Auxiliary cavity adjusting device for laser gyroscope

Abstract

The utility model discloses an auxiliary cavity adjusting device for a laser gyroscope, which comprises a He-Ne laser, a collimation laser, an adjustable first reflecting mirror, a semi-transparent semi-reflecting mirror, a second reflecting mirror, a third reflecting mirror, an imaging mechanism and a light beam coincidence verification structure, and is characterized in that the collimation laser is arranged on the right side of a cavity to be adjusted and corresponds to a left upper plane mirror of the cavity to be adjusted; the first reflecting mirror and the third reflecting mirror are located between the cavity to be adjusted and the collimating laser, the semi-transparent and semi-reflecting mirror is located between the second reflecting mirror and the He-Ne laser, the light beam coincidence verification structure is movably located between the semi-transparent and semi-reflecting mirror and the second reflecting mirror, the He-Ne laser is located right above the collimating laser, and the He-Ne laser is located right above the collimating laser. The semi-transparent semi-reflecting mirror is located over the first reflecting mirror, the second reflecting mirror is located over the third reflecting mirror, and the imaging mechanism is located on the right side of the cavity to be adjusted and corresponds to a left lower plane mirror of the cavity to be adjusted. According to the utility model, the cavity adjusting efficiency and accuracy of the laser gyroscope can be improved.

Description

Technical Field

[0001] This utility model relates to the field of laser gyroscope manufacturing technology, specifically to a laser gyroscope auxiliary cavity adjustment device. Background Technology

[0002] Laser gyroscopes are sensors based on the Sagnac effect optical principle. They are high-precision inertial sensitive instruments. Due to their advantages such as high reliability, stable performance, good environmental adaptability, and strong shock resistance, laser gyroscopes are widely used in aerospace, aviation, missile and other fields.

[0003] Due to manufacturing errors, there are differences between the reflecting mirrors. The orientation of the reflecting mirrors needs to be adjusted to maximize the mode volume and minimize the loss of the laser within the resonant cavity; this is known as cavity tuning in laser gyroscopes. For example... Figure 1 As shown, the laser gyroscope has four mirrors, of which M1 and M4 are semi-transparent and semi-reflective plane mirrors, and M2 and M3 are spherical mirrors. The reference laser enters the resonant cavity through the plane mirror M1 along the capillary axis, is reflected by the spherical mirror M2 to the spherical mirror M3, is reflected again to the plane mirror M4, and then returns to the plane mirror M1 to continue the next cycle.

[0004] During the cavity adjustment process, the relative positions of the aperture and the beam inside the cavity are detected by observing the shape of the light spot that the transmitted light emitted from the plane mirror M4 illuminates on the CCD camera, thereby determining whether the spherical mirrors M2 and M3 have reached the optimal position.

[0005] Cavity tuning typically uses a 632.8nm He-Ne laser as a reference laser. However, the reflector has very low transmittance for the 632.8nm He-Ne laser, resulting in weak transmitted light power and a blurred spot on the CCD camera after exiting from the plane mirror M4, which is not conducive to cavity tuning observation. Utility Model Content

[0006] To address the problems in the background art, this utility model proposes a laser gyroscope auxiliary cavity adjustment device to improve the cavity adjustment efficiency and accuracy of laser gyroscopes.

[0007] The present invention adopts the following technical solution:

[0008] A laser gyroscope-assisted cavity adjustment device includes a He-Ne laser, a collimating laser, a first reflecting mirror, a semi-transparent semi-reflective mirror, a second reflecting mirror, a third reflecting mirror, an imaging mechanism, and a beam coincidence verification structure.

[0009] The collimating laser is located on the right side of the cavity to be adjusted and corresponds to the upper left plane mirror of the cavity to be adjusted. The first and third reflecting mirrors are located between the cavity to be adjusted and the collimating laser. The semi-transparent semi-reflective mirror is located between the second reflecting mirror and the He-Ne laser. The beam coincidence verification structure is movably located between the semi-transparent semi-reflective mirror and the second reflecting mirror. The He-Ne laser is located directly above the collimating laser. The semi-transparent semi-reflective mirror is located directly above the first reflecting mirror. The second reflecting mirror is located directly above the third reflecting mirror. The imaging mechanism is located on the right side of the cavity to be adjusted and corresponds to the lower left plane mirror of the cavity to be adjusted.

[0010] The angles between the first and third reflecting mirrors relative to the laser beam emitted by the collimating laser are adjustable. The angles between the second and third reflecting mirrors relative to the laser beam emitted by the He-Ne laser are also adjustable. The angles between the first reflecting mirror, the semi-transparent semi-reflective mirror, the second reflecting mirror, and the third reflecting mirror relative to the mounting plane are also adjustable.

