Laser gyroscope combined type slotted vane based on optical cement technology

Abstract

The invention discloses a laser gyroscope combined type slotted vane based on an optical cement technology, and aims to solve the problems that an existing slotted vane is easy to bend and twist in long-range scanning, helium is leaked, the sensitivity is low, the stability is not high and the like. The device is composed of a microcrystalline glass ring, a fused quartz cylinder and an annular groove bottom. The upper end face and the lower end face of the glass ceramic ring are polished into polished planes capable of being subjected to optical cement, and fused quartz cylinders are coaxially nested in the polished planes. The lower surface of the fused quartz cylinder is an optical cement polishing plane, and the upper surface of the fused quartz cylinder is an ultra-smooth coating reflecting surface; the bottom of the annular groove adopts a glass-ceramic double-sided polishing sheet, the upper surface and the lower surface are polished, and the upper surface is connected with the lower surfaces of the glass-ceramic ring and the fused quartz cylinder through optical cement. The problems that the thickness of the annular groove bottom is not uniform, fused quartz glass is prone to leakage and the like are solved, bending and twisting in long-range scanning are eliminated, the axial deformation range in the groove sheet can be effectively improved, the sensitivity and the stability are high, and the overall performance of the gyroscope is improved.

Description

Technical Field

[0001] The present invention relates to an important component of a laser gyroscope, and particularly refers to a combined slot plate used in a laser gyroscope for constructing a ring-closed optical path and suitable for controlling the length of the ring-closed optical path and adjusting the resonant optical path. Background Art

[0002] A laser gyroscope is a precision instrument for measuring the angular motion of a carrier. As a typical inertial measurement instrument, it is mainly used in various occasions such as navigation and guidance, stable aiming and orientation, positioning and orientation, attitude measurement, and overload sensing of various motion systems and platforms in both military and civilian technical fields, and is known as the "pearl" on the inertial navigation system. As a typical representative of optical gyroscopes, a laser gyroscope is essentially a ring helium-neon laser, which uses the Sagnac effect and laser technology to achieve high-precision angular motion measurement of a moving carrier, and is regarded as one of the most successful application cases of laser technology. As Figure 1 shown, a typical laser gyroscope mainly consists of two slot plates 1 (with catches 2 adhered to the rear side thereof), two plane mirrors 3, and a gyro housing 4. The gyro housing 4 is filled with helium-neon gas 5. Among them, the two slot plates 1 and the two plane mirrors 3 are respectively fixed on the four bonding surfaces 4a of the gyro housing 4 by optical cementing. High-reflectivity optical films are plated on the central regions of the two slot plates 1 and the two plane mirrors 3 to achieve geometric constraint on the resonant laser in the gyro housing 4, thereby forming a ring-closed optical path (as Figure 1 shown by the red-line square frame in); the gyro housing 4 is machined with a light-passing channel, which forms a sealed space due to optical cementing sealing. Helium-neon gas 5 is filled into this sealed space to provide gain for the laser resonance in the gyro housing 4. As Figure 1 shown, there are two beams of light rotating clockwise and counterclockwise in the ring-closed optical path in the gyro housing 4. The laser gyroscope uses the linear variation law of the frequency difference △ν between the clockwise resonant light CW and the counterclockwise resonant light CCW in the ring-closed optical path with the rotation speed Ω of the laser gyroscope carrier to achieve angular motion measurement, that is:

[0003] △ν = 4AΩ / Lλ (1)

