A solid-state active laser gyroscope and its measurement method

Abstract

This application discloses an all-solid-state active laser gyroscope and its measurement method. The technical solution provided by this application uses a millimeter-scale single non-planar ring cavity as the resonant cavity, which has a compact structure and advantages such as structural stability and minimal influence from external environmental factors such as air pressure and temperature. Compared with the disadvantages of existing helium-neon gas laser gyroscopes, which are large in size and difficult to integrate, the laser crystal used in this gyroscope is only on the millimeter scale, which can achieve miniaturized integration and assembly. Moreover, it can avoid the lock-up effect without using complex technical solutions such as mechanical dithering or four-frequency differential, and can achieve measurement of low speed.

Description

Technical Field

[0001] This application relates to the field of laser gyroscope technology, and in particular to an all-solid-state active laser gyroscope and its measurement method. Background Technology

[0002] Ring laser gyroscopes (RLGs) are the main representatives of optical gyroscopes, and they are divided into two main categories based on their operating modes: active RLGs and passive RLGs. The core difference between the two lies in the position of the light source. Active RLGs are themselves lasers, typically helium-neon gas lasers. They are filled with helium-neon gas and achieve dual-mode (or multi-mode) laser resonance output under high-voltage or radio-frequency excitation conditions. The rotation signal is ultimately obtained by detecting the beat frequency between different modes. Passive RLGs have their light source located outside the ring resonator. After injecting laser light into the high-quality ring resonator cavity, the rotation signal is obtained by detecting the phase difference of the laser light in different propagation directions.

[0003] Traditional active helium-neon resonant gyroscopes (RLGs) have achieved great success in inertial navigation, inertial measurement, and attitude and heading reference. However, the gas gain medium, vacuum tube, high-voltage discharge circuit, and bulky optical components they use have hindered further reductions in size, weight, power, and cost. Furthermore, the unique structure of the resonant cavity makes the gyroscope relatively heavy, resulting in high material and manufacturing costs. Summary of the Invention

[0004] This application provides an all-solid-state active laser gyroscope and a measurement method to solve the technical problem that existing laser gyroscopes are bulky and have high material and processing costs due to the special structure of the resonant cavity.

[0005] To address the aforementioned technical problems, the first aspect of this application provides an all-solid-state active laser gyroscope, comprising: a pump laser module, a beam splitter, a signal processing module, a monolithic non-planar ring cavity crystal, a magnet unit, and a reflector, wherein the magnet unit is used to apply a directional magnetic field to the monolithic non-planar ring cavity crystal;

[0006] The pump laser module is connected to the beam splitter via an optical path. The first splitting port of the beam splitter is connected to the optical path of the single non-planar ring cavity crystal, and the second splitting port is connected to the optical path of the signal processing module.

[0007] The laser output from the first branch port enters from the first plane of the monolithic non-planar ring cavity crystal, and after reflection inside the monolithic non-planar ring cavity crystal, it exits from the first plane to the reflector, so as to reflect the original path of the light output from the monolithic non-planar ring cavity crystal through the reflector.

[0008] Preferably, the pump laser module includes: a pump laser diode, an optical fiber, and a coupling lens.

[0009] Preferably, the pump laser diode is connected to the coupling lens optical path via an optical fiber, and the coupling lens is used for optical path connection of the optical path input port of the beam splitter.

[0010] Preferably, the signal processing module includes: a photodetector and a measuring device;

[0011] The photodetector is used to receive the laser signal output from the second splitter port of the beam splitter, convert the laser signal into an analog circuit signal, and send the analog circuit signal to the measuring device.

[0012] Preferably, the measuring device includes a spectrum analyzer and a frequency counter.

[0013] Preferably, the first plane of the single non-planar annular cavity crystal serves as the incident and exit planes;

[0014] The second to fourth planes are total reflection surfaces, used to reflect the laser light after it enters from the first plane of the monolithic non-planar ring cavity crystal, through the reflection of the three reflecting surfaces inside the monolithic non-planar ring cavity crystal, forming an intracavity optical path and exiting again from the first plane, wherein the intracavity optical path is not on the same plane.

[0015] Preferably, the incident surface of the first plane is coated with a pump antireflection film, and the exit surface is coated with a stimulated emission high reflectivity film.

