Precise temperature control device for ultraviolet laser in harsh environment

Abstract

The utility model relates to a kind of for under harsh environment ultraviolet laser precision temperature control device, including shell, shell is equipped with cavity;Cavity is equipped with substrate A and substrate B respectively, substrate A is equipped with pump light source, substrate B is equipped with optical element, and optical element includes at least one frequency doubling crystal;Heating film and temperature sensor A are respectively equipped on the outer wall of shell, and shell lower end is equipped with at least one TEC refrigerating sheet A;TEC refrigerating sheet B and temperature sensor B are respectively equipped on substrate A;The position of substrate B is equipped with TEC refrigerating sheet C corresponding to the position of frequency doubling crystal, and temperature sensor C is equipped on substrate B;Heating film, TEC refrigerating sheet A, temperature sensor A, TEC refrigerating sheet B, temperature sensor B, TEC refrigerating sheet C, temperature sensor C are connected with controller respectively.By using means such as zoned collaborative temperature control, composite heat dissipation, active heat dissipation and sealed cavity, the stable operation of ultraviolet laser under harsh environment is realized.

Description

Technical Field

[0001] This utility model relates to the field of ultraviolet laser temperature control technology, specifically to a precision temperature control device for ultraviolet lasers used in harsh environments. Background Technology

[0002] Real-time and rapid monitoring of bioaerosols is of great significance in fields such as public health security, environmental monitoring, and bioterrorism. Detection based on laser-induced fluorescence technology has become the mainstream approach due to its high sensitivity and specificity, with ultraviolet lasers in the 200–400 nm range serving as the core excitation source due to their unique spectral characteristics and high photon energy.

[0003] Existing wide-temperature-range air-cooled ultraviolet lasers typically operate within a stable temperature range of 0–50°C. Within the temperature range of 10–40°C, the output power fluctuation of industrial-grade air-cooled ultraviolet equipment can be controlled within ±5%. Once this range is exceeded, the power attenuation rate typically exceeds 15% for every 10°C increase or decrease. This range is mainly limited by the heat dissipation efficiency of the air-cooling system and the thermal stability of the materials, specifically as follows: (1) When operating at high temperatures, the air-cooling system relies on the flow of ambient air for heat dissipation. When the external temperature approaches or exceeds 50°C, the heat dissipation capacity decreases significantly, causing the internal temperature of the laser to rise too quickly, which may lead to wavelength drift or exacerbate the thermal lensing effect of optical components, resulting in unstable output power; (2) In low-temperature environments, traditional air-cooling systems lack active heating functions, which may lead to condensation risks. When the ambient temperature is below the dew point, internal optical surfaces (such as cavity mirrors, crystals, etc.) are prone to condensation, increasing optical path scattering loss; (3) In extreme high and low temperature alternating environments, conventional heat dissipation structures are prone to thermal stress deformation, causing sealing failure or lens displacement, affecting the collimation of the optical path, thereby causing the resonant cavity to detune and the output power of the laser to decrease. The temperature control system of the laser not only plays a decisive role in the stability of the output power, but also greatly affects the long-term reliability of the laser system. Therefore, it is of great significance to develop a precision temperature control device for ultraviolet lasers suitable for harsh environments (-60~80°C).

[0004] It should be noted that the above content falls within the inventor's technical knowledge and does not necessarily constitute prior art. Utility Model Content

[0005] The purpose of this invention is to solve the problems existing in the prior art and provide a precision temperature control device for ultraviolet lasers in harsh environments. By adopting methods such as zoned collaborative temperature control, composite heat dissipation, active heat dissipation and sealed cavity, the ultraviolet laser can be stably operated in harsh environments and can be widely used in harsh environments such as aerospace and polar exploration.