[0011] The He-Ne laser, a semi-transparent mirror, and a beam coincidence verification structure constitute the He-Ne optical path structure, while the collimating laser, a first reflecting mirror, a semi-transparent mirror, and a beam coincidence verification structure constitute the collimating optical path structure.

[0012] The collimated laser, the first reflecting mirror, the semi-transparent semi-reflecting mirror, the second reflecting mirror, the third reflecting mirror, the resonant cavity of the cavity to be adjusted, and the imaging mechanism constitute the coarse adjustment optical path structure, while the He-Ne laser, the semi-transparent semi-reflecting mirror, the second reflecting mirror, the third reflecting mirror, the resonant cavity of the cavity to be adjusted, and the imaging mechanism constitute the fine adjustment optical path structure.

[0013] Optionally, the beam coincidence verification structure is a CCD camera or an aperture.

[0014] Optionally, the imaging mechanism is a CCD camera.

[0015] Optionally, the wavelength of the laser emitted by the He-Ne laser is 632.8 nm.

[0016] Optionally, the wavelength of the laser emitted by the collimated laser is 520 nm.

[0017] Compared with the prior art, the advantages of this utility model are:

[0018] This invention relates to a laser gyroscope-assisted cavity tuning device. First, by adjusting the first reflecting mirror and the semi-transparent semi-reflective mirror, the beams of the He-Ne optical path structure and the collimated optical path structure are aligned via a beam alignment verification structure. Then, the beam alignment verification structure is removed, and the second and third reflecting mirrors are adjusted so that the aligned He-Ne beam and the collimated beam are incident along the optical axis of the resonant cavity into the resonant cavity to be tuned. Next, the He-Ne laser is turned off, and the coarse adjustment optical path structure is used to coarsely tune the cavity. The optimal and clearest collimated laser spot can be observed on the imaging mechanism, marking the end of the coarse adjustment. Then, the collimated laser is turned off, the He-Ne laser is turned on, and the fine adjustment optical path structure is used to finely tune the cavity. The optimal and clearest He-Ne laser spot can be observed on the imaging mechanism, marking the end of the fine adjustment. Therefore, this invention can achieve cavity adjustment of a laser gyroscope by combining a collimated laser coarse adjustment cavity with a He-Ne laser fine adjustment cavity, avoiding the problem of weak He-Ne transmitted light power which is not conducive to cavity adjustment observation, while also ensuring the accuracy of He-Ne laser cavity adjustment. Furthermore, this invention is low in cost, convenient, quick, and simple to operate, and greatly improves the cavity adjustment efficiency of the laser gyroscope. Attached Figure Description

[0019] To facilitate understanding of this invention, it will be described in more detail with reference to the specific embodiments shown in the accompanying drawings. These drawings depict only typical embodiments of this invention and should not be considered as limiting the scope of protection of this invention.

[0020] Figure 1 This is a schematic diagram of the cavity tuning of a laser gyroscope in the prior art.

[0021] Figure 2 This is a schematic diagram of the structure of the laser gyroscope auxiliary cavity adjustment device according to an embodiment of the present invention.

[0022] Figure 3 This is a schematic diagram of the structure of the cavity to be adjusted. Detailed Implementation

[0023] The embodiments of the present invention are described below with reference to the accompanying drawings, so that those skilled in the art can better understand and implement the present invention. However, the listed embodiments are not intended to limit the present invention. In the absence of conflict, the following embodiments and the technical features in the embodiments can be combined with each other, wherein the same components are indicated by the same reference numerals.

[0024] like Figure 2 As shown, this embodiment provides a laser gyroscope-assisted cavity adjustment device, including a He-Ne laser 1, a collimating laser 2, a first reflecting mirror 3, a semi-transparent and semi-reflective mirror 4, a second reflecting mirror 5, a third reflecting mirror 6, an imaging mechanism 8, and a beam coincidence verification structure 9.

[0025] The collimating laser 2 is located on the right side of the cavity 7 to be adjusted and corresponds to the upper left plane mirror of the cavity 7 to be adjusted. The first reflecting mirror 3 and the third reflecting mirror 6 are located between the cavity 7 to be adjusted and the collimating laser 2. The semi-transparent semi-reflecting mirror 4 is located between the second reflecting mirror 5 and the He-Ne laser 1. The beam coincidence verification structure 9 is movably located between the semi-transparent semi-reflecting mirror 4 and the second reflecting mirror 5. The He-Ne laser 1 is located directly above the collimating laser 2. The semi-transparent semi-reflecting mirror 4 is located directly above the first reflecting mirror 3. The second reflecting mirror 5 is located directly above the third reflecting mirror 6. The imaging mechanism 8 is located on the right side of the cavity 7 to be adjusted and corresponds to the lower left plane mirror of the cavity 7 to be adjusted.