[0016] The second aspect of this application provides a laser gyroscope signal measurement method, applied to an all-solid-state active laser gyroscope as provided in the first aspect of this application, comprising:

[0017] The laser signal is acquired through the signal processing module and converted into the corresponding analog circuit signal through photoelectric conversion.

[0018] Sending the analog circuit signal into the measuring device includes: a spectrum analyzer and a frequency counter;

[0019] A spectrum analyzer records the spectral information of analog circuit signals, while a frequency counter records the frequency information of analog circuit signals.

[0020] By using a beat frequency signal relationship model, it can be determined that the analog circuit signals contain information about beat frequency signals.

[0021] Based on the characteristics of the beat frequency signal and the relationship between frequency change and rotational angular velocity, the gyroscope rotation data is determined.

[0022] Preferably, the beat frequency signal relationship model is as follows:

[0023]

[0024] In the formula, These are the light intensities in the CW and CCW directions after feedback. The values ​​represent the light intensities in the CW and CCW directions before feedback, and r represents the stimulated emission ratio of the laser mode. The sum of intracavity losses for the two modes in both directions, Losses introduced by self-feedback For CW direction frequency, The photon flight time from a single non-planar ring-cavity crystal to a mirror and then back to a single non-planar ring-cavity crystal. This refers to the beat frequency signal carried on the optical path.

[0025] Preferably, the relationship between the frequency change and the rotational angular velocity is as follows:

[0026]

[0027] In the formula, Indicates the change in frequency. The projected area of ​​the intracavity optical loop formed by the single non-planar ring cavity crystal is given. Let be the perimeter of the intracavity optical loop of the single non-planar annular cavity crystal. The wavelength of light The value is the rotational speed.

[0028] As can be seen from the above technical solutions, this application has the following advantages:

[0029] The technical solution provided in this application uses a millimeter-scale single non-planar ring cavity as the resonant cavity. It has a compact structure and advantages such as structural stability and minimal influence from external factors such as air pressure and temperature. Compared with the disadvantages of existing helium-neon gas laser gyroscopes, which are large in size and difficult to integrate, the laser crystal used in this gyroscope is only on the millimeter scale, which can achieve miniaturized integration and assembly. Moreover, it can avoid the lock-up effect without using complex technical solutions such as mechanical dithering or four-frequency differential, and can achieve measurement of low speed. Attached Figure Description

[0030] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0031] Figure 1 This is a schematic diagram of the structure of an all-solid-state active laser gyroscope provided in this application.

[0032] Figure 2 This is a schematic diagram of the structure of a single non-planar ring cavity crystal in an all-solid-state active laser gyroscope provided in this application.

[0033] Figure 3 The image shows the spectrum of the bidirectional beam beat frequency signal obtained from an all-solid-state active laser gyroscope provided in this application.

[0034] Figure 4 The graph shows the relationship between gyroscope rotation speed and frequency shift based on an all-solid-state active laser gyroscope provided in this application.

[0035] Figure 5 This is a frequency noise diagram of the beat frequency signal obtained based on an all-solid-state active laser gyroscope provided in this application.

[0036] Figure 6 The image shows the Allen deviation of the beat frequency signal frequency noise obtained based on an all-solid-state active laser gyroscope provided in this application.

[0037] The reference numerals in the figure include:

[0038] 1. Pump laser diode, 2. Optical fiber, 3. Coupler lens, 4. Beam splitter, 5. Photodetector, 6. Monolithic non-planar ring cavity crystal, 7. Magnet unit, 8. Semiconductor cooler, 9. Mirror, 10. Spectrum analyzer, 11. Frequency counter. Detailed Implementation

[0039] This application provides an all-solid-state active laser gyroscope and a measurement method to solve the technical problem that existing laser gyroscopes are bulky and have high material and processing costs due to the special structure of the resonant cavity.

[0040] To make the inventive objectives, features, and advantages of this application more apparent and understandable, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described below are only a part of the embodiments of this application, and not all of them. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0041] First, a detailed description of an embodiment of an all-solid-state active laser gyroscope device provided in this application is as follows:

[0042] Please see Figure 1The first aspect of this application provides an all-solid-state active laser gyroscope, comprising: a pump laser module, a beam splitter 4, a signal processing module, a monolithic non-planar ring cavity crystal 6, a magnet unit 7, and a reflector, wherein the magnet unit 7 is used to apply a directional magnetic field to the monolithic non-planar ring cavity crystal;

[0043] The pump laser module is connected to the beam splitter via an optical path. The first splitting port of the beam splitter is connected to the optical path of the single non-planar ring cavity crystal, and the second splitting port is connected to the optical path of the signal processing module. The beam splitter can be a beam splitter 4.

