An interferometric spectral analysis device and analysis method

Abstract

This invention provides an interferometric spectral analysis device and method. The analysis device includes: a reference light source that generates a reference optical signal; a coupler that couples the input optical signal and the reference optical signal into a combined optical signal; a reflecting cavity that receives the combined optical signal, moves a reflecting mirror, and outputs a combined optical interference signal; a circulator that outputs the combined optical interference signal to a first optical filter and a second optical filter; the first optical filter that filters out the reference optical interference signal to obtain the input optical interference signal; the second optical filter that filters out the input optical interference signal to obtain the reference optical interference signal; a first optical signal detection unit that detects the total power of the input optical signal; a second optical signal detection unit that detects the power of the input optical interference signal; a third optical signal detection unit that detects the power of the reference optical interference signal; and a CPU that controls the movement of the reflecting mirror in the reflecting cavity to obtain the total power of the input optical signal, the power of the input optical interference signal, and the power of the reference optical interference signal.

Description

Technical Field

[0001] This invention relates to the field of spectroscopy, and in particular to an interferometric spectral analysis device and analysis method. Background Technology

[0002] Existing spectroscopic analysis devices typically have the following structure:

[0003] 1: Dispersive spectral analysis device, the principle of which is to use a grating to disperse light of different wavelengths, and then perform spectral analysis on the dispersed light through a detector array.

[0004] The spectral resolution of a grating-type spectral analyzer is determined by the grating. The higher the required spectral resolution, the more exponentially the cost of manufacturing the grating increases. The accuracy and cost of the grating limit the performance of the grating-type spectral analyzer.

[0005] 2: Interferometric spectral analysis device. Its principle is to use the interference effect of light to obtain spectral analysis results by analyzing the interference image generated by the optical reflection cavity during the change process.

[0006] The resolution of an interferometric spectral analyzer is determined solely by the length of the reflecting cavity. The longer the cavity, the higher the spectral resolution. However, interferometric spectral analyzers require a cavity control system capable of precisely controlling changes in the cavity. Typically, optical communication operates in the wavelength range of 1300nm-1600nm, which is on the nm level. Therefore, controlling the reflecting cavity to the nm level is necessary to achieve nm-level spectral resolution. The high cost of large-stroke and high-precision cavity control systems significantly hinders the development of interferometric spectrometers.

[0007] Therefore, it is necessary to provide an interferometric spectral analysis device and analysis method to effectively solve the problems existing in the current interferometric spectral analysis devices. Summary of the Invention

[0008] This invention provides an interferometric spectral analysis device and method. By introducing a reference light source and comparing and analyzing a known reference light signal and an input light signal in the same optical path, the spectral composition of the input light signal can be calculated, thus reducing the dependence of the interferometric spectral analysis device on a large-stroke and high-precision cavity control system.

[0009] This invention provides an interferometric spectral analysis device, comprising:

[0010] A reference light source is used to generate a reference light signal;

[0011] A coupler is used to couple the input optical signal to be analyzed with a reference optical signal into a combined optical signal;

[0012] A reflecting cavity includes a cavity body and a vertically disposed movable reflector within the cavity body. The reflecting cavity is located behind the coupler to receive a combined optical signal and to make the combined optical signal shine perpendicularly onto the reflector. By moving the reflector, the combined optical signal input to the reflecting cavity interferes with the reflected optical signal reflected by the reflector, and a combined optical interference signal is output.

[0013] A circulator is disposed between the coupler and the reflecting cavity to isolate the combined optical signal and the combined optical interference signal returning via the reflecting cavity, and to output the combined optical interference signal to the first optical filter and the second optical filter;

[0014] The first optical filter is used to filter out the reference optical interference signal in the combined optical interference signal to obtain the input optical interference signal;

[0015] The second optical filter is used to filter out the input optical interference signal in the combined optical interference signal to obtain the reference optical interference signal;

[0016] The first optical signal detection unit collects the input optical signal to detect the total power of the input optical signal;

[0017] The second optical signal detection unit is connected to the first optical filter and is used to detect the power of the input optical interference signal;

[0018] The third optical signal detection unit is connected to the second optical filter and is used to detect the power of the reference optical interference signal;

[0019] The CPU is used to control the movement of the mirror in the reflecting cavity, obtain the total power of the input optical signal, the power of the input optical interference signal and the power of the reference optical interference signal, and calculate the wavelength of the input optical signal and the power corresponding to the wavelength by combining the known reference wavelength of the reference optical signal.

