A temperature control and vibration isolation device suitable for short-cavity single-frequency fiber lasers

Abstract

This utility model relates to a temperature control and vibration isolation device suitable for short-cavity single-frequency fiber lasers, belonging to the field of optical device technology. The device includes a vibration isolation plate, a cooling chip, a fiber optic encapsulation shell, an insulation shell, and a thermocouple. The vibration isolation plate is composed of an optical plate and a high-density shock-absorbing foam board. The fiber optic encapsulation shell is made of thermally conductive copper, with a cooling chip embedded at its bottom and tightly connected to the vibration isolation plate via thermally conductive silicone grease. The shell contains a heat-conducting groove for fixing the fiber cavity and a precise positioning groove for thermocouple temperature measurement. The insulation shell has an inner layer of Teflon material and an outer layer of high-density shock-absorbing foam, serving to isolate the influence of external ambient temperature and provide vibration isolation. By optimizing the heat dissipation path, enhancing the vibration isolation structure, and using a modular design, the problems of high heat dissipation cost, insufficient vibration isolation effect, and complex cavity length adjustment in existing technologies are solved. This device has advantages such as high temperature control efficiency, excellent vibration isolation performance, and ease of customization and integration. It can significantly improve the single-longitudinal mode stability and output power stability of single-frequency fiber lasers and enables wavelength tuning over a wide temperature range.

Description

Technical Field

[0001] This utility model belongs to the field of fiber laser packaging and precision temperature control technology, specifically relating to a temperature control and vibration isolation device for a short-cavity single-frequency fiber laser. By integrating temperature control and vibration isolation functions, it solves the problem of the influence of external environmental disturbances on laser performance and achieves wavelength tuning over a large temperature range. Background Technology

[0002] Single-frequency fiber lasers possess advantages such as narrow linewidth, low noise, and high stability, leading to their widespread application in gravitational wave detection, coherent lidar, laser cooling, and coherent optical communication, making them a research hotspot in recent years. However, the stability of single-frequency fiber lasers is extremely sensitive to changes in the external environment, particularly their single-frequency characteristics, frequency stability, and output power, which are easily affected by factors such as temperature, vibration, acoustic noise, humidity, and air pressure. Among these, distributed feedback (DFB) and distributed Bragg reflector (DBR) fiber lasers are widely used due to their short cavity size and ease of environmental isolation.

[0003] In the prior art, the vibration isolation and constant temperature structure disclosed in patent CN216121190U has the following defects:

[0004] 1. Low thermal conductivity: The size of the cooling chip is much larger than that of the optical fiber carrier, resulting in redundant heat conduction paths and high heat dissipation costs;

[0005] 2. Insufficient vibration isolation: Lacking specialized vibration isolation materials, relying solely on the outer casing seal is insufficient to effectively suppress high-frequency vibrations;

[0006] 3. Poor scalability: Adjusting the cavity length requires redesigning the overall structure, and optical path integration is difficult.

[0007] 4. Wavelength tuning: Only constant temperature is achieved, and the effect of wavelength tuning by changing temperature is not mentioned. Summary of the Invention

[0008] To address the problems of low thermal conductivity, insufficient vibration isolation performance, and poor scalability in existing temperature control and vibration isolation technologies for short-cavity single-frequency fiber lasers, this invention proposes a modular temperature control and vibration isolation device. By optimizing the heat dissipation path, introducing composite vibration isolation materials, and adopting a standardized packaging structure, the device significantly improves the stability and scalability of the laser.

[0009] The technical solution adopted in this utility model is as follows:

[0010] A temperature control and vibration isolation device suitable for short-cavity single-frequency fiber lasers, comprising:

[0011] The vibration isolation plate consists of an optical plate and a high-density damping foam board bonded underneath, forming a composite vibration isolation structure.

[0012] The fiber optic encapsulation shell, placed on the upper surface of the vibration isolation plate, consists of a lower copper main frame and an upper removable cover plate;

[0013] The cooling chip is embedded in the through slot at the bottom of the optical fiber encapsulation shell, and its lower surface is bonded to the vibration isolation plate through a thermally conductive silicone grease layer.

[0014] The heat-insulating shell covers the outer casing and has two openings on its side for routing the positive and negative wires of the optical fiber, thermocouple, and cooling chip.