[0044] The laser output from the first branch port enters from the first plane of the monolithic non-planar ring cavity crystal, and after reflection inside the monolithic non-planar ring cavity crystal, it exits from the first plane to the reflector, so as to reflect the original path of the light output from the monolithic non-planar ring cavity crystal through the reflector.

[0045] Furthermore, the pump laser module includes: a pump laser diode 1, an optical fiber 2, and a coupling lens 3;

[0046] The pump laser emitted by the pump laser diode 1 is connected to the coupling lens 3 via the optical fiber 2. The coupling lens 3 is used for the optical path connection of the optical path input port of the beam splitter.

[0047] Furthermore, the signal processing module includes: a photodetector 5 and a measuring device;

[0048] The photodetector 5 is used to receive the laser signal output from the second split port of the beam splitter, convert the laser signal into an analog circuit signal, and send the analog circuit signal to the measuring device.

[0049] Furthermore, the measuring device includes a spectrum analyzer 10 and a frequency counter 11.

[0050] Furthermore, the first plane of the single non-planar annular cavity crystal 6 serves as the incident and exit planes;

[0051] The second to fourth planes are total reflection surfaces, used to reflect the laser light after it enters from the first plane of the monolithic non-planar ring cavity crystal 6, through the reflection of the three reflecting surfaces inside the monolithic non-planar ring cavity crystal, forming an intracavity optical path and exiting again from the first plane, wherein the intracavity optical path is not on the same plane.

[0052] Furthermore, the incident surface of the first plane is coated with a pump antireflection film, and the exit surface is coated with a stimulated emission high reflectivity film.

[0053] It should be noted that the specific structure of the all-solid-state active laser gyroscope provided in this embodiment is as follows: Figure 1 As shown, the system includes: a pump laser diode 1, an optical fiber 2, a coupling lens 3, a beam splitter 4, a photodetector 5, a monolithic non-planar ring cavity crystal 6, a magnet unit 7, a semiconductor cooler 8, a reflector 9, a spectrum analyzer 10, and a frequency counter 11. The magnet unit 7 can be a permanent magnet, an electromagnetic solenoid, or a combination of a permanent magnet and an electromagnetic solenoid. When using an electromagnetic solenoid, a driving power supply is required. The pump laser diode can be in spatial beam form, in which case an optical fiber is not needed; the pump light can be directly injected into the monolithic non-planar ring cavity crystal 6 through the coupling lens 3 and the beam splitter 4. The main body material of the monolithic non-planar ring cavity crystal 6 can be crystal, glass, or other composite (bonded) materials. The measuring equipment includes, but is not limited to, the spectrum analyzer 10 and the frequency counter 11; other devices or equipment capable of measuring beat frequency or phase can also be selected.

[0054] The implementation process of this embodiment is as follows: the pump laser diode 1 emits pump light, the wavelength parameter of which is preferably 808nm. The pump light is focused into the interior of a single non-planar ring cavity crystal 6 by the coupling lens 3. The single non-planar ring cavity crystal 6 used in this embodiment is an Nd:YAG crystal, but it can also be replaced with neodymium-doped glass, erbium-doped crystal or glass, thulium-doped crystal or glass, or other composite crystal or glass materials. The temperature of the single non-planar ring cavity crystal 6 is controlled by a semiconductor cooling chip 8. Under the action of the magnetic field of the magnet unit 7, the non-planar ring cavity crystal generates unstable bidirectional stimulated emission light (clockwise CW and counterclockwise CCW directions). At this time, the counterclockwise (CCW) stimulated emission light is reflected back into the cavity by the reflector 9, so that the bidirectional light output can be stably maintained. According to the intrinsic polarization theory of non-planar ring cavities, the modes of the two beams of light are not degenerate, and the frequency difference is related to the strength of the external magnetic field, which is usually from hundreds of kHz to several MHz. This is reflected in the photodetector 5 as a beat frequency signal of hundreds of kHz to several MHz. Since the annular optical path inside the crystal is closed, the stimulated emission light inside the crystal follows the Sagnac effect. When the device rotates, the beat frequency signal will shift accordingly, and the frequency shift is linearly related to the rotational angular velocity. Based on this property, it can be used as a laser gyroscope.