[0020] Preferably, an isolator is provided on the front side of the coupler, and the input optical signal enters the coupler through the isolator.

[0021] Preferably, a collimator is provided at the entrance of the reflecting cavity. The collimator is used to transmit the combined optical signal into the reflecting cavity. The end face of the collimator connected to the optical path interface of the reflecting cavity is the interference point between the combined optical signal and the reflected optical signal of the combined optical signal.

[0022] Preferably, the first optical signal detection unit includes a first photodiode and a first analog-to-digital converter connected in sequence. The first analog-to-digital converter is connected to the CPU. The first photodiode collects the input optical signal, obtains the total power of the input optical signal, and converts it into a digital signal by the first analog-to-digital converter and sends it to the CPU.

[0023] Preferably, the second optical signal detection unit includes a second photodiode and a second analog-to-digital converter connected in sequence. The second analog-to-digital converter is connected to the CPU. The second photodiode collects the input optical interference signal, obtains the power of the input optical interference signal, and converts it into a digital signal by the second analog-to-digital converter and sends it to the CPU.

[0024] Preferably, the third optical signal detection unit includes a third photodiode and a third analog-to-digital converter connected in sequence. The third analog-to-digital converter is connected to the CPU. The third photodiode collects a reference optical interference signal, obtains the power of the reference optical interference signal, and converts it into a digital signal by the third analog-to-digital converter and sends it to the CPU.

[0025] Based on the same concept, the present invention also provides an analysis method for the above-mentioned interferometric spectral analysis device, comprising the following steps:

[0026] The CPU obtains the total power of the input optical signal through the first optical signal detection unit;

[0027] The reference light source is turned on, and the CPU controls the mirror in the reflecting cavity to move at a set speed.

[0028] While the reflector moves, the CPU obtains the power of the reference light interference signal through the third light signal detection unit; the CPU obtains the power of the input light interference signal through the second light signal detection unit.

[0029] After performing a Fourier transform on the power of the reference light interference signal, the center point is determined to obtain the interference frequency of the reference light signal.

[0030] Performing a Fourier transform on the power of the input optical interference signal yields the proportional relationship between the interference frequency and the amplitude at each frequency point of the input optical signal; the proportional relationship between the amplitudes at each frequency point of the input optical signal is the proportional relationship between the power at each frequency point of the input optical signal.

[0031] Based on the relationship between the wavelength and interference frequency of the input optical signal and the wavelength and interference frequency of the reference optical signal, the wavelength of the input optical signal corresponding to each frequency point is calculated.

[0032] The power of each frequency point of the input optical signal can be calculated based on the fact that the total power of the input optical signal is equal to the sum of the powers of each frequency point of the input optical signal.

[0033] Preferably, the wavelength and interference frequency of the input optical signal satisfy the following formula with the wavelength and interference frequency of the reference optical signal:

[0034]

[0035] in, The wavelength of the input optical signal; The interference frequency of the input optical signal; The wavelength of the reference optical signal; The interference frequency of the reference optical signal.

[0036] Preferably, the wavelength of the input optical signal corresponding to each frequency point is calculated using the following formula:

[0037]

[0038] Where n = 0, 1, 2, ..., (1 / 2)f s f s Sampling frequency, The wavelength of the nth frequency point of the input optical signal; The frequency of the nth frequency point of the input optical signal; The wavelength of the reference optical signal; The interference frequency of the reference optical signal.

[0039] Preferably, the power of the input optical signal at each frequency point is calculated using the following formulas:

[0040]

[0041] Where n = 0, 1, 2, ..., (1 / 2)f s f s Sampling frequency, The total power of the input optical signal; The power of the nth frequency point of the input optical signal; FFT_0:FFT_1:...:FFT_n represents the proportional relationship of the amplitudes of each frequency point obtained by performing a Fourier transform on the power signal of the input optical interference signal.