[0004] In the formula, A is the area surrounded by the annular closed optical path, L = n·l is the optical length of the annular closed optical path (where n is the refractive index in the annular closed optical path and l is the geometric length of the annular closed optical path), and λ is the laser wavelength. It can be seen from Equation (1) that in order to achieve high-performance measurement of the carrier rotation speed Ω of the laser gyroscope, the laser gyroscope has extremely high requirements for the stability of the optical path. This has led laser gyroscope research and development units at home and abroad to invariably choose glass-ceramics, a material with an extremely low coefficient of thermal expansion, as the gyroscope cavity 4. At the same time, a practical laser gyroscope also needs to be equipped with a path length adjustment mirror that can actively control the cavity length. Under the control of the frequency stabilization circuit, the stability of the laser operating frequency (or wavelength) is achieved, so that the laser gyroscope has good linearity, repeatability, and stability. The grooved plate 1 is a special structure mirror used to achieve the path length control and optical path adjustment of the laser gyroscope. Its cross-sectional view along the axial direction (OO' direction) is as Figure 2 shown. The outer shape of the grooved plate 1 is usually cylindrical, and annular grooves 14 with different depths are opened on the upper and lower cylindrical surfaces, thus forming its main structure: the small column 111, the circular column 112, and the annular groove bottom 13. The three are combined into a whole. Among them, the end face of the small column 111 on the O' side is the reflecting surface 11a, and the end face of the circular column 112 on the O' side is the optical cementing surface 12a. Therefore, the grooved plate 1 has both the functions of a mirror and path length control. As Figure 2 shown, the grooved plate 1 is usually bonded to the chuck 2 for cooperative use. Among them, the chuck 2 is mainly composed of a metal skeleton 21, a piezoelectric ceramic sheet 22, and a thimble 23. By applying different voltages to the piezoelectric ceramic sheet 22, the thimble 23 is axially deformed and acts on the lower surface of the small column 111 of the grooved plate 1. By using the elastic deformation of the annular groove bottom 13 in the OO' direction, the geometric length l of the annular closed optical path of the laser gyroscope is changed.

[0005] In the development of ring laser gyroscopes, the optical cemented surface 12a of the cell 1 is fixed to the bonding surface 4a of the gyroscope cavity 4 by optical cementing. Therefore, when selecting the material for the cell 1, to avoid the optical cemented surface 12a coming unstuck from the bonding surface 4a of the gyroscope cavity 4 due to different expansion amounts caused by temperature changes, which may lead to air leakage, the thermal expansion coefficient of the mirror material should be as consistent as possible with that of the gyroscope cavity 4. Therefore, using glass-ceramics to make the mirror substrate material is the most ideal choice. However, due to the good material properties of fused silica glass, it is easier to achieve polishing of an ultra-smooth surface with extremely low roughness compared to glass-ceramics. Therefore, high-precision ring laser gyroscopes generally use fused silica glass as the material for the cell 1. However, this will cause the relatively thin annular groove bottom 13 of the cell 1 to be prone to helium leakage (helium atoms are more likely to leak compared to neon atoms), which affects the working life of the ring laser gyroscope. To solve these problems, in 2004, a new type of composite cell for ring laser gyroscopes invented by Jin Shilong et al. (patent number 200420069089.9) consists of a cell substrate and a cell reflector. Among them, the cell substrate is prepared from glass-ceramics material, and its structure is similar to the small pillar 111 and the circular ring pillar 112 in the cell 1 in Figure 2 . The difference between the two is that Figure 2 the reflecting surface 11a of the cell 1 in Figure 2 is a coated reflecting surface, while the reflecting surface 11a in the new type of composite cell is not coated but polished into an optical cemented surface; the cell reflector in the new type of composite cell is equivalent to Figure 2 the reflecting surface 11a, is a thin sheet structure, prepared from fused silica glass, one side is polished into an optical cemented surface, and the other side is super-polished to form a coated reflecting surface. The reflecting surface 11a of the cell substrate and the optical cemented surface of the cell reflector are bonded into a whole by optical cementing. It can be seen that this solution combines the advantages of extremely low thermal expansion coefficient and no helium leakage of glass-ceramics, as well as good uniformity, high hardness, and easy processing of an ultra-smooth surface of fused silica glass. Moreover, the microcrystalline cell substrate and the cell reflector are processed separately, the difficulty is reduced, and the yield is increased, which can improve the stability, reliability, and high and low temperature performance of the ring laser gyroscope.