[0015] Thermocouple is disposed in a temperature measuring groove inside the optical fiber encapsulation shell and is in close contact with the fiber laser cavity;

[0016] The thermocouple and the cooling element are respectively connected to the temperature controller.

[0017] The aforementioned fiber optic temperature control and vibration isolation device comprises an optical plate and a high-density shock-absorbing foam board. The optical plate is an anodized iron honeycomb plate adapted to the cavity size, and its size is determined according to the actual optical path system. The vibration isolation plate is composed of the optical plate and a high-density shock-absorbing foam board of the same size and 10cm thickness pasted underneath, which are bonded together by adhesive backing, and has both rigid support and low-frequency vibration absorption functions.

[0018] The aforementioned fiber optic temperature control and vibration isolation device uses a fiber optic encapsulation shell made of copper with a thermal conductivity ≥380 W / (m·K), comprising a lower main frame and a detachable cover plate, which are fixed by four M2 threaded holes.

[0019] In the aforementioned fiber optic temperature control and vibration isolation device, the bottom through-groove of the fiber optic encapsulation shell is a rectangular groove of the same size as the TEC cooling chip, and the groove is coated with thermally conductive silicone grease. After the TEC cooling chip is embedded, its upper and lower surfaces form thermally conductive interfaces with the shell body and the vibration isolation plate, respectively.

[0020] The aforementioned fiber optic temperature control and vibration isolation device has a fiber fixing slot within the main frame of the fiber optic encapsulation shell. The fiber fixing slot is a through-type square slot with a width and depth of 1mm, used to place the cavity part of the short-cavity single-frequency fiber laser. The slot is filled with thermally conductive silicone grease, which accelerates heat dissipation and fixes the fiber optic cable. The fiber laser cavity is fixed by thermally conductive silicone grease or adhesive and heat conduction is achieved.

[0021] The aforementioned fiber optic temperature control and vibration isolation device has a temperature measuring groove that is a rounded square groove adapted to the size of the temperature measuring thermocouple and with the temperature measuring point close to the location of the gain fiber. It is set close to the fiber cavity and is used to fix the thermocouple.

[0022] The fiber optic encapsulation shell has a rounded square slot on the left side of the central square slot, which is adapted to the size of the thermocouple and is used to place the thermocouple for accurate measurement of the cavity temperature. The lower surface of the fiber optic encapsulation shell has a square slot adapted to the size of the TEC cooling chip, which is used to embed the cooling chip.

[0023] The aforementioned temperature control and vibration isolation device has a cooling chip embedded in an optical fiber encapsulation shell, with its lower surface coated with thermally conductive silicone grease and tightly connected to the vibration isolation plate to improve the thermal coupling efficiency with the vibration isolation plate. Both the cooling chip and the thermocouple are equipped with positive and negative terminals, and after being connected to the adapter plate, they are connected to the temperature controller to form a closed-loop temperature control system.

[0024] In the aforementioned temperature control and vibration isolation device, the main body of the optical fiber encapsulation shell is fixed above the vibration isolation plate with copper foil tape after the cooling chip is embedded.

[0025] The aforementioned temperature control and vibration isolation device comprises an inner insulation layer and an outer vibration isolation layer. The inner insulation layer is made of Teflon material with heat-insulating properties, and the outer vibration isolation layer is made of high-density vibration-damping foam. The insulation shell covers the outside of the optical fiber encapsulation shell to isolate it from the influence of external ambient temperature and vibration.

[0026] The beneficial effects of this utility model are:

[0027] 1. High-efficiency temperature control: The cooling element is directly embedded in the bottom of the copper shell, shortening the heat conduction path by 50%. Combined with real-time thermocouple feedback, the temperature control accuracy can reach ±0.001℃, and the temperature range is wide, from 0℃ to 210℃.

[0028] 2. Composite vibration isolation: The combination of optical flat plate and high-density foam can suppress low-frequency vibrations and greatly reduce the amplitude;

[0029] 3. Modular design: The cavity length can be adjusted simply by replacing the corresponding length of the package shell. Optical components (such as pump source and wavelength division multiplexer) can be integrated on the surface of the vibration isolation plate, which has strong expandability.

[0030] 4. High reliability: The fiber cavity is fixed in a 1mm wide square groove 201 by filling it with thermally conductive silicone grease, avoiding the risk of breakage caused by stress concentration at the melting point. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the structure of the present utility model.