[0042] Compared with the prior art, the technical solution of the embodiments of the present invention has the following beneficial effects:

[0043] This invention provides an interferometric spectral analysis device and method. It introduces a reference light source and uses digital signal processing to compare and analyze the interference signals of a known reference light signal and the input light signal to be analyzed in the same optical path. The spectral components of the input light signal are calculated from the known reference light signal. This transforms the requirement for controlling the cavity length with nm-level precision into a requirement for the wavelength stability of the reference light source. While reducing the precision requirements for controlling the reflection cavity in the interferometric spectral analysis device, it improves the spectral analysis precision to the same 0.01 nm level as the reference light source, thus improving the performance of the interferometric spectrometer while reducing system costs. Attached Figure Description

[0044] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention, but not all embodiments. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0045] Figure 1 A schematic diagram of an interferometric spectral analysis device provided in one embodiment of the present invention;

[0046] Figure 2 A flowchart of an analysis method using an interferometric spectral analysis device provided in an embodiment of the present invention.

[0047] In the picture:

[0048] 1-Reference light source; 2-Isolator; 3-Coupled; 4-Reflecting cavity; 41-Cavity; 42-Reflector

[0049] Mirror; 43-collimator; 5-circulator; 6-first optical filter; 7-second optical filter;

[0050] 8-First optical signal detection unit; 81-First photodiode; 82-First analog-to-digital converter;

[0051] 9-Second optical signal detection unit; 91-Second photodiode; 92-Second analog-to-digital converter;

[0052] 10-Third optical signal detection unit; 101-Third photodiode; 102-Third analog-to-digital converter;

[0053] 11-CPU. Detailed Implementation

[0054] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0055] The technical solution of the present invention will be described in detail below with reference to specific embodiments. These specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments.

[0056] To address the problems existing in the prior art, this invention provides an interferometric spectral analysis device and method. By introducing a reference light source and comparing and analyzing a known reference light signal and an input light signal in the same optical path, the spectral composition of the input light signal is calculated, thereby reducing the dependence of the interferometric spectral analysis device on a large-stroke and high-precision cavity control system.

[0057] Figure 1 A schematic diagram of an interferometric spectral analysis device provided in one embodiment of the present invention; Figure 2 A flowchart of an analysis method using an interferometric spectral analysis device provided in an embodiment of the present invention.

[0058] Now see Figure 1 This invention provides an interferometric spectral analysis device, comprising:

[0059] Reference light source 1 is used to generate a reference light signal;

[0060] Coupler 3 is used to couple the input optical signal to be analyzed with the reference optical signal into a combined optical signal;

[0061] The reflecting cavity 4 includes a cavity 41 and a movable reflecting mirror 42 vertically disposed in the cavity 41. The reflecting cavity 4 is disposed on the rear side of the coupler 3 to receive the combined optical signal and to make the combined optical signal vertically illuminate the reflecting mirror 42. When the reflecting mirror 42 is moved, the combined optical signal input to the reflecting cavity 4 interferes with the reflected optical signal reflected by the reflecting mirror 42, and outputs a combined optical interference signal.

[0062] Circulator 5 is disposed between coupler 3 and reflective cavity 4 to isolate the combined optical signal and the combined optical interference signal returned via reflective cavity 4, and outputs the combined optical interference signal to the first optical filter 6 and the second optical filter 7.

[0063] The first optical filter 6 is used to filter out the reference optical interference signal in the combined optical interference signal to obtain the input optical interference signal;

[0064] The second optical filter 7 is used to filter out the input optical interference signal in the combined optical interference signal to obtain the reference optical interference signal;

[0065] The first optical signal detection unit 8 collects the input optical signal to detect the total power of the input optical signal;

[0066] The second optical signal detection unit 9 is connected to the first optical filter 6 and is used to detect the power of the input optical interference signal;

[0067] The third optical signal detection unit 10 is connected to the second optical filter 7 and is used to detect the power of the reference optical interference signal;

[0068] The CPU (Central Processing Unit) 11 is used to control the movement of the reflector 42 in the reflector cavity 4, obtain the total power of the input optical signal, the power of the input optical interference signal and the power of the reference optical interference signal, and calculate the wavelength of the input optical signal and the power corresponding to the wavelength by combining the known reference wavelength of the reference optical signal.