[0006] However, this new type of composite cell still has the following problems: 1. Limited by the existing processing method of the annular groove 14, axial ([[]]END]] Figure 2In the case of the annular groove bottom 13 deforming in the direction parallel to the OO' arrow, the uniformity of the thickness h still cannot be guaranteed, and this thickness non-uniformity will inevitably cause the slot piece 1 to bend and twist during the pushing and pulling process. This bending and twisting is more serious under variable temperature conditions, resulting in the deflection of the resonant optical path in the laser gyro cavity 4 and affecting the accuracy and high and low temperature performance of the laser gyro; 2. For a slot piece with a smaller slot piece diameter D1 (equal to the outer diameter of the circular cylinder 112), since the area of the annular groove bottom 13 becomes smaller, it is very difficult for the composite new slot piece to maintain its axial deformation amount by further thinning the thickness h of the annular groove bottom 13. Especially when the thickness h of the annular groove bottom 13 is thinned to 0.5 mm, the phenomenon of cracking of the annular groove bottom 13 is likely to occur; 3. The contradiction between the radial stiffness of the slot piece and the axial stroke pushing and pulling range cannot be solved. That is, when the size of the slot piece is determined, if the radial thickness of the circular cylinder 112 of the slot piece 1 (equal to D1 - D5, where D5 is the inner diameter of the circular cylinder 112) is increased to enhance the radial stiffness of the slot piece, it will inevitably lead to a smaller deformation area of the annular groove bottom 13 and a shorter axial stroke pushing and pulling range of the slot piece; 4. The composite new slot piece structure cannot solve the contradiction between the area of the optical cement surface 12a of the slot piece and the axial deformation of the annular groove bottom 13, making it impossible for the laser gyro to take into account its performance in terms of reliability and temperature adaptability, etc.

[0007] In summary, how to improve problems such as bending and twisting during the axial deformation of traditional slot pieces due to their own structural defects through slot piece structure innovation and process optimization, and further enhance the stability and environmental adaptability of the slot piece is a technical problem that those skilled in the art are extremely concerned about. Summary of the Invention

[0008] The technical problem to be solved by the present invention is to provide a combined slot piece for a laser gyro based on an optical cementing process to address defects such as non-uniform thickness of the annular groove bottom, contradiction between the radial stiffness of the slot piece and the axial stroke pushing and pulling range, and contradiction between the area of the optical cement surface of the slot piece and the axial deformation of the annular groove bottom 13 in the prior art, which lead to problems such as bending and twisting, helium leakage, low sensitivity, low reliability and stability during the stroke scanning. In this combined slot piece, the microcrystalline glass ring and the annular groove bottom 13 have a small thermal expansion coefficient and a low helium leakage rate, and the surface roughness of the fused silica glass cylinder is extremely low. At the same time, a series of problems such as insufficient sensitivity and bending and twisting during the pushing and pulling process introduced due to the processing of the thickness of the annular groove bottom 13 are solved, further improving the environmental adaptability, reliability and stability of the gyro, and meeting the technical requirements and usage requirements of high-performance laser gyros for high-quality stroke control mirrors.

[0009] The technical solution of the present invention is as follows:

[0010] The combined slot piece for a laser gyro based on an optical cementing process is composed of a microcrystalline glass ring 12, a fused silica cylinder 11 and an annular groove bottom.

