Angular vibration measuring device and method based on compressed state light source

Abstract

The invention relates to the technical field of laser quantum interference measurement, in particular to an angular vibration measurement device and method based on a compressed state light source, which can measure high-frequency angular vibration parameters, the measurement result is expected to break through the standard quantum limit, and the measurement precision is effectively improved. The high-frequency angular vibration measurement device based on the compressed state light source is provided by combining the continuous variable compressed state quantum light source with linear interference measurement, measurement of high-frequency angular vibration parameters is achieved, the measurement result is expected to break through the standard quantum limit, and effective improvement of the measurement precision is achieved. The problem that in the traditional interference measurement process, the measurement result cannot break through the standard quantum limit is solved, and therefore high-sensitivity measurement is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of laser quantum interference measurement, and in particular to an angular vibration measurement device and method based on a compressed state light source. Background Art

[0002] Existing high-frequency angular vibration measurements usually use laser interferometry, that is, using a heterodyne laser interferometer in combination with a standard angular vibration table (capable of generating known angular vibration signals) to accurately measure high-frequency angular vibrations through the laser interference phenomenon. During measurement, a standard angular vibration table is used to generate a high-frequency angular vibration signal of known frequency and amplitude, and then a laser interferometer is used to measure the angular vibration signal parameters generated by the angular vibration table. The laser used in the measurement is a coherent laser. The current problem with this technical method is that in the field of high-precision measurement technology, the current measurement accuracy cannot meet the measurement requirements, and the measurement accuracy needs to be further improved. Summary of the invention

[0003] In view of this, the present invention provides an angular vibration measurement device and method based on a squeezed state light source, which can measure high-frequency angular vibration parameters. The measurement results are expected to break through the standard quantum limit and effectively improve the measurement accuracy.

[0004] To achieve the above purpose, the technical solution of the present invention is as follows:

[0005] An angular vibration measuring device based on a compressed state light source comprises a laser light source, a beam splitter, a continuous variable light source generating module, an MZ interference optical path, an optical fiber circulator and a standard vibration exciter;

[0006] The same laser light source generates coherent light and compressed light, wherein the continuous variable light source generating module generates compressed light; the coherent light and the compressed light are respectively injected into the MZ interference optical path from both ends of the beam splitter prism, and the reflected measurement light carrying angular vibration information is returned to the MZ interference optical path by using an optical fiber circulator, and the measurement light and the reference light are combined and interfered by the beam splitter to perform zero-beat balance detection; the standard vibration exciter is used to generate a standard mechanical vibration signal.

[0007] Specifically, it includes a laser light source, a first beam splitter prism, a second reflector, a third reflector, a continuous variable light source generation module, a second beam splitter prism, an acousto-optic frequency shifter, a fourth reflector, a fifth reflector, an optical fiber circulator, a first collimator, a second collimator, a third beam splitter prism, a first photodetector, a target mirror, a reference accelerometer, a standard vibration exciter, a second photodetector, a signal acquisition and processing device, a vibration controller and a computer;