[0069] Specifically, reference light source 1 employs a high-precision laser source, which emits wavelength-stable laser light, serving as the reference light. Due to advancements in laser technology, a low-cost two-stage temperature control loop can control the temperature variation of a typical DFB (Distributed Feedback Laser) laser to within 0.03℃, thus stabilizing the wavelength of the emitted laser within 0.001nm.

[0070] In some embodiments, an isolator 2 is provided on the front side of the coupler 3, and the input optical signal enters the coupler 3 through the isolator 2; to prevent the reference optical signal of the reference light source 1 from interfering with the input optical path and causing interference to the first optical signal detection unit 8.

[0071] Specifically, the circulator 5 isolates the combined optical signal and the combined optical interference signal returned via the reflector cavity 4, preventing the returned optical signal from interfering with the reference light source 1 and causing the reference light source 1 to become unstable.

[0072] Specifically, the wavelength range of the input light is usually 1300nm-1600nm, while the wavelength range of the laser used as the reference light is usually 200nm-600nm. The wavelength difference between the two is significant, and the first optical filter 6 and the second optical filter 7 achieve optical filtering based on the wavelength range.

[0073] In some embodiments, a collimator 43 is provided at the entrance of the reflecting cavity 4. The collimator 43 is used to transmit the combined optical signal to the reflecting cavity 4. The end face of the collimator 43 connected to the optical path interface of the reflecting cavity 4 is the interference point between the combined optical signal and the reflected optical signal of the combined optical signal.

[0074] In some embodiments, the first optical signal detection unit 8 includes a first photodiode 81 and a first analog-to-digital converter 82 connected in sequence. The first analog-to-digital converter 82 is connected to the CPU 11. The first photodiode 81 collects the input optical signal, obtains the total power of the input optical signal, and converts it into a digital signal by the first analog-to-digital converter 82 and sends it to the CPU 11.

[0075] In some embodiments, the second optical signal detection unit 9 includes a second photodiode 91 and a second analog-to-digital converter 92 connected in sequence. The second analog-to-digital converter 92 is connected to the CPU 11. The second photodiode 91 collects the input optical interference signal, obtains the power of the input optical interference signal, and converts it into a digital signal by the second analog-to-digital converter 92 and sends it to the CPU 11.

[0076] In some embodiments, the third optical signal detection unit 10 includes a third photodiode 101 and a third analog-to-digital converter 102 connected in sequence. The third analog-to-digital converter 102 is connected to the CPU 11. The third photodiode 101 collects the reference light interference signal, obtains the power of the reference light interference signal, and converts it into a digital signal by the third analog-to-digital converter 102 and sends it to the CPU 11.

[0077] See Figure 2 The present invention also provides an analysis method for an interferometric spectral analysis device, comprising the following steps:

[0078] S1: CPU 11 obtains the total power of the input optical signal through the first optical signal detection unit 8;

[0079] S2: Turn on the reference light source 1, and the CPU 11 controls the reflector 42 in the reflective cavity 4 to move at the set speed;

[0080] S3: While the reflector 42 moves, the CPU 11 obtains the power of the reference light interference signal through the third light signal detection unit 10; the CPU 11 obtains the power of the input light interference signal through the second light signal detection unit 9;

[0081] S4: After performing a Fourier transform on the power of the reference light interference signal, the center point is solved to obtain the interference frequency of the reference light signal;

[0082] S5: Perform a Fourier transform on the power of the input optical interference signal to obtain the proportional relationship between the interference frequency and the amplitude of each frequency point of the input optical signal; the proportional relationship of the amplitude of each frequency point of the input optical signal is the proportional relationship of the power of each frequency point of the input optical signal.

[0083] S6: Based on the relationship between the wavelength and interference frequency of the input optical signal and the wavelength and interference frequency of the reference optical signal, the wavelength of the input optical signal corresponding to each frequency point is calculated;

[0084] S7: The power of each frequency point of the input optical signal is calculated based on the fact that the total power of the input optical signal is equal to the sum of the powers of each frequency point of the input optical signal.