[0011] The glass-ceramic ring has a circular ring structure and is made of glass-ceramic. Its outer diameter is the diameter D1 of the groove piece, where D1 ≤ the side length of the bonding surface of the laser gyro cavity. D1 is preferably 6 - 30 mm. The inner diameter D2 of the glass-ceramic ring is D1 - 2 - 10 mm, and the thickness H of the glass-ceramic ring is 1 - 8 mm. The upper and lower end faces of the glass-ceramic ring are polished into parallel planes to form polished planes that can be photo-cemented, with the requirement that the number of fringes ≤ 0.5, local fringes ≤ 0.3, and roughness ≤ 1 nm. A fused silica cylinder is coaxially nested inside the glass-ceramic ring;

[0012] The fused silica cylinder is cylindrical, with a height equal to the thickness H of the glass-ceramic ring. The diameter d of the fused silica cylinder < D2 - 0.01 mm, and the lower surface of the fused silica cylinder is a polished plane that can be photo-cemented. The upper surface, i.e., the reflecting surface, is a highly reflective coating surface with ultra-smoothness (roughness ≤ 0.1 nm). The fused silica cylinder is coaxially nested inside the glass-ceramic ring; The reflecting surface 11a is a concave spherical surface, a convex spherical surface, or a plane, and a high-reflection film (reflectivity ≥ 99%) is deposited on the reflecting surface; The fused silica cylinder can also adopt a composite structure of glass-ceramic and fused silica glass, that is, part of the cylinder is made of glass-ceramic and part of the cylinder is made of fused silica glass. The two are compounded into one body in a coaxial photo-cementing manner, with the glass-ceramic cylinder at the bottom and the fused silica glass cylinder on top. The total height of the two parts is equal to the thickness H of the glass-ceramic ring, and the upper surface of the fused silica cylinder is used as the reflecting surface;

[0013] The bottom of the annular groove of the present invention uses a double-sided polished glass-ceramic thin sheet, which has a disc shape and is made of glass-ceramic. It is coaxially placed below the glass-ceramic ring and the fused silica cylinder. Both the upper surface and the lower surface are polished, and the upper surface is photo-cemented to the lower surface of the glass-ceramic ring and the lower surface of the fused silica cylinder. The outer diameter D3 of the bottom of the annular groove satisfies D2 < D3 ≤ D1, and the thickness h is 0.1 - 5 mm. The bottom of the annular groove can deform under the action of the axial thimble generated by the inverse piezoelectric effect of the clamping piezoelectric ceramic, thereby generating a micron-scale displacement change along the OO' axis; After the double-sided polishing of the bottom of the annular groove, various etching processes, such as chemical etching, ion beam etching, laser etching, etc., can also be used to reduce the thickness h of the thin sheet to less than 0.1 mm, effectively improving the axial deformation range in the groove piece;

[0014] The glass-ceramic used for the glass-ceramic ring, the fused silica cylinder, and the bottom of the annular groove is the same as the glass-ceramic used for the laser gyro cavity to be assembled. It is also possible to directly use mechanical milling to process a boss at the bonding surface of the laser gyro cavity. The height of the boss is the thickness H of the glass-ceramic ring. Replace the glass-ceramic ring with the boss. After the fused silica glass cylinder is photo-cemented to the center of the bottom of the annular groove 13, the bottom of the annular groove is then directly photo-cemented to the bonding surface of the boss of the laser gyro cavity with the boss, forming the present invention;

[0015] In order to increase the axial deformation of the annular groove bottom at OO', a circular countersunk hole with a diameter of D4 can be processed on the smooth adhesive surface where the microcrystalline glass ring and the annular groove bottom are bonded, and D2 <D4<D1,圆形沉孔的深度h2大于1μm,通过减少环形槽底的光胶面积来增大环形槽底的形变区域。

[0016] In order to increase the ability of the present invention to resist rapid temperature changes and high-intensity mechanical vibration impact in a vacuum environment, the fused quartz cylinder and the annular groove bottom can also be connected into one by deepening optical glue; the microcrystalline glass ring and the annular groove bottom can only be connected by ordinary optical glue, with the annular groove bottom at the bottom and the microcrystalline glass ring at the top.