[0055] The working principle of a single non-planar ring cavity crystal is as follows: The non-planar ring cavity is a single-piece structure integrating a laser crystal and a non-planar ring cavity, such as... Figure 2As shown, the first plane A is the incident and exit plane, coated with a pump light antireflection film and a stimulated emission high-reflection film. The second plane B, the third plane C, and the fourth plane D are all total reflection surfaces. ABCD is the optical path within the cavity. A non-planar ring cavity specifically refers to a cavity where the optical paths ABCD are not on the same plane. According to the intrinsic polarization theory of non-planar ring cavities, when the pump light enters the crystal through a coupling lens and is absorbed by the cavity, converting it into the gain of stimulated emission light, four resonant modes of light beams are generated. Furthermore, the beams of different resonant modes have different losses and different frequency splits (compared to four times the degeneracy frequency). Under a certain magnetic field environment, the two clockwise (CW) and counterclockwise (CCW) beams with the smallest loss difference resonate, and the two resonant beams have specific frequency splits under the corresponding magnetic field. Then, through... Figure 1 The self-feedback interference phenomenon introduced by the middle reflector 9 causes CW photons and CCW photons to couple, resulting in the beat frequency signal relationship model shown below. Since the laser gyroscope in this embodiment utilizes the principle of self-feedback interferometry, clockwise and counterclockwise photons couple within the cavity, carrying each other's information. Therefore, beat frequency signal extraction can be achieved with only single-channel measurement and without beam combining.

[0056] The beat frequency signal relationship model is specifically as follows:

[0057]

[0058] In the formula, These are the light intensities in the CW and CCW directions after feedback. The values ​​represent the light intensities in the CW and CCW directions before feedback, and r represents the stimulated emission ratio of the laser mode. The sum of intracavity losses for the two modes in both directions, Losses introduced by self-feedback For CW direction frequency, The photon flight time from a single non-planar ring-cavity crystal to a mirror and then back to a single non-planar ring-cavity crystal. This refers to the beat frequency signal carried on the optical path.

[0059] The beat frequency signal relationship model formula shows that each optical path carries its own beat frequency information, thus enabling single-path measurement (measuring a single CW or CCW without needing to combine them) to extract the beat frequency signal. In this case, the typical morphology of the beat frequency signal is as follows: Figure 3 As shown.

[0060] Because the non-planar ring cavity optical path is as follows Figure 2 For the closed loop optical path shown, the formulas for frequency change and rotational angular velocity derived from the Sagnac effect are as follows:

[0061]

[0062] In the formula, Indicates the change in frequency. The projected area of ​​the intracavity optical loop formed by the single non-planar ring cavity crystal is given. Let be the perimeter of the intracavity optical loop of the single non-planar annular cavity crystal. The wavelength of light Based on Sagnac's principle, the relationship between the frequency shift and the rotational speed of this gyroscope was measured and plotted as follows: Figure 4 As shown in the figure, the scatter points represent the measured rotational speed values, and the solid line represents the fitted straight line, indicating a strong linear relationship between the measured values. To further demonstrate the gyroscope's performance, the frequency noise of the gyroscope's beat frequency signal is shown below. Figure 5 As shown, Figure 5 The corresponding Allen bias is as follows Figure 6 As shown, from Figure 6 As can be seen from the Allen bias, the zero bias instability (BI) of the laser gyroscope provided in this embodiment is... Angle Random Walk (ARW) is .

[0063] In the description of this application, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0064] Unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0065] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. A solid-state active laser gyroscope, characterized in that, The application relates to a laser gyroscope, which comprises a pump laser module, a light splitting device, a signal processing module, a single non-planar ring cavity crystal, a magnet unit for applying a directional magnetic field to the single non-planar ring cavity crystal, and a mirror. The pump laser module is connected with the light splitting device through an optical path, a first branch port of the light splitting device is connected with the single non-planar ring cavity crystal through an optical path, and a second branch port is connected with the signal processing module through an optical path. Laser output from the first branch port is emitted from a first plane of the single non-planar ring cavity crystal, is reflected inside the single non-planar ring cavity crystal, and is emitted from the first plane to the mirror, so that the light output from the single non-planar ring cavity crystal is reflected back through the mirror. The pump laser module comprises a pump laser diode, an optical fiber, and a coupling lens.