[0085] Specifically, in step S2, the CPU 11 controls the mirror 42 in the reflecting cavity 4 to move at a rate of Lnm / s; during the process of the reference light changing the length of the cavity 41 by Lnm, the number of times the reference light and its reflected light interfere with each other, superimposed or canceled is... , Let λ be the wavelength of the reference light, then the interference frequency of the reference light is expressed as:

[0086]

[0087] Assuming the wavelength of the input optical signal is Then, during the process of the input light changing length Lnm in cavity 41, the number of times the input light and its reflected light interfere with each other, superimposed or canceled is: The interference frequency of the input light is then expressed as:

[0088]

[0089] The wavelength and interference frequency of the input optical signal satisfy the following formula with the wavelength and interference frequency of the reference optical signal:

[0090]

[0091] in, The wavelength of the input optical signal; The interference frequency of the input optical signal; The wavelength of the reference optical signal; The interference frequency of the reference optical signal.

[0092] Following the same logic for single-wavelength signals, when the input optical signal is a broadband signal, Fourier transform analysis of the interference signal of the input light yields the wavelength of the input optical signal at each frequency point, calculated using the following formula:

[0093]

[0094] Where n = 0, 1, 2, ..., (1 / 2)f s f s Sampling frequency, The wavelength of the nth frequency point of the input optical signal; The frequency of the nth frequency point of the input optical signal; The wavelength of the reference optical signal; The interference frequency of the reference optical signal.

[0095] In some embodiments, the power of the input optical signal at each frequency point is calculated using the following formulas:

[0096]

[0097] Where n = 0, 1, 2, ..., (1 / 2)f s f s Sampling frequency, The total power of the input optical signal; The power of the nth frequency point of the input optical signal; FFT_0:FFT_1:...:FFT_n represents the proportional relationship of the amplitudes of each frequency point obtained by performing a Fourier transform on the power signal of the input optical interference signal.

[0098] Compared to existing technologies, by performing Fourier transform analysis on the interference signal of the input light, the frequencies of the input light signal corresponding to each frequency point are obtained, and then based on... By calculating the wavelength of the input optical signal corresponding to each frequency point, this invention transforms the control requirement of the cavity 41 with nm-level precision into the wavelength stability requirement of the reference light source 1, thereby reducing the control precision requirements of the reflection cavity in the interferometric spectral analysis device.

[0099] In summary, the interferometric spectral analysis device and method provided by this invention introduces a reference light source 1 and uses digital signal processing to compare and analyze the interference signals of a known reference light signal and the input light signal to be analyzed in the same optical path. The spectral composition of the input light signal is calculated from the known reference light signal. The control requirements for the length of the cavity 41 with nm-level precision are transformed into wavelength stability requirements for the reference light source 1. This reduces the control precision requirements of the interferometric spectral analysis device on the reflection cavity while improving the spectral analysis precision to the same 0.01 nm level as the reference light source 1. This improves the performance of the interferometric spectrometer while reducing system costs.