[0017] When the present invention is used, at least one laser gyroscope combined slot plate based on the optical glue process of the present invention can be installed in the laser gyroscope, and the distance from the patch surface of the gyroscope cavity equipped with the laser gyroscope of the present invention to the center intersection of the two optical path holes in the gyroscope cavity should be exactly equal to the thickness H of the fused quartz glass cylinder.

[0018] The present invention maintains the characteristics of extremely low thermal expansion coefficient and no helium leakage of microcrystalline glass, as well as the advantages of easy processing and high polishing quality of fused quartz glass, and overcomes the problems of uneven thickness of the annular groove bottom and easy leakage of fused quartz glass.

[0019] Compared with the prior art, the present invention can achieve the following technical effects:

[0020] 1. The annular groove bottom of the present invention is processed by double-sided parallel polishing instead of mechanical grinding, which effectively eliminates the bending and twisting problem during long-range scanning caused by uneven thickness of the annular groove bottom of the traditional groove sheet;

[0021] 2. In the existing technical solutions, the thickness h of the annular groove bottom of the groove sheet is limited by the mechanical grinding method, and the thinnest can only be about 0.5 mm, otherwise the groove bottom is prone to cracking or even breaking. The double-sided polishing and various etching processes adopted by the present invention, such as chemical etching, ion beam etching, laser etching and other processes, can reduce the thickness h of the thin sheet to less than 0.1 mm, which can effectively improve the axial deformation range of the groove sheet;

[0022] 3. The glass-ceramic ring, fused quartz cylinder and annular groove bottom are processed separately, which reduces the difficulty of processing technology, improves the yield rate, and expands the batch production efficiency and output, which is more conducive to the cost control of the gyroscope. At the same time, it breaks the limitation of the traditional processing method on the spherical curvature when the reflective surface is a spherical surface;

[0023] 4. The ultrasmooth surface of a fused silica cylinder is used as the coated reflective surface, enabling the coated reflective surface to have a high ability to resist rapid temperature changes and high-intensity mechanical vibration impacts; the glass-ceramic ring is made of glass-ceramic, which is the same as the material of the laser gyro cavity. When the temperature changes, air leakage will not occur due to different expansion amounts, which would cause the optical cemented surface between the groove piece and the gyro to come unsealed, thus improving the overall performance of the gyro. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 is a schematic diagram of the structure of the existing laser gyro described in the background art;

[0025] Figure 2 is an axial sectional view of the conventional groove piece and its supporting chuck described in the background art;

[0026] Figure 3 General structure diagram of the present invention.

[0027] Figure 4 is Figure 3 A sectional view along the A-A' direction. Figure 4 (a) is Figure 3 A sectional view along the A-A' direction, Figure 4 (b) is Figure 4 A 4:1 enlarged schematic view at the position of the circle in (a).

[0028] Figure 5 is a deformation diagram of the groove piece 1 under a 1N acting force of the chuck 2 simulated by using Solidwords software. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0029] The following further describes the specific embodiments of the present invention in conjunction with the drawings and examples.

[0030] As Figure 3 shown, the laser gyro combined groove piece based on the optical cementing process of the present invention is composed of a glass-ceramic ring 12, a fused silica cylinder 11, and an annular groove bottom 13.

[0031] As Figure 3 shown, in combination with Figure 4 (a), the glass-ceramic ring 12 is a circular ring structure, prepared from glass-ceramic. Its outer diameter is the groove piece diameter D1, D1 ≤ the side length of the bonding surface 4a of the laser gyro cavity, and D1 is preferably 6 - 30 mm. The inner diameter D2 of the glass-ceramic ring 12 = D1 - 2 - 10 mm, and the thickness H of the glass-ceramic ring 12 is 1 - 8 mm. The upper and lower end faces of the glass-ceramic ring 12 are polished into parallel planes to form polished planes for optical cementing, with the requirements of the number of fringes ≤ 0.5, local fringes ≤ 0.3, and roughness ≤ 1 nm. A fused silica cylinder 11 is coaxially nested inside the glass-ceramic ring 12;