2. A solid-state ring laser gyroscope according to claim 1, wherein The pump laser diode is connected with the coupling lens through the optical fiber, and the coupling lens is connected with an optical path input port of the light splitting device.

3. A solid-state ring laser gyroscope according to claim 2, wherein The signal processing module comprises a photodetector and a measuring device.

4. A solid-state ring laser gyroscope according to claim 1, wherein The photodetector is used for receiving laser signals output from the second branch port of the light splitting device, converting the laser signals into analog circuit signals, and sending the analog circuit signals to the measuring device. The measuring device comprises a frequency counter and a spectrum analyzer.

5. A solid-state ring laser gyroscope according to claim 4, wherein The first plane of the single non-planar ring cavity crystal serves as an incident and emitting plane.

6. A solid-state ring laser gyroscope according to claim 1, wherein The second plane to the fourth plane are total reflection planes, which are used for reflecting laser emitted from the first plane of the single non-planar ring cavity crystal through three reflection planes inside the single non-planar ring cavity crystal, forming an intracavity optical path and emitting from the first plane again, wherein the intracavity optical path is not in the same plane. The incident plane of the first plane is coated with a pump anti-reflection film, and the emitting plane is coated with a high-reflection film of stimulated radiation light.

7. A solid-state ring laser gyroscope according to claim 6, wherein The application relates to a laser gyroscope, which comprises a pump laser module, a light splitting device, a signal processing module, a single non-planar ring cavity crystal, a magnet unit for applying a directional magnetic field to the single non-planar ring cavity crystal, and a mirror.

8. A method for measuring the signal of a laser gyro, applied to a full solid-state active laser gyro as claimed in any one of claims 1 to 7, characterized in that, The pump laser module is connected with the light splitting device through an optical path, a first branch port of the light splitting device is connected with the single non-planar ring cavity crystal through an optical path, and a second branch port is connected with the signal processing module through an optical path. Laser output from the first branch port is emitted from a first plane of the single non-planar ring cavity crystal, is reflected inside the single non-planar ring cavity crystal, and is emitted from the first plane to the mirror, so that the light output from the single non-planar ring cavity crystal is reflected back through the mirror. The pump laser module comprises a pump laser diode, an optical fiber, and a coupling lens. The pump laser diode is connected with the coupling lens through the optical fiber, and the coupling lens is connected with an optical path input port of the light splitting device. The signal processing module comprises a photodetector and a measuring device. The photodetector is used for receiving laser signals output from the second branch port of the light splitting device, converting the laser signals into analog circuit signals, and sending the analog circuit signals to the measuring device.

9. The laser gyro signal measurement method of claim 8 wherein, The measuring device comprises a frequency counter and a spectrum analyzer. wherein, Icwand Iccware the feedback post light intensity in the CW and CCW directions, respectively, Icw0and Iccw0are the feedback pre light intensity in the CW and CCW directions, respectively, and r is the stimulated emission ratio of the laser mode, are the intra-cavity losses of the modes in both directions, and is the loss introduced by the feedback, is the CW direction frequency, is the photon flight time from the monolithic non-planar ring laser crystal to the mirror and back to the monolithic non-planar ring laser crystal, is the beat frequency signal carried on the optical path.