[0008] The coherent light generated by the laser light source is divided into two laser beams after passing through the first beam splitter prism, wherein the transmitted laser beam is incident on the second reflector and reaches the second beam splitter prism after being reflected by the second reflector; the reflected laser beam is incident on the third reflector and enters the continuous variable light source generation module after being reflected by the third reflector to generate compressed light, and the compressed light is also sent to the second beam splitter prism; the two laser beams are combined and split on the second beam splitter prism, and after being transmitted and reflected by the second beam splitter prism, both the transmitted light and the reflected light contain coherent light and compressed light; one of the laser beams is frequency-shifted by the acousto-optic frequency shifter and reaches the fifth reflector; the other laser beam is incident on the fourth reflector and reaches the optical fiber circulator after being reflected by the fourth reflector; the optical signal is input from port ① of the optical fiber circulator and output from port ② in numerical order, and the laser signal output from port ② is incident on the target target mirror after passing through the first collimator; the target target mirror is fixed on a standard vibration exciter, and the standard vibration exciter generates a standard mechanical vibration signal under the control of a vibration controller, and the reference accelerometer and the target target mirror are used as reference accelerometers and target targets. The mirror is fixedly mounted on a standard vibration exciter; the output signal of the reference accelerometer is used as a feedback signal for vibration control, and the output electrical signal is fed back to the vibration controller, which receives the feedback signal from the reference accelerometer and performs calculation and solution according to a preset algorithm, thereby realizing precise control of the standard mechanical vibration signal; after the laser is reflected by the target mirror, the laser light signal carrying the angular vibration is incident into the optical fiber through the first collimator and transmitted to the port ② of the optical fiber circulator, and is output from the port ③; the laser signal output from the port ③ of the optical fiber circulator is collimated by the second collimator and reaches the third beam splitter prism, merges with the laser reflected by the fifth reflector at the third beam splitter prism, and reaches the first photodetector and the second photodetector respectively after being split by the third beam splitter prism; after the first photodetector and the second photodetector convert the collected interference light signal into an interference electrical signal, the signal acquisition and processing device performs signal solution and processing on the interference electrical signal, and the obtained angular vibration information is displayed and output by the computer.

[0009] Among them, the spatial optical path device used is an optical lens or an optical fiber device.

[0010] Wherein, the standard vibration exciter is a low-frequency standard exciter, a medium-frequency standard exciter or a high-frequency standard exciter.

[0011] The present invention also provides a three-degree-of-freedom angle measurement method based on radially polarized light, which uses the device of the present invention to implement the measurement, comprising the following steps:

[0012] The laser light source generates fundamental frequency light, which is divided into two laser beams after passing through the first beam splitter prism, wherein the transmitted coherent state laser is incident on the second reflector, and reaches the second beam splitter prism after being reflected by the second reflector; the laser reflected by the first beam splitter prism is incident on the third reflector, and after being reflected by the third reflector, a compressed state laser is generated by a continuous variable light source generation module, and the generated compressed state laser reaches the second beam splitter prism; after passing through the second beam splitter prism, the two laser beams are transmitted and reflected respectively, and both the transmitted light and the reflected light contain coherent state and compressed state lasers; one of the laser beams is frequency shifted by an acousto-optic frequency shifter and reaches the fifth reflector; the other laser beam is incident on the fourth reflector, and reaches the optical fiber circulator after being reflected by the fourth reflector; when the laser signal is input from the first port of the optical fiber circulator, it is output from the second port in numerical order, and the laser signal output from the second port is incident on the target target mirror after passing through the first collimator; the target target mirror is fixed on a standard vibration exciter, and the standard vibration exciter generates a standard mechanical vibration signal under the control of a vibration controller, with reference to The accelerometer and the target mirror are fixedly installed on the standard vibration exciter; the output signal of the reference accelerometer is used as the feedback signal of the vibration control, and the output electrical signal is fed back to the vibration controller, which receives the feedback signal from the reference accelerometer, and performs calculation and solution according to a preset algorithm, thereby realizing the control of the high-frequency standard mechanical vibration signal; after the laser is reflected by the target mirror, the laser light signal carrying the high-frequency angular vibration is incident into the optical fiber through the first collimator and transmitted to the port ② of the optical fiber circulator, and is output from the port ③; the laser signal output from the port ③ of the optical fiber circulator is collimated by the second collimator and reaches the third beam splitter prism, merges with the laser reflected by the fifth reflector at the third beam splitter prism, and reaches the first photodetector and the second photodetector respectively after being split by the third beam splitter prism; after the first photodetector and the second photodetector convert the collected interference light signal into an interference electrical signal, the signal acquisition and processing device performs signal solution and processing on the interference electrical signal to obtain angular vibration information.