[0032] Figure 2 Diagram of a vibration-isolated flat plate structure

[0033] Figure 3 Fiber optic packaging shell structure diagram

[0034] Figure 4 Diagram of the thermal insulation shell structure

[0035] Figure 5 This is a working example diagram of the present utility model.

[0036] Figure 6 The figures show the single longitudinal profile curves before and after using this invention. (a) shows the single longitudinal profile curve before using this invention, and (b) shows the single longitudinal profile curve after using this invention.

[0037] Figure 7 The wavelength tuning curves of this invention are shown in (a) and (b) respectively. (a) is the wavelength tuning spectrum, and (b) is the wavelength versus temperature curve.

[0038] Figure 8 Temperature stability curve of this utility model

[0039] 1 is a vibration isolation plate, 2 is the main body of the optical fiber packaging shell, 3 is the upper cover plate of the optical fiber packaging shell, 4 is a cooling plate, 5 is a thermal insulation shell layer, 6 is a wavelength division multiplexer, 7 is a power adapter board, 8 is the positive and negative wires of the thermocouple, 9 is a temperature control terminal, 10 is a 915nm LD pump source, 101 is an optical plate, 102 is vibration isolation cotton, 201 is a light fixing slot, 202 is a thermocouple fixing slot, 203 is a cooling plate fixing slot, 401 is the positive and negative wires of the cooling plate, 501 is a Teflon material shell, and 502 is... Detailed Implementation

[0040] like Figure 1-5 As shown, the high-stability fiber optic temperature control and vibration isolation device includes a vibration isolation plate 1, a fiber optic encapsulation shell 2, an encapsulation shell cover plate 3, a cooling plate 4, an insulation shell 5, and a thermocouple 8. The cooling plate 4 is placed above the vibration isolation plate, and is fixed by applying thermally conductive silicone grease to its lower surface for heat dissipation. The fiber optic encapsulation shell 2 is placed above the cooling plate, and the cooling plate is embedded in the bottom of the encapsulation shell. The upper part of the encapsulation shell has square and rectangular slots for placing the fiber optic cable and the thermocouple. The cover plate is placed on top and fixed with M2 screws. The insulation shell 5 covers the outside of the fiber optic encapsulation shell to isolate it from the influence of external ambient temperature and vibration.

[0041] like Figure 2 As shown, the vibration isolation plate 1 is composed of an optical plate 101 with dimensions of 200×300×13 (mm) and a 5cm thick vibration isolation cotton 102 of the same size. The vibration isolation cotton has self-adhesive backing and is attached to the bottom of the optical plate to isolate vibration and prevent moisture.

[0042] like Figure 3As shown, the fiber optic encapsulation shell consists of a lower fiber optic encapsulation shell body 2 and a cover plate 3, both with M2 screw holes at their four corners for fixing. The upper part of the fiber optic encapsulation shell 2 has a through-hole square groove 201 (1mm wide), a long groove 202 (2mm wide, 1mm deep, and 6cm long), and a through-hole long groove 203 (1.5mm deep and 13mm wide). The square groove 201 is used to place the fiber optic cavity or gain fiber; after placing the fiber, the groove is filled with thermally conductive silicone grease to enhance heat transfer and fix the fiber. The long groove 202 is used to place a thermocouple, positioned close to the gain fiber for more accurate temperature measurement. The long groove 203 is used to place a cooling pad; thermally conductive silicone grease is applied under the cooling pad to increase heat dissipation and fix it in place.

[0043] like Figure 4 As shown, the thermal insulation shell consists of an inner Teflon material shell 501 and an outer high-density vibration-damping foam 502. The Teflon material is used for thermal insulation, and the high-density vibration-damping foam is used for sound absorption and vibration isolation, thus isolating the influence of external environmental temperature and vibration.