[0006] This utility model achieves the above objectives by adopting the following technical solutions: A precision temperature control device for an ultraviolet laser in harsh environments includes an ultraviolet laser. The ultraviolet laser includes a housing with a cavity inside. The cavity contains substrates A and B. Substrate A has a pump light source mounted on it, and substrate B has an optical element, including at least one frequency-doubling crystal. A heating film is provided on the outer wall of the housing. At least one TEC (thermal energy dispersant) cooler A is located at the lower end of the housing, and a heat sink is also located at the lower end of the housing. The cold end of the TEC cooler A is attached to the housing, and the hot end is attached to the heat sink. A temperature control device is provided on the housing. Temperature sensor A; a TEC cooler B is provided on substrate A, with the cold end of the TEC cooler B attached to substrate A and the hot end attached to the housing, and a temperature sensor B is provided on substrate A; a TEC cooler C is provided on substrate B at a position corresponding to the frequency doubling crystal, with the cold end of the TEC cooler C attached to substrate B and the hot end attached to the housing, and a temperature sensor C is provided on substrate B; the heating film, TEC cooler A, temperature sensor A, TEC cooler B, TEC cooler C, and temperature sensor C are respectively connected to the controller.

[0007] The shell is sealed with a sealing ring and the cavity is filled with nitrogen for protection.

[0008] The optical window in the ultraviolet laser is coated with an anti-frost film.

[0009] The radiator is provided with several heat sinks, and a heat dissipation channel is formed between two adjacent heat sinks. The heat sink adopts a microchannel fin design, and the surface of the heat sink is filled with paraffin-based composite phase change material by friction stir welding technology.

[0010] The radiator is equipped with a high-powered cooling fan, which is connected to the controller.

[0011] The controller uses a microcontroller.

[0012] The present invention, by adopting the above-described structure, can bring the following beneficial effects: To address the differences in thermal characteristics among different laser components, a split-structure design and a zoned collaborative temperature control scheme are adopted to overcome the limitations of traditional single temperature control. Zoned collaborative temperature control is implemented for the housing, pump source, and optical components. A combined TEC semiconductor cooling and heating film approach is used to achieve a temperature control accuracy of ±0.05℃ in harsh environments (typically -60℃ to 80℃), and a PID algorithm is used to dynamically adjust parameters in each temperature zone. Secondly, a secondary independent temperature control is implemented for the nonlinear crystal, integrating a temperature-wavelength feedback closed loop. A microcontroller chip adjusts the crystal temperature control target value in real time, effectively compensating for phase mismatch caused by extreme temperatures, achieving a temperature control accuracy of up to ±0.001℃. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the structure of the precision temperature control device for ultraviolet lasers of this utility model; Figure 2 This is a schematic diagram of the structure of the radiator of this utility model; Figure 3 This is a schematic diagram showing the connection between the controller of this utility model and the temperature sensor and TEC cooling chip; In the diagram, 1. Housing, 2. Cavity, 3. Substrate A, 4. Substrate B, 5. Pump light source, 6. Frequency doubling crystal, 7. Heating film, 8. TEC cooler A, 9. Heat sink, 10. Temperature sensor A, 11. TEC cooler B, 12. Temperature sensor B, 13. TEC cooler C, 14. Temperature sensor C, 15. Controller, 16. Heat dissipation duct, 17. Paraffin-based composite phase change material, 18. High-speed cooling fan. Detailed Implementation

[0014] To more clearly illustrate the overall concept of this utility model, a detailed description will be provided below with reference to the accompanying drawings.

[0015] Many specific details are set forth in the following description in order to provide a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Therefore, the scope of protection of the present invention is not limited to the specific embodiments disclosed below.

[0016] The various embodiments in this specification are described in a progressive manner. The same or similar parts between the various embodiments can be referred to each other. Each embodiment focuses on describing the differences from other embodiments.

[0017] Furthermore, the terms “upper end”, “lower end”, “one side”, “A”, “B”, “C”, etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the location of the indicated technical feature.