[0013] Beneficial effects:

[0014] 1. The present invention utilizes a continuous variable squeezed state quantum light source in combination with linear interferometry, and proposes a high-frequency angular vibration measurement device based on a squeezed state light source to achieve measurement of high-frequency angular vibration parameters. The measurement results are expected to break through the standard quantum limit, effectively improve the measurement accuracy, and solve the problem that the measurement results in the traditional interferometry process cannot break through the standard quantum limit, thereby achieving high-sensitivity measurement.

[0015] 2. The advantages compared with the prior art are: when the prior art performs high-frequency angular vibration measurement, the laser light source used is usually a coherent state laser, while the present invention uses a compressed state light source as the measurement light source, and injects the compressed state light source into the high-frequency angular vibration measurement device, which can break through the shot noise limit of classical measurement in high-frequency angular vibration measurement and achieve higher-precision measurement; most of the prior art uses spatial optical path devices to build optical paths for measurement, while all spatial optical path devices in the device of the present invention can be replaced by optical fiber devices to achieve full optical fiber device measurement, and the measurement stability and reliability are further improved while ensuring that the measurement device is miniaturized.

[0016] 3. The method of the present invention is implemented based on the device of the present invention, and utilizes a continuous variable squeezed state quantum light source in combination with linear interferometry to achieve measurement of high-frequency angular vibration parameters. The measurement result is expected to break through the standard quantum limit, thereby effectively improving the measurement accuracy and solving the problem that the measurement result in the traditional interferometry process cannot break through the standard quantum limit, thereby achieving high-sensitivity measurement. The method of the present invention is implemented based on the device of the present invention, and uses a squeezed state light source as a measurement light source. The squeezed state light source is injected into a high-frequency angular vibration measurement device, which can break through the shot noise limit of classical measurement in high-frequency angular vibration measurement and achieve higher-precision measurement.

[0017] 4. In the device of the present invention, the standard vibration exciter can be replaced with a low-frequency and medium-frequency standard exciter, and the device of the present invention can be expanded to be suitable for low-frequency and medium-frequency angular vibration measurement devices. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of an angular vibration measurement device based on a compressed state light source according to the present invention. DETAILED DESCRIPTION

[0019] The present invention is described in detail below with reference to the accompanying drawings and embodiments.

[0020] As a non-classical light field, squeezed light can improve the phase measurement accuracy by reducing the noise of a certain orthogonal component; at the same time, squeezed light redistributes the fluctuations of two conjugate observable quantities, so that the fluctuation of one of the observable quantities is reduced, thereby improving the measurement sensitivity. The present invention provides a high-frequency angular vibration measurement device based on a squeezed state light source, the structure of which is as follows Figure 1As shown, it comprises: a laser light source (1), a first beam splitter prism (2), a second reflector (3), a third reflector (4), a continuous variable light source generation module (5), a second beam splitter prism (6), an acousto-optic frequency shifter (7), a fourth reflector (8), a fifth reflector (9), an optical fiber circulator (10), a first collimator (11), a second collimator (12), a third beam splitter prism (13), a first photodetector (14), a target mirror (15), a reference accelerometer (16), a standard vibration exciter (17), a second photodetector (18), a signal acquisition and processing device (19), a vibration controller (20) and a computer (21).