10. The laser gyro signal measurement method of claim 8 wherein, The first plane of the single non-planar ring cavity crystal serves as an incident and emitting plane. The second plane to the fourth plane are total reflection planes, which are used for reflecting laser emitted from the first plane of the single non-planar ring cavity crystal through three reflection planes inside the single non-planar ring cavity crystal, forming an intracavity optical path and emitting from the first plane again, wherein the intracavity optical path is not in the same plane. The incident plane of the first plane is coated with a pump anti-reflection film, and the emitting plane is coated with a high-reflection film of stimulated radiation light. The application relates to a laser gyroscope, which comprises a pump laser module, a light splitting device, a signal processing module, a single non-planar ring cavity crystal, a magnet unit for applying a directional magnetic field to the single non-planar ring cavity crystal, and a mirror. The pump laser module is connected with the light splitting device through an optical path, a first branch port of the light splitting device is connected with the single non-planar ring cavity crystal through an optical path, and a second branch port is connected with the signal processing module through an optical path. Laser output from the first branch port is emitted from a first plane of the single non-planar ring cavity crystal, is reflected inside the single non-planar ring cavity crystal, and is emitted from the first plane to the mirror, so that the light output from the single non-planar ring cavity crystal is reflected back through the mirror. The pump laser module comprises a pump laser diode, an optical fiber, and a coupling lens. The pump laser diode is connected with the coupling lens through the optical fiber, and the coupling lens is connected with an optical path input port of the light splitting device. The signal processing module comprises a photodetector and a measuring device. The photodetector is used for receiving laser signals output from the second branch port of the light splitting device, converting the laser signals into analog circuit signals, and sending the analog circuit signals to the measuring device. The measuring device comprises a frequency counter and a spectrum analyzer. The first plane of the single non-planar ring cavity crystal serves as an incident and emitting plane. The second plane to the fourth plane are total reflection planes, which are used for reflecting laser emitted from the first plane of the single non-planar ring cavity crystal through three reflection planes inside the single non-planar ring cavity crystal, forming an intracavity optical path and emitting from the first plane again, wherein the intracavity optical path is not in the same plane. The incident plane of the first plane is coated with a pump anti-reflection film, and the emitting plane is coated with a high-reflection film of stimulated radiation light. The application relates to a laser gyroscope, which comprises a pump laser module, a light splitting device, a signal processing module, a single non-planar ring cavity crystal, a magnet unit for applying a directional magnetic field to the single non-planar ring cavity crystal, and a mirror. The pump laser module is connected with the light splitting device through an optical path, a first branch port of the light splitting device is connected with the single non-planar ring cavity crystal through an optical path, and a second branch port is connected with the signal processing module through an optical path. Laser output from the first branch port is emitted from a first plane of the single non-planar ring cavity crystal, is reflected inside the single non-planar ring cavity crystal, and is emitted from the first plane to the mirror, so that the light output from the single non-planar ring cavity crystal is reflected back through the mirror. The pump laser module comprises a pump laser diode, an optical fiber, and a coupling lens. The pump laser diode is connected with the coupling lens through the optical fiber, and the coupling lens is connected with an optical path input port of the light splitting device. The signal processing module comprises a photodetector and a measuring device. The photodetector is used for receiving laser signals output from the second branch port of the light splitting device, converting the laser signals into analog circuit signals, and sending the analog circuit signals to the measuring device. The measuring device comprises a frequency counter and a spectrum analyzer. The first plane of the single non-planar ring cavity crystal serves as an incident and emitting plane. The second plane to the fourth plane are total reflection planes, which are used for reflecting laser emitted from the first plane of the single non-planar ring cavity crystal through three reflection planes inside the single non-planar ring cavity crystal, forming an intracavity optical path and emitting from the first plane again, wherein the intracavity optical path is not in the same plane. The incident plane of the first plane is coated with a pump anti-reflection film, and the emitting plane is coated with a high-reflection film of stimulated radiation light. The application relates to a laser gyroscope, which comprises a pump laser module, a light splitting device, a signal processing module, a single non-planar ring cavity crystal, a magnet unit for applying a directional magnetic field to the single non-planar ring cavity crystal, and a mirror. The pump laser module is connected with the light splitting device through an optical path, a first branch port of the light splitting device is connected with the single non-planar ring cavity crystal through an optical path, and a second branch port is connected with the signal processing module through an optical path. Laser output from the first branch port is emitted from a first plane of the single non-planar ring cavity crystal, is reflected inside the single non-planar ring cavity crystal, and is emitted from the first plane to the mirror, so that the light output from the single non-planar ring cavity crystal is reflected back through the mirror. The pump laser module comprises a pump laser diode, an optical fiber, and a coupling lens. The pump laser diode is connected with the coupling lens through the optical fiber, and the coupling lens is connected with an optical path input port of the light splitting device. The signal processing module comprises a photodetector and a measuring device. The photodetector is used for receiving laser signals output from the second branch port of the light splitting device, converting the laser signals into analog circuit signals, and sending the analog circuit signals to the measuring device. The measuring device comprises In the formula, represents the frequency variation amount, is the projected area of the intracavity optical loop of the monolithic non-planar ring laser, is the circumference of the intracavity optical loop of the monolithic non-planar ring laser, is the optical wavelength, is the rotation speed.

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