[0018] In this utility model, unless otherwise explicitly specified and limited, the terms "provided with," "set up," and "connected" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0019] like Figure 1-3As shown, a precision temperature control device for an ultraviolet laser in harsh environments includes an ultraviolet laser. The ultraviolet laser includes a housing 1, and a cavity 2 is provided inside the housing 1. A substrate A3 and a substrate B4 are respectively provided inside the cavity 2. A pump light source 5 is provided on substrate A3, and an optical element is provided on substrate B4. The optical element includes at least one frequency doubling crystal 6. A heating film 7 is provided on the outer wall of the housing 1. The heating film 7 is a thin-film heating element that converts electrical energy into heat energy. At least one TEC (thermoelectric cooler) A8 is provided at the lower end of the housing 1. The TEC is also called a semiconductor cooler or thermoelectric cooler. A heat sink 9 is provided at the lower end of the housing 1. The cold end of the TEC A8 is attached to the housing 1, and the hot end is attached to the heat sink. A temperature sensor A10 is mounted on the housing 1, which is attached to the heat sink 9. A TEC cooler B11 is mounted on the substrate A3, with its cold end attached to the substrate A3 and its hot end attached to the housing 1. A temperature sensor B12 is mounted on the substrate A3. A TEC cooler C13 is mounted on the substrate B4 at the position corresponding to the frequency doubling crystal 6, with its cold end attached to the substrate B4 and its hot end attached to the housing 1. A temperature sensor C14 is mounted on the substrate B4. The heating film 7, TEC cooler A8, temperature sensor A10, TEC cooler B11, temperature sensor B12, TEC cooler C13, and temperature sensor C14 are all connected to the controller 15. This application addresses the differences in thermal characteristics of different components of the ultraviolet laser (e.g., housing heat dissipation, crystal frequency stabilization, LD efficiency, etc.) by adopting a split structure design and a zoned collaborative temperature control scheme, overcoming the limitations of traditional single temperature control. Zoned collaborative temperature control is implemented for the housing 1, the pump light source 5, and the optical components. Employing a synergistic approach of TEC semiconductor cooling and heating films, this system achieves a temperature control accuracy of ±0.05℃ in harsh environments (typically -60℃ to 80℃), dynamically adjusting parameters for each temperature zone using a PID algorithm. Secondly, it employs independent secondary temperature control for the nonlinear crystal, integrating a temperature-wavelength feedback closed loop. A microcontroller chip adjusts the crystal's temperature control target value in real time, effectively compensating for phase mismatch caused by extreme temperatures, achieving a temperature control accuracy of ±0.001℃. The housing module, pump light source module, and optical component module are independently packaged. High-power TEC coolers are embedded in the lower part of the laser housing using efficient heat conduction technology, rapidly dissipating heat accumulated at the hot end of the TEC cooler and ensuring stable operation even in environments with alternating high and low temperatures. This system meets the environmental adaptability and reliability requirements specified in the National Military Standard (GJB).

[0020] The housing 1 is sealed with a sealing ring, and the cavity 2 is filled with nitrogen for protection. Nitrogen protection can effectively isolate oxygen, prevent oxidation reactions, protect optical components, and improve cutting / welding quality.

[0021] The optical window of the ultraviolet laser is coated with an anti-frost film, which effectively prevents condensation and salt spray corrosion in low-temperature environments.

[0022] The radiator 9 is provided with several heat dissipation fins, and a heat dissipation air channel 16 is formed between two adjacent heat dissipation fins. The heat dissipation fins adopt a microchannel fin design, which helps to increase the heat dissipation surface area. The surface of the heat dissipation fins is filled with paraffin-based composite phase change material 17 through friction stir welding technology. This material undergoes a solid-liquid phase change at high temperature, which can quickly absorb the heat generated by the hot end of the TEC cooling chip A8, and transfer the heat to the microchannel fin radiator in a timely manner with the help of high thermal conductivity materials. The overall heat dissipation efficiency is 2-3 times higher than that of traditional fins.

[0023] The radiator 9 is equipped with a high-power cooling fan 18, which is connected to the controller 15. The high-power cooling fan 9, together with the professionally designed heat dissipation air duct, enables precise temperature control of each thermal management module.

[0024] The controller 15 uses a microcontroller. The microcontroller, in conjunction with a PID algorithm, dynamically adjusts the parameters of each temperature zone.

[0025] Instructions for use of the ultraviolet laser precision temperature control device of this application: First, based on the model or design parameters of the ultraviolet laser, the working environment of the housing 1, pump light source 5 (substrate A3), and optical components (substrate B4) is set to be stable.