[0021] The fundamental frequency light (coherent laser) generated by the laser light source (1) is divided into two laser beams after passing through the first beam splitter prism (2), wherein the transmitted laser beam is incident on the second reflector (3), and reaches the second beam splitter prism (6) after being reflected by the second reflector; the reflected laser beam is incident on the third reflector (4), and enters the continuous variable light source generation module (5) after being reflected by the third reflector to generate compressed laser beam (measurement light source), and the generated compressed laser beam is also sent to the second beam splitter prism (6); the two laser beams are combined and split on the second beam splitter prism (6), and after being transmitted and reflected by the second beam splitter prism (6), the transmitted light and the reflected light both contain coherent laser beams and compressed laser beams; one of the laser beams passes through an acousto-optic frequency shifter (7) After frequency shifting, it reaches the fifth reflector (9); another laser beam is incident on the fourth reflector (8), and after being reflected by the fourth reflector (8), it reaches the optical fiber circulator (10); the optical signal is input from port ① of the optical fiber circulator (10), and is output from port ② in numerical order, and the laser signal output from port ② is incident on the target target mirror (15) after passing through the first collimator (11); the target target mirror (15) is fixed on the standard vibration exciter (17), and the standard vibration exciter (17) generates a high-frequency standard mechanical vibration signal under the control of the vibration controller (20), and the reference accelerometer (16) and the target target mirror (15) are fixedly installed on the standard vibration exciter (17). The output signal of the reference accelerometer (16) is used as a feedback signal for vibration control. After the output electrical signal (charge or voltage) is amplified by a preamplifier, the amplified vibration acceleration signal is fed back to the vibration controller (20). The vibration controller (20) receives the feedback signal from the reference accelerometer (16), and performs calculation and solution according to a preset algorithm, thereby realizing accurate control of the high-frequency standard mechanical vibration signal. After the laser is reflected by the target mirror (15), the laser light signal carrying the high-frequency angular vibration is incident on the optical fiber through the first collimator (11) and transmitted to the port ② of the optical fiber circulator (10), and is output from the port ③. The optical fiber circulator (10) outputs the laser light from the port ③. The output laser signal is collimated by the second collimator (12) and reaches the third beam splitter prism (13), where it merges with the laser reflected by the fifth reflector (9) and respectively reaches the first photodetector (14) and the second photodetector (18) after being split by the third beam splitter prism (13); after the first photodetector (14) and the second photodetector (18) convert the collected interference light signal into an electrical signal, the signal collection and processing device (19) performs signal analysis and processing on the interference electrical signal, and the high-frequency angular vibration information (such as angular acceleration, etc.) obtained by the processing is displayed and output by the computer (20), thereby realizing on-site high-precision vibration calibration.

[0022] In summary, the device of the present invention utilizes the Mach-Zehnder (MZ) interference optical path structure to achieve the measurement of high-frequency angular vibration. Specifically, the same laser light source is used to generate coherent light and compressed light, wherein the continuous variable light source generation module generates compressed light in a traditional manner; the coherent light and the compressed light are respectively injected into the MZ interference optical path from both ends of the beam splitter prism, and the reflected measurement light carrying angular vibration information is returned to the MZ interference optical path by an optical fiber circulator, and the measurement light and the reference light are combined and interfered by the beam splitter prism to perform zero-beat balance detection.

[0023] Furthermore, the standard vibration exciter (17) can be replaced with a low-frequency and medium-frequency standard exciter, and the device of the present invention is also applicable, that is, the device of the present invention can be expanded to be applicable to low-frequency and medium-frequency angular vibration measurement devices.

[0024] Furthermore, the first beam splitter prism (2), the second beam splitter prism (6), and the third beam splitter prism (13) can be replaced with optical fiber couplers, that is, all spatial optical path devices in the device can be replaced by optical fiber devices, thereby realizing full optical fiber device measurement.

[0025] The present invention also provides an angular vibration measurement method based on a squeezed state light source, which is implemented based on the device of the present invention and includes the following steps:

[0026] The laser light source (1) generates fundamental frequency light, which is divided into two laser beams after passing through a first beam splitter prism (2) with a certain splitting ratio, wherein the transmitted coherent state laser is incident on a second reflector (3), and after being reflected by the reflector, reaches the second beam splitter prism (6); the laser reflected by the first beam splitter prism (2) is incident on a third reflector (4), and after being reflected by the third reflector, a compressed state laser is generated by a continuous variable light source generation module (5), and the generated compressed state laser reaches the second beam splitter prism (6); after the two laser beams pass through the second beam splitter prism (6), they are transmitted and reflected respectively according to the splitting ratio, and the transmitted light and the reflected light both contain coherent state and compressed state lasers. One of the laser beams is frequency shifted by an acousto-optic frequency shifter (7) and reaches a fifth reflector (9); the other laser beam is incident on a fourth reflector (8), and after being reflected by the fourth reflector (08), reaches an optical fiber circulator (10). When a laser signal is input from port ① of the optical fiber circulator, it is output from port ② in numerical order with very little loss. The laser signal output from port ② is incident on a target mirror (15) after passing through a first collimator (11). The target mirror (15) is fixed on a standard vibration exciter (17). The standard vibration exciter (17) generates a high-frequency standard mechanical vibration signal under the control of a vibration controller (20). A reference accelerometer (16) and the target mirror (15) are fixedly mounted on the standard vibration exciter (17). The output signal of the reference accelerometer (16) is used as a feedback signal for vibration control. After the output electrical signal (charge or voltage) is amplified by a preamplifier, the amplified vibration acceleration signal is fed back to the vibration controller (20). The vibration controller (20) receives the feedback signal from the reference accelerometer (16), and performs calculation and solution according to a preset algorithm, thereby realizing accurate control of the high-frequency standard mechanical vibration signal. After the laser is reflected by the target mirror (15), the laser light signal carrying the high-frequency angular vibration is incident on the optical fiber through the first collimator (11) and transmitted to the port ② of the optical fiber circulator (10), and is output from the port ③. The optical fiber circulator (10) outputs the laser light from the port ③. The output laser signal is collimated by the second collimator (12) and reaches the third beam splitter prism (13), where it merges with the laser reflected by the fifth reflector (9) and respectively reaches the first photodetector (14) and the second photodetector (18) after being split by the third beam splitter prism (13); the first photodetector (14) and the second photodetector (18) convert the collected interference light signals into electrical signals, and then the signal collection and processing device (19) performs signal analysis and processing on the interference electrical signals, and the high-frequency angular vibration information (such as angular acceleration, etc.) obtained after the processing is displayed and output by the computer (20), thereby realizing high-precision angular vibration measurement.

[0027] In summary, the above are only preferred embodiments of the present invention and are not intended to limit the protection scope of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An angular vibration measurement device based on a compressed state light source, characterized in that: It includes a laser light source, a beam splitter prism, a continuous variable light source generation module, an MZ interference optical path, an optical fiber circulator and a standard vibration exciter; The same laser light source generates coherent light and compressed light, wherein the continuous variable light source generating module generates compressed light; the coherent light and the compressed light are respectively injected into the MZ interference optical path from both ends of the beam splitter prism, and the reflected measurement light carrying angular vibration information is returned to the MZ interference optical path by using an optical fiber circulator, and the measurement light and the reference light are combined and interfered by the beam splitter to perform zero-beat balance detection; the standard vibration exciter is used to generate a standard mechanical vibration signal.