[0032] The fused silica cylinder 11 is cylindrical, with a height equal to the thickness H of the glass-ceramic ring 12. The diameter d of the fused silica cylinder 11 satisfies d < D2 - 0.01 mm. The lower surface of the fused silica cylinder 11 is a polished plane that can be photo-cemented, and the upper surface, i.e., the reflective surface 11a, is a highly reflective coating surface with ultra-smoothness (roughness ≤ 0.1 nm). The fused silica cylinder 11 is coaxially nested within the glass-ceramic ring 12; the reflective surface 11a is a concave spherical surface, a convex spherical surface, or a plane, and a high-reflection film (reflectivity ≥ 99%) is deposited on the reflective surface 11a; the fused silica cylinder 11 can also adopt a composite structure of glass-ceramic and fused silica glass, that is, part of the cylinder is made of glass-ceramic and part of the cylinder is made of fused silica glass. The two are compounded into one body in a coaxial photo-cementing manner, with the glass-ceramic cylinder at the bottom and the fused silica glass cylinder at the top. The total height of the two parts is equal to the thickness H of the glass-ceramic ring, and the upper surface of the fused silica cylinder 11 is used as the coating reflective surface 11a;

[0033] The bottom 13 of the annular groove is made of a double-sided polished thin slice of glass-ceramic, with a disc-shaped appearance, prepared from glass-ceramic, coaxially placed below the glass-ceramic ring 12 and the fused silica cylinder 11. Both the upper surface and the lower surface are polished, and the upper surface is photo-cemented to the lower surfaces of the glass-ceramic ring 12 and the fused silica cylinder 11. The outer diameter D3 of the bottom 13 of the annular groove satisfies D2 < D3 ≤ D1, and the thickness h is 0.1 - 5 mm. The bottom 13 of the annular groove can deform under the action of the axial ejector pin 23 generated by the inverse piezoelectric effect of the clamping 2 piezoelectric ceramic, thereby generating a displacement change in the micron order along the OO' axis; after the bottom 13 of the annular groove is double-sided polished, various etching processes, such as chemical etching, ion beam etching, laser etching, etc., can be used to reduce the thickness h of the thin slice to less than 0.1 mm, effectively increasing the axial deformation range in the groove piece;

[0034] The glass-ceramic used in the glass-ceramic ring 12, the fused silica cylinder 11, and the bottom 13 of the annular groove is the same as the glass-ceramic used in the laser gyro cavity to be assembled. Alternatively, a convex platform can be directly machined at the photo-cementing surface 4a of the laser gyro cavity by mechanical milling. The height of the convex platform is the thickness H of the glass-ceramic ring 12. Using the convex platform to replace the glass-ceramic ring 12, after the fused silica glass cylinder 11 is photo-cemented to the center of the bottom 13 of the annular groove, the bottom 13 of the annular groove is then directly photo-cemented to the convex platform photo-cementing surface 4a of the laser gyro cavity with the convex platform, forming the present invention;

[0035] To increase the axial deformation of the bottom 13 of the annular groove in the OO' direction, as Figure 4 (b) shows, a circular counterbore 12b with a diameter of D4 can be machined on the photo-cementing surface where the glass-ceramic ring 12 is bonded to the bottom 13 of the annular groove, and D2 < D4 < D1. The depth 10 μm < h2 < h of the circular counterbore 12b. By reducing the photo-cementing area of the bottom 13 of the annular groove, the deformation area of the bottom 13 of the annular groove is increased.

[0036] To enhance the ability of the present invention to resist rapid temperature changes and high-intensity mechanical vibration impacts in a vacuum environment, the fused silica cylinder 11 and the annular groove bottom 13 can also be connected into one body by deepening the optical cementing method; only ordinary optical cementing can be used between the glass-ceramic ring 12 and the annular groove bottom 13, with the annular groove bottom 13 at the bottom and the glass-ceramic ring 12 on top.