[0026] The angles between the first reflector 3 and the third reflector 6 relative to the laser beam emitted by the collimating laser 2 are adjustable. The angles between the second reflector 5 and the third reflector 6 relative to the laser beam emitted by the He-Ne laser 1 are also adjustable. The angles between the first reflector 3, the semi-transparent semi-reflective mirror 4, the second reflector 5, and the third reflector 6 relative to the mounting plane are also adjustable.

[0027] The He-Ne laser 1, the semi-transparent mirror 4, and the beam coincidence verification structure 9 constitute the He-Ne optical path structure, while the collimating laser 2, the first mirror 3, the semi-transparent mirror 4, and the beam coincidence verification structure 9 constitute the collimating optical path structure.

[0028] The collimating laser 2, the first reflecting mirror 3, the semi-transparent semi-reflecting mirror 4, the second reflecting mirror 5, the third reflecting mirror 6, the resonant cavity of the cavity to be adjusted 7, and the imaging mechanism 8 form a coarse-tuning optical path structure, while the He-Ne laser 1, the semi-transparent semi-reflecting mirror 4, the second reflecting mirror 5, the third reflecting mirror 6, the resonant cavity of the cavity to be adjusted 7, and the imaging mechanism 8 form a fine-tuning optical path structure.

[0029] Therefore, by first adjusting the first reflecting mirror 3 and the semi-transparent semi-reflecting mirror 4, the beams of the He-Ne optical path structure and the collimated optical path structure can be aligned via the beam alignment verification structure 9. Then, the beam alignment verification structure 9 is removed, and the second reflecting mirror 5 and the third reflecting mirror 6 are adjusted so that the aligned He-Ne beam and the collimated beam are incident on the resonant cavity of the cavity to be adjusted 7 along the optical axis of the resonant cavity. Then, the He-Ne laser 1 is turned off, and the coarse adjustment optical path structure is used to coarsely adjust the cavity to be adjusted 7. The optimal and clearest collimated laser spot can be observed on the imaging mechanism 8, and the coarse adjustment is completed. Then, the collimated laser is turned off, the He-Ne laser is turned on, and the fine adjustment optical path structure is used to finely adjust the cavity to be adjusted 7. The optimal and clearest He-Ne laser spot can be observed on the imaging mechanism 8, and the fine adjustment is completed. Therefore, this invention can achieve cavity adjustment of a laser gyroscope by combining a collimated laser coarse adjustment cavity with a He-Ne laser fine adjustment cavity, avoiding the problem of weak He-Ne transmitted light power which is not conducive to cavity adjustment observation, while also ensuring the accuracy of He-Ne laser cavity adjustment. Furthermore, this invention is low in cost, convenient, quick, and simple to operate, and greatly improves the cavity adjustment efficiency of the laser gyroscope.

[0030] In this embodiment, the beam coincidence verification structure 9 is a CCD camera or an aperture.

[0031] In this embodiment, the imaging mechanism 8 is a CCD camera.

[0032] In this embodiment, the wavelength of the laser emitted by the He-Ne laser 1 is 632.8 nm.

[0033] In this embodiment, the wavelength of the laser emitted by the collimated laser 2 is 520nm.

[0034] The process of using the device of this embodiment to assist in the cavity adjustment of a laser gyroscope is as follows:

[0035] S1. Turn on He-Ne laser 1 and collimating laser 2. The He-Ne laser emitted by He-Ne laser 1 with a wavelength of 632.8nm is transmitted through the semi-transparent mirror 4 and then shines on the first CCD camera (i.e., beam coincidence verification structure 9). The collimated laser emitted by collimating laser 2 with a wavelength of 520nm is reflected by the first mirror 3 and the semi-transparent mirror 4 and then shines on the first CCD camera (i.e., beam coincidence verification structure 9). First, place the first CCD camera close to the semi-transparent mirror 4, and adjust the angles of the first mirror 3 and the semi-transparent mirror 4 so that the He-Ne laser spot illuminating the first CCD camera coincides with the collimated laser spot; then, place the first CCD camera away from the semi-transparent mirror 4, and continue to adjust the angles of the first mirror 3 and the semi-transparent mirror 4 so that the He-Ne laser spot illuminating the first CCD camera coincides with the collimated laser spot; repeatedly move the first CCD camera and adjust the angles of the first mirror 3 and the semi-transparent mirror 4 several times until the He-Ne laser and the collimated laser beam path are completely aligned.