2. The device according to claim 1, characterized in that Specifically includes a laser light source, a first beam splitter prism, a second reflector, a third reflector, a continuous variable light source generation module, a second beam splitter prism, an acousto-optic frequency shifter, a fourth reflector, a fifth reflector, an optical fiber circulator, a first collimator, a second collimator, a third beam splitter prism, a first photodetector, a target mirror, a reference accelerometer, a standard vibration exciter, a second photodetector, a signal acquisition and processing device, a vibration controller and a computer; The coherent light generated by the laser light source is divided into two laser beams after passing through the first beam splitter prism, wherein the transmitted laser beam is incident on the second reflector and reaches the second beam splitter prism after being reflected by the second reflector; the reflected laser beam is incident on the third reflector and enters the continuous variable light source generation module after being reflected by the third reflector to generate compressed light, and the compressed light is also sent to the second beam splitter prism; the two laser beams are combined and split on the second beam splitter prism, and after being transmitted and reflected by the second beam splitter prism, both the transmitted light and the reflected light contain coherent light and compressed light; one of the laser beams is frequency-shifted by the acousto-optic frequency shifter and reaches the fifth reflector; the other laser beam is incident on the fourth reflector and reaches the optical fiber circulator after being reflected by the fourth reflector; the optical signal is input from port ① of the optical fiber circulator and output from port ② in numerical order, and the laser signal output from port ② is incident on the target target mirror after passing through the first collimator; the target target mirror is fixed on a standard vibration exciter, and the standard vibration exciter generates a standard mechanical vibration signal under the control of a vibration controller, and the reference accelerometer and the target target mirror are used as reference accelerometers and target targets. The mirror is fixedly mounted on a standard vibration exciter; the output signal of the reference accelerometer is used as a feedback signal for vibration control, and the output electrical signal is fed back to the vibration controller, which receives the feedback signal from the reference accelerometer and performs calculation and solution according to a preset algorithm, thereby realizing precise control of the standard mechanical vibration signal; after the laser is reflected by the target mirror, the laser light signal carrying the angular vibration is incident into the optical fiber through the first collimator and transmitted to the port ② of the optical fiber circulator, and is output from the port ③; the laser signal output from the port ③ of the optical fiber circulator is collimated by the second collimator and reaches the third beam splitter prism, merges with the laser reflected by the fifth reflector at the third beam splitter prism, and reaches the first photodetector and the second photodetector respectively after being split by the third beam splitter prism; after the first photodetector and the second photodetector convert the collected interference light signal into an interference electrical signal, the signal acquisition and processing device performs signal solution and processing on the interference electrical signal, and the obtained angular vibration information is displayed and output by the computer.

3. The device according to claim 1 or 2, characterized in that ,The spatial optical path devices used are optical lenses or optical fiber devices.

4. The device according to claim 1 or 2, characterized in that ,The standard vibration exciter is a low-frequency standard exciter, a medium-frequency standard exciter or a high-frequency standard exciter.

5. A three-degree-of-freedom angle measurement method based on radially polarized light, characterized in that: The measurement is performed using the device as claimed in claim 2, comprising the following steps: The laser light source generates fundamental frequency light, which is divided into two laser beams after passing through the first beam splitter prism, wherein the transmitted coherent state laser is incident on the second reflector, and reaches the second beam splitter prism after being reflected by the second reflector; the laser reflected by the first beam splitter prism is incident on the third reflector, and after being reflected by the third reflector, a compressed state laser is generated by a continuous variable light source generation module, and the generated compressed state laser reaches the second beam splitter prism; after passing through the second beam splitter prism, the two laser beams are transmitted and reflected respectively, and both the transmitted light and the reflected light contain coherent state and compressed state lasers; one of the laser beams is frequency shifted by an acousto-optic frequency shifter and reaches the fifth reflector; the other laser beam is incident on the fourth reflector, and reaches the optical fiber circulator after being reflected by the fourth reflector; when the laser signal is input from the first port of the optical fiber circulator, it is output from the second port in numerical order, and the laser signal output from the second port is incident on the target target mirror after passing through the first collimator; the target target mirror is fixed on a standard vibration exciter, and the standard vibration exciter generates a standard mechanical vibration signal under the control of a vibration controller, with reference to The accelerometer and the target mirror are fixedly installed on the standard vibration exciter; the output signal of the reference accelerometer is used as the feedback signal of the vibration control, and the output electrical signal is fed back to the vibration controller, which receives the feedback signal from the reference accelerometer, and performs calculation and solution according to a preset algorithm, thereby realizing the control of the high-frequency standard mechanical vibration signal; after the laser is reflected by the target mirror, the laser light signal carrying the high-frequency angular vibration is incident into the optical fiber through the first collimator and transmitted to the port ② of the optical fiber circulator, and is output from the port ③; the laser signal output from the port ③ of the optical fiber circulator is collimated by the second collimator and reaches the third beam splitter prism, merges with the laser reflected by the fifth reflector at the third beam splitter prism, and reaches the first photodetector and the second photodetector respectively after being split by the third beam splitter prism; after the first photodetector and the second photodetector convert the collected interference light signal into an interference electrical signal, the signal acquisition and processing device performs signal solution and processing on the interference electrical signal to obtain angular vibration information.

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