 2, characterized in that: The first preset temperatures corresponding to the intermediate glasses are different.
5. The sealing method of the laser driven light source lamp tube according to claim 1, characterized in that: The outermost intermediate glass in the assembly is melted and sealed to the window of the quartz lamp tube to obtain a laser driven light source lamp tube, which specifically includes: The outermost intermediate glass in the assembly is heated to a second preset temperature, the window of the quartz lamp tube is pressed against the sealing area on the surface of the intermediate glass, and the second preset pressure is maintained for a second preset time, and then cooled to room temperature to obtain a laser driven light source lamp tube.
6. The sealing method of the laser driven light source lamp tube according to claim 1, characterized in that: There are five intermediate glasses.
7. The sealing method of a laser driven light source lamp tube according to any one of claims 1 to 6, characterized in that: The window of the quartz lamp tube is circular, and the shape of the quartz lamp tube is spherical, cylindrical or olive-shaped.
8. The sealing method of a laser driven light source lamp tube according to any one of claims 1 to 6, characterized in that: The provision of a quartz lamp tube, a window sheet, and a plurality of intermediate glasses specifically includes: The quartz lamp tube, window piece and multiple intermediate glasses are cleaned with detergent and ultrasonic cleaning, and then placed in a dust-free environment to dry.
9. The sealing method of a laser driven light source lamp tube according to any one of claims 1 to 6, characterized in that: After the outermost intermediate glass in the assembly is melt-sealed to the window of the quartz lamp tube to obtain the laser driven light source lamp tube, the sealing method further comprises: The flatness, fusion degree and stress distribution of the sealing area in the laser driven light source lamp tube are tested.
10. A laser driven light source lamp tube, characterized in that: The method is obtained by using the sealing method as described in any one of claims 1 to 9.