[0037] To verify the effect of the present invention, Example 1 of the present invention was prepared as follows: D1 = D3 = 25 mm, D2 = 10 mm, D4 = 18.6 mm, d = 6.0 mm, H = 6.0 mm, h = 0.5 mm, h2 = 0.2 mm. Since the number of interference fringes, local interference fringes, roughness, and the roughness of the reflective surface 11a have no effect on the thickness and thickness uniformity of the annular groove bottom 13 when the upper and lower end faces of the glass-ceramic ring 12 are polished into parallel planes, to simplify the experimental process, when using Solidwords software (version 2020 or above) to simulate the deformation of the groove piece 1 under the 1N acting force of the gripper 2, the number of interference fringes N = 0, local interference fringes ΔN = 0, roughness = 0, and the roughness of the reflective surface 11a = 0 were set when the upper and lower end faces of the glass-ceramic ring 12 were polished into parallel planes. The deformation diagram of the groove piece 1 simulated by using Solidwords software under the 1N acting force of the gripper 2 is as Figure 5 shown, and the maximum deformation is about 95.6 nm. It can be seen from the color of the simulation diagram (representing the displacement, from blue to red indicating an increase in displacement) that during the pushing and pulling deformation process of the gripper 2 of the present invention, the highly reflective coating surface of the fused silica cylinder 11, i.e., the reflective surface 11a, moves uniformly and has the same displacement, and the annular groove bottom 13 does not show bending or torsion phenomena, indicating that the present invention meets the actual requirements of the laser gyro and will not have bending or torsion problems. This shows that this embodiment overcomes problems such as uneven thickness of the annular groove bottom and easy leakage of fused silica glass, eliminates bending and torsion in the path length scanning, can effectively improve the axial deformation range in the groove piece, and has high sensitivity and high stability, thus improving the overall performance of the gyro.

[0038] The above embodiments are only used to illustrate the present invention and are not intended to limit the present invention. Those of ordinary skill in the relevant technical field can also make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, all equivalent technical solutions also belong to the protection scope of the present invention.

Claims

1. A combined grooved sheet of a laser gyro based on an optical cementing process, comprising an annular groove bottom (13), characterized in that It also includes a glass-ceramic ring (12) and a fused silica cylinder (11); The glass-ceramic ring (12) is in a circular ring structure and is prepared from glass-ceramic. Its outer diameter is the diameter D1 of the combined grooved wafer of the laser gyro based on the optical cementing process, and the outer diameter D1 ≤ the side length of the bonding surface (4a) of the laser gyro cavity. The inner diameter D2 of the glass-ceramic ring (12) < D1, the thickness of the glass-ceramic ring (12) is H. The upper and lower end faces of the glass-ceramic ring (12) are polished into parallel planes to form polished planes that can be optically cemented. A fused silica cylinder (11) is coaxially nested inside the glass-ceramic ring (12); The fused silica cylinder (11) is cylindrical, with a height equal to H. The diameter d of the fused silica cylinder (11) < D2. The lower surface of the fused silica cylinder (11) is a polished plane that can be optically cemented, and the upper surface, i.e., the reflecting surface (11a), is a super-smooth high-reflectivity coated surface. The fused silica cylinder (11) is coaxially nested inside the glass-ceramic ring (12); the reflecting surface (11a) is a concave spherical surface, a convex spherical surface or a plane, and a high-reflection film is coated on the reflecting surface; The annular groove bottom (13) uses a glass-ceramic double-sided polished thin sheet, with an appearance of a disc shape, and is prepared from glass-ceramic. It is coaxially placed under the glass-ceramic ring (12) and the fused silica cylinder (11). Both the upper surface and the lower surface are polished, and the upper surface is optically cemented to the lower surface of the glass-ceramic ring (12) and the lower surface of the fused silica cylinder (11); the outer diameter D3 of the annular groove bottom (13) satisfies D2 < D3 ≤ D1, and the thickness h is 0.1 - 5 mm; the annular groove bottom (13) deforms under the action of the axial ejector pin (23) generated by the inverse piezoelectric effect of the clamping (2) piezoelectric ceramic, generating a micron-scale displacement change along the OO' axis.