[0036] S2. Remove the first CCD camera, adjust the second reflector 5 and the third reflector 6 so that the combined beam of the He-Ne laser and the collimated laser is reflected by the second reflector 5 and the third reflector 6 respectively, and then enters the resonant cavity of the laser gyroscope 7 from the first plane reflector 71. The emitted light spot is observed using the second CCD camera (i.e., imaging mechanism 8) mounted on the other end of the second plane reflector 74 of the laser gyroscope cavity 7.

[0037] S3. Turn off the He-Ne laser, adjust the first slot plate 72 and the second slot plate 73 on the cavity to be tuned 7 so that a clear optimal collimated laser spot can be observed on the second CCD camera, and keep the positions of the first slot plate 72 and the second slot plate 73 unchanged.

[0038] S4. Turn off the collimating laser, turn on the He-Ne laser, and fine-tune the first slot 72 and the second slot 73 so that a clear and optimal He-Ne laser spot can be observed on the second CCD camera. Keep the positions of the first slot 72 and the second slot 73 fixed and apply optical adhesive.

[0039] The embodiments described above are merely preferred embodiments of this utility model. The terms "in one embodiment," "in another embodiment," "in yet another embodiment," or "in still another embodiment" used in this specification all refer to one or more of the same or different embodiments according to this disclosure. Ordinary variations and substitutions made by those skilled in the art within the scope of this utility model's technical solution should be included within the protection scope of this utility model.

Claims

1. A laser gyroscope-assisted cavity adjustment device, characterized in that, It includes a He-Ne laser (1), a collimating laser (2), a first reflector (3), a semi-transparent and semi-reflective mirror (4), a second reflector (5), a third reflector (6), an imaging mechanism (8), and a beam coincidence verification structure (9). The collimating laser (2) is located on the right side of the cavity to be adjusted (7) and corresponds to the upper left plane mirror of the cavity to be adjusted (7). The first reflector (3) and the third reflector (6) are located between the cavity to be adjusted (7) and the collimating laser (2). The semi-transparent semi-reflecting mirror (4) is located between the second reflector (5) and the He-Ne laser (1). The beam coincidence verification structure (9) is movably located between the semi-transparent semi-reflecting mirror (4) and the second reflector (5). The He-Ne laser (1) is located directly above the collimating laser (2). The semi-transparent semi-reflecting mirror (4) is located directly above the first reflector (3). The second reflector (5) is located directly above the third reflector (6). The imaging mechanism (8) is located on the right side of the cavity to be adjusted (7) and corresponds to the lower left plane mirror of the cavity to be adjusted (7). The angles between the first reflector (3) and the third reflector (6) relative to the laser beam emitted by the collimating laser (2) are adjustable. The angles between the second reflector (5) and the third reflector (6) relative to the laser beam emitted by the He-Ne laser (1) are adjustable. The angles between the first reflector (3), the semi-transparent semi-reflective mirror (4), the second reflector (5), and the third reflector (6) relative to the mounting plane are adjustable. The He-Ne laser (1), the semi-transparent mirror (4), and the beam coincidence verification structure (9) constitute the He-Ne optical path structure, and the collimating laser (2), the first mirror (3), the semi-transparent mirror (4), and the beam coincidence verification structure (9) constitute the collimating optical path structure. The collimated laser (2), the first reflector (3), the semi-transparent and semi-reflective mirror (4), the second reflector (5), the third reflector (6), the resonant cavity of the cavity to be adjusted (7), and the imaging mechanism (8) form a coarse-tuning optical path structure. The He-Ne laser (1), the semi-transparent and semi-reflective mirror (4), the second reflector (5), the third reflector (6), the resonant cavity of the cavity to be adjusted (7), and the imaging mechanism (8) form a fine-tuning optical path structure.

2. The laser gyroscope-assisted cavity adjustment device according to claim 1, characterized in that, The beam coincidence verification structure (9) is a CCD camera or an aperture.

3. The laser gyroscope-assisted cavity adjustment device according to claim 1, characterized in that, The imaging mechanism (8) is a CCD camera.

4. The laser gyroscope-assisted cavity adjustment device according to claim 1, characterized in that, The wavelength of the laser emitted by the He-Ne laser (1) is 632.8 nm.

5. The laser gyroscope-assisted cavity adjustment device according to claim 1, characterized in that, The wavelength of the laser emitted by the collimated laser (2) is 520nm.

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