[0100] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention 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 or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. An interferometric spectral analysis device, characterized in that, include: A reference light source is used to generate a reference light signal; A coupler is used to couple the input optical signal to be analyzed with a reference optical signal into a combined optical signal; A reflecting cavity includes a cavity body and a movable reflecting mirror vertically disposed within the cavity body. The reflecting cavity is located behind the coupler to receive a combined optical signal and to make the combined optical signal illuminate the reflecting mirror perpendicularly. By moving the reflecting mirror, the combined optical signal input to the reflecting cavity interferes with the reflected optical signal reflected by the reflecting mirror, and a combined optical interference signal is output. A circulator is disposed between the coupler and the reflecting cavity to isolate the combined optical signal and the combined optical interference signal returning via the reflecting cavity, and to output the combined optical interference signal to the first optical filter and the second optical filter; The first optical filter is used to filter out the reference optical interference signal in the combined optical interference signal to obtain the input optical interference signal; the second optical filter is used to filter out the input optical interference signal in the combined optical interference signal to obtain the reference optical interference signal. The first optical signal detection unit collects the input optical signal to detect the total power of the input optical signal; The second optical signal detection unit is connected to the first optical filter and is used to detect the power of the input optical interference signal; The third optical signal detection unit is connected to the second optical filter and is used to detect the power of the reference optical interference signal; The CPU is used to control the movement of the mirror in the reflecting cavity, obtain the total power of the input optical signal, the power of the input optical interference signal and the power of the reference optical interference signal, and calculate the wavelength of the input optical signal and the power corresponding to the wavelength by combining the known reference wavelength of the reference optical signal. The CPU obtains the total power of the input optical signal through the first optical signal detection unit; The reference light source is turned on, and the CPU controls the mirror in the reflecting cavity to move at a set speed. While the reflector moves, the CPU obtains the power of the reference light interference signal through the third light signal detection unit; the CPU obtains the power of the input light interference signal through the second light signal detection unit. After performing a Fourier transform on the power of the reference light interference signal, the center point is determined to obtain the interference frequency of the reference light signal. Performing a Fourier transform on the power of the input optical interference signal yields the proportional relationship between the interference frequency and the amplitude at each frequency point of the input optical signal; the proportional relationship between the amplitudes at each frequency point of the input optical signal is the proportional relationship between the power at each frequency point of the input optical signal. Based on the relationship between the wavelength and interference frequency of the input optical signal and the wavelength and interference frequency of the reference optical signal, the wavelength of the input optical signal corresponding to each frequency point is calculated. The power of each frequency point of the input optical signal can be calculated based on the fact that the total power of the input optical signal is equal to the sum of the powers of each frequency point of the input optical signal. The wavelength and interference frequency of the input optical signal satisfy the following formula with the wavelength and interference frequency of the reference optical signal: in, The wavelength of the input optical signal; The interference frequency of the input optical signal; The wavelength of the reference optical signal; The interference frequency of the reference optical signal; The wavelength of the input optical signal at each frequency point is calculated using the following formula: Where n = 0, 1, 2, ..., (1 / 2)f s f s Sampling frequency, The wavelength of the nth frequency point of the input optical signal; The frequency of the nth frequency point of the input optical signal; The wavelength of the reference optical signal; The interference frequency of the reference optical signal; The power of the input optical signal at each frequency point is calculated using the following formulas: Where n = 0, 1, 2, ..., (1 / 2)f s f s Sampling frequency, The total power of the input optical signal; The power of the nth frequency point of the input optical signal; FFT_0:FFT_1:...:FFT_n represents the proportional relationship of the amplitudes of each frequency point obtained by performing a Fourier transform on the power signal of the input optical interference signal.

2. The interferometric spectral analysis device according to claim 1, characterized in that, An isolator is provided on the front side of the coupler, and the input optical signal enters the coupler through the isolator.

3. The interferometric spectral analysis device according to claim 1, characterized in that, A collimator is provided at the entrance of the reflecting cavity. The collimator is used to transmit the combined optical signal into the reflecting cavity. The end face of the collimator connected to the optical path interface of the reflecting cavity is the interference point between the combined optical signal and the reflected optical signal of the combined optical signal.

4. The interferometric spectral analysis device according to claim 1, characterized in that, The first optical signal detection unit includes a first photodiode and a first analog-to-digital converter connected in sequence. The first analog-to-digital converter is connected to the CPU. The first photodiode collects the input optical signal, obtains the total power of the input optical signal, and converts it into a digital signal by the first analog-to-digital converter and sends it to the CPU.

5. The interferometric spectral analysis device according to claim 1, characterized in that, The second optical signal detection unit includes a second photodiode and a second analog-to-digital converter connected in sequence. The second analog-to-digital converter is connected to the CPU. The second photodiode collects the input optical interference signal, obtains the power of the input optical interference signal, and converts it into a digital signal by the second analog-to-digital converter and sends it to the CPU.

6. The interferometric spectral analysis device according to claim 1, characterized in that, The third optical signal detection unit includes a third photodiode and a third analog-to-digital converter connected in sequence. The third analog-to-digital converter is connected to the CPU. The third photodiode collects the reference light interference signal, obtains the power of the reference light interference signal, and converts it into a digital signal by the third analog-to-digital converter and sends it to the CPU.

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