[0026] First, temperature sensor A10 monitors the temperature of housing 1 in real time. When the temperature of housing 1 is low (usually below 0℃), especially at extremely low temperatures close to -60℃, the heating film 7 is activated by controller 15 to heat (preheat) housing 1. Once the temperature of housing 1 reaches 0~10℃, the TEC cooling chip A8 precisely controls the temperature of housing 1. Controller 15 uses PID feedback technology to control the temperature of housing 1, achieving a temperature control accuracy of ±0.05℃. This method significantly shortens the system's preheating time and reduces the heating power requirements of the TEC cooling chip. When temperature sensor A10 detects a high temperature in housing 1, the heating film 7 does not need to operate; the TEC cooling chip A8 can directly cool and control the temperature of housing 1. The heat sink 9 uses microchannel heat sinks to quickly dissipate the heat accumulated at the hot end of the TEC cooling chip A8, and utilizes air convection cooling duct 16 and a powerful cooling fan 18 to enhance overall heat dissipation capacity, ensuring stable operation even in environments with alternating high and low temperatures.

[0027] Based on the initial precise temperature control of the housing 1, secondary temperature control is then applied to the components on substrate A3 and substrate B4. Specifically, secondary temperature control of substrate A3 and its components is achieved through TEC cooler B11 and temperature sensor B12, while secondary temperature control of substrate B4 and its optical components is achieved through TEC cooler C13 and temperature sensor B14. This secondary temperature control achieves an ultra-high precision of ±0.001℃, significantly enhancing the overall stability of the laser system. A microcontroller-based control system enables seamless switching between the preheating stage and the TEC cooler temperature control stage. Furthermore, the automatic closed-loop control of the temperature control circuit ensures long-term stable and reliable operation within a wide temperature range of -60℃ to 80℃.

[0028] The above specific embodiments should not be construed as limiting the scope of protection of this utility model. For those skilled in the art, any alternative improvements or modifications made to the embodiments of this utility model shall fall within the scope of protection of this utility model.

[0029] Any aspects of this utility model not described in detail are known to those skilled in the art.

Claims

1. A precision temperature control device for an ultraviolet laser in harsh environments, comprising an ultraviolet laser, the ultraviolet laser including a housing, the housing having a cavity; characterized in that, The cavity contains substrate A and substrate B. Substrate A has a pump light source, and substrate B has an optical element, including at least one frequency doubling crystal. A heating film is provided on the outer wall of the housing. At least one TEC (Technology, Temperature, and Power) cooler A is located at the lower end of the housing, and a heat sink is located at the lower end of the housing. The cold end of the TEC cooler A is attached to the housing, and the hot end is attached to the heat sink. A temperature sensor A is located on the housing. TEC cooler B is located on substrate A, with its cold end attached to substrate A and its hot end attached to the housing. A temperature sensor B is located on substrate A. A TEC cooler C is located on substrate B at the position corresponding to the frequency doubling crystal, with its cold end attached to substrate B and its hot end attached to the housing. A temperature sensor C is located on substrate B. The heating film, TEC cooler A, temperature sensor A, TEC cooler B, TEC cooler C, and temperature sensor C are all connected to a controller.

2. The precision temperature control device for ultraviolet lasers in harsh environments according to claim 1, characterized in that, The shell is sealed with a sealing ring and the cavity is filled with nitrogen for protection.

3. The precision temperature control device for ultraviolet lasers in harsh environments according to claim 2, characterized in that, The optical window in the ultraviolet laser is coated with an anti-frost film.

4. The precision temperature control device for ultraviolet lasers in harsh environments according to claim 3, characterized in that, The radiator is provided with several heat sinks, and a heat dissipation channel is formed between two adjacent heat sinks. The heat sink adopts a microchannel fin design, and the surface of the heat sink is filled with paraffin-based composite phase change material by friction stir welding technology.

5. A precision temperature control device for ultraviolet lasers in harsh environments according to claim 4, characterized in that, The radiator is equipped with a high-powered cooling fan, which is connected to the controller.

6. A precision temperature control device for ultraviolet lasers in harsh environments according to claim 5, characterized in that, The controller uses a microcontroller.

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