[0044] like Figure 5 As shown, the 978nm DBR structure short-cavity single-frequency fiber laser consists of a 915nm LD pump source 10, a 915 / 978nm wavelength division multiplexer 6, and a short cavity within the fiber optic enclosure 2. The entire laser is fixed above a vibration-isolated plate, facilitating integration and relocation. The positive and negative terminals of the cooling pad 401 and the positive and negative terminals of the thermocouple 8 are connected to the adapter plate 7 and then to the temperature controller 9. Thermocouple 8 monitors the cavity temperature in real time and controls the cooling pad 4 to change the cavity temperature through the temperature controller 9 to achieve temperature control. Figure 6 (a) is the single longitudinal mold property curve before the addition of the vibration isolation and temperature control device. The single longitudinal mold property is unstable and there are problems such as mold jumping. Figure 6 (b) is the single longitudinal mode characteristic curve after the addition of the temperature control vibration isolation device, which achieves stable single longitudinal mode output at various temperatures. Figure 7 (a) and (b) show the wavelength tuning curves of the system under varying temperature conditions from 0 to 210℃. Uniform temperature variation and stabilization at each temperature point achieved wavelength tuning of 1.5 nm. Figure 8 The temperature stability curve of the system measured at 30℃ for 1 hour shows a temperature fluctuation of only 0.01%. This demonstrates that the temperature-controlled vibration isolation device effectively reduces the influence of the external environment, providing vibration isolation and heat preservation, and is easy to adjust for wavelength tuning and system integration.

[0045] The technical features of this utility model correspond completely to the claims, including the vibration isolation plate structure, the tank design with a copper outer shell, the heat insulation shell design, and the integration method of the cooling element and the thermocouple, etc., ensuring the feasibility of the technical solution and the clarity of the patent protection scope. The above embodiments are only preferred solutions of this utility model. Those skilled in the art can make adaptive adjustments without departing from the principle of this utility model, such as changing the vibration isolation material or adjusting the tank size. Such improvements are all within the protection scope of this utility model.

Claims

1. A temperature control and vibration isolation device suitable for a short-cavity single-frequency fiber laser, characterized in that, include: The vibration isolation plate consists of an optical plate and a high-density damping foam board bonded underneath, forming a composite vibration isolation structure. The fiber optic encapsulation shell, placed on the upper surface of the vibration isolation plate, consists of a lower copper main frame and an upper removable cover plate; The cooling chip is embedded in the through slot at the bottom of the optical fiber encapsulation shell, and its lower surface is bonded to the vibration isolation plate through a thermally conductive silicone grease layer. The heat-insulating shell covers the top of the encapsulation shell, and has two holes on the side for the routing of positive and negative wires of optical fiber, thermocouple and cooling chip; Thermocouple is disposed in a temperature measuring groove inside the optical fiber encapsulation shell and is in close contact with the fiber laser cavity; The thermocouple and the cooling element are respectively connected to the temperature controller.

2. The temperature control and isolation device of claim 1, wherein, The optical plate of the vibration isolation plate is an anodized iron honeycomb plate, and its size is determined according to the actual optical path system. The high-density shock-absorbing foam board has a thickness of 5cm and is the same size as the optical plate.

3. The temperature control and isolation device of claim 1, wherein, The bottom through-groove of the optical fiber packaging shell is a rectangular groove of the same size as the TEC cooling chip, and the groove is coated with thermally conductive silicone grease. After the TEC cooling chip is embedded, its upper and lower surfaces form thermally conductive interfaces with the shell body and the vibration isolation plate, respectively.

4. The temperature control and isolation device of claim 1, wherein, The main frame of the fiber optic encapsulation shell is provided with a fiber fixing groove. The fiber fixing groove is a through square groove with a width and depth of 1mm. The groove is filled with thermally conductive silicone grease. The fiber laser cavity is fixed by thermally conductive silicone grease or adhesive dispensing and heat conduction is achieved.

5. The temperature control and isolation device of claim 1, wherein, The temperature measuring groove is a rounded square groove that is adapted to the size of the temperature measuring thermocouple and has the temperature measuring point close to the location of the gain fiber. It is set close to the fiber cavity and is used to fix the thermocouple.

6. The temperature control and isolation device of claim 3, wherein, The positive and negative terminals of the TEC cooling element and thermocouple are connected to the temperature controller via an adapter plate to achieve closed-loop temperature control.

7. The temperature-controlled and vibration-isolated device of claim 1, wherein The optical fiber encapsulation shell is fixed to the vibration isolation plate with copper foil tape, and the overall structure supports modular expansion, with optical path devices integrated on the surface of the vibration isolation plate.

8. The temperature-controlled and vibration-isolated device of claim 1, wherein, The thermal insulation shell consists of a Teflon thermal insulation inner layer and high-density vibration damping foam. Its size is adapted to the fiber optic encapsulation shell and covers the outside of it to isolate it from the influence of external environmental temperature and vibration.

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