2. The combined grooved chip of the laser gyroscope based on the photoresist process according to claim 1, characterized in that The D1 is 6 - 30 mm, the D2 = D1 - 2 - 10 mm, and the H is 1 - 8 mm; when the upper and lower end faces of the glass-ceramic ring (12) are polished into parallel planes, the required number of fringes ≤ 0.5, the local number of fringes ≤ 0.3, and the roughness ≤ 1 nm.

3. The combined grooved sheet of the laser gyroscope based on the photoresist process according to claim 1, characterized in that The diameter d of the fused silica cylinder (11) < D2 - 0.01 mm, the super-smooth means the roughness ≤ 0.1 nm; the reflectivity of the high-reflection film ≥ 99%.

4. The combined grooved sheet of the laser gyroscope based on the photoresist process according to claim 1, wherein The fused silica cylinder (11) adopts a glass-ceramic and fused silica glass composite structure, that is, part of the cylinder is made of glass-ceramic and part of the cylinder is made of fused silica glass. The two are combined into one by coaxial optical cementing. The glass-ceramic cylinder is at the bottom and the fused silica glass cylinder is at the top. The total height of the two parts is equal to H, and the upper surface of the fused silica cylinder (11) is used as the reflecting surface (11a).

5. The combined grooved wafer of a laser gyroscope based on a photoresist process according to claim 1, characterized in that After the annular groove bottom (13) is double-sided polished, any one of the processes of chemical etching, ion beam etching, and laser etching is used to reduce h to less than 0.1 mm, improving the axial deformation range in the grooved wafer.

6. The combined grooved sheet of the laser gyroscope based on the photoresist process according to claim 1, wherein The glass-ceramic used for the glass-ceramic ring (12), the fused silica cylinder (11), and the annular groove bottom (13) is the same as the glass-ceramic used for the laser gyro cavity to be assembled.

7. The combined grooved sheet of the laser gyroscope based on the photoresist process according to claim 1, characterized in that The glass-ceramic ring (12) is directly processed into a boss at the optical cementing surface (4a) of the laser gyro cavity by mechanical milling. The height of the boss is equal to H. After the fused silica glass cylinder 11 is optically cemented at the center of the bottom of the annular groove (13), the bottom of the annular groove (13) is directly optically cemented onto the boss optical cementing surface 4a of the laser gyro cavity with the boss, forming a combined groove slice of the laser gyro based on the optical cementing process.

8. The combined groove plate of the laser gyroscope based on the photoresist process according to claim 1, wherein A circular counterbore (12b) with a diameter of D4 is machined on the optical cementing surface where the glass-ceramic ring (12) is bonded to the bottom of the annular groove (13), satisfying D2 < D4 < D1, and the depth of the circular counterbore (12b) is 1μm < h2 < h.

9. The combined groove sheet of the laser gyroscope based on the photoresist process according to claim 1, characterized in that The fused silica cylinder (11) and the bottom of the annular groove (13) are connected into one body by means of deep optical cementing. The glass-ceramic ring (12) and the bottom of the annular groove (13) are combined by ordinary optical cementing. The bottom of the annular groove (13) is below and the glass-ceramic ring (12) is above.

10. The combined grooved wafer of a laser gyroscope based on a photoresist process according to claim 1, characterized in that The distance from the cementing surface (4a) of the gyro cavity (4) of the laser gyro equipped with the combined groove slice of the laser gyro based on the optical cementing process to the intersection point of the centers of the two optical path holes in the gyro cavity (4) is required to be equal to H.

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