Calibration device with spectrum self-calibration function and high-resolution spectrum calibration method thereof

Abstract

The invention discloses a calibration device with a spectrum self-calibration function and a high-resolution spectrum calibration method thereof. The device comprises a narrow-band light source, a broadband light source, an optical fiber isolator, a coupler, an interference system, a multi-way switch, an FP (Fabry-Perot) cavity, a collimator, an orthogonal dispersion system and a computer, wherein the orthogonal dispersion system consists of a cylindrical lens, a reflector, a virtual phase array, a grating, a focusing lens and an industrial camera; according to the device, different light source paths are gated, FP cavity modulation and orthogonal dispersion system light splitting are utilized, and an industrial camera is combined to receive light signals. According to the method, the mapping relation between pixels and wavelengths can be established, the two-dimensional spectrum is compressed into the one-dimensional calibration spectrum through light intensity modulation and normalization processing, the calibration process of the orthogonal dispersion system is simplified, and the measurement precision is improved; and system drift can be compensated in real time through self-checking calibration, and the reliability of a measurement result is ensured, so that accurate calibration and measurement of a high-resolution spectrum can be realized.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of precision measurement, in particular to a calibration device with spectral self-calibration function and a high-resolution spectral calibration method. BACKGROUND

[0002] In the manufacturing of large and complex parts such as aero-engine main shafts and ship structural parts, high-precision measurement of geometric features such as deep holes and groove positions is the key to ensuring product performance and safety. Optical coherence tomography (OCT) is widely used in precision measurement due to its non-contact, non-invasive and high-resolution (axial resolution up to microns) advantages. As a key foundation for accurately determining the correspondence between spectral information and depth position, the optimization of spectral calibration based on OCT is crucial to improving measurement accuracy and reliability. In the prior art, there are many deficiencies in spectral calibration based on OCT systems: the calibration method based on absorption spectrum, although it uses the absorption characteristics of gas to improve the stability of light frequency reference, there are dispersion mismatch errors and fiber dispersion compensation problems, and the calibration accuracy is limited; the improved Doppler shift calibration method, although it improves the accuracy by moving the optical module, it requires accurate control of uniform motion and has a large amount of calculation; the spectral domain OCT system based on virtual phase array-grating combination developed by Zhejiang University, although it realizes high spectral resolution and large measurement range, the calibration process is complex and the cost is high. In addition, the existing high-resolution spectral calibration system has high requirements for the spatial position and alignment accuracy of optical elements, and environmental temperature fluctuations, mechanical vibrations and system thermal effects can easily cause the parameters such as reference wavelength position and free spectral range to drift. In the high-resolution scenario, this drift can significantly affect the long-term stability and repeatability of the calibration results, becoming a key bottleneck restricting the application of the technology. SUMMARY

[0003] The present application is to solve the above-mentioned deficiencies in the prior art, and proposes a high-resolution spectral measurement and calibration method with spectral self-calibration function, in order to establish an accurate mapping relationship between pixels and wavelengths, combine light intensity modulation and normalization processing, realize efficient reconstruction of two-dimensional spectral data to one-dimensional calibration spectrum, simplify the calibration process of orthogonal dispersion systems and significantly improve the measurement accuracy. At the same time, through the self-checking and calibration mechanism, the reference wavelength drift and free spectral range offset are compensated in real time, ensuring the long-term reliability and repeatability of high-resolution spectral calibration results in complex environments, thereby providing more efficient and stable spectral calibration technology support for precision measurement of large and complex parts.

[0004] To achieve the above-mentioned application purposes, the technical scheme adopted by the present application is as follows: The application discloses a calibration device with a spectrum self-calibration function, and relates to the technical field of optical spectrum analysis. The narrow-band light source is connected with the A port of the first multi-way switch through an optical fiber, and the broadband light source is connected with the B port of the second multi-way switch through an optical fiber in sequence and in series with an optical fiber isolator, the upper end outlet of a one-to-two coupler and the first multi-way switch. The C port of the first multi-way switch is connected with the A port of the second multi-way switch through an optical fiber in sequence and in series with the first collimator, the FP cavity and the second collimator. The lower end outlet of the one-to-two coupler is connected with the lower end inlet of the two-to-two coupler through an optical fiber, and the upper end inlet of the two-to-two coupler is connected with the B port of the second multi-way switch through an optical fiber. The lower end outlet of the two-to-two coupler is connected with the interference system through an optical fiber. The C port of the second multi-way switch is connected with the orthogonal dispersion system through an optical fiber in sequence and in series with the third collimator. When the narrow-band light source channel is selected, the A port of the first multi-way switch and the A port of the second multi-way switch are selected, so that the narrow-band light emitted by the narrow-band light source is collimated by the first collimator after passing through the first multi-way switch, is incident on the FP cavity, is modulated by the FP cavity, is collimated by the second collimator again, and the twice collimated narrow-band light is emitted to the third collimator through the second multi-way switch and is collimated again, the thrice collimated narrow-band light is incident on the cylindrical lens for beam shaping, the shaped narrow-band light is reflected by the first mirror and the second mirror in sequence, is split in the vertical direction in the virtual phase array, is split in the horizontal direction in the grating, and is finally converged in the focusing lens, the narrow-band two-dimensional dispersed light is received by the industrial camera, and a column of bright spots is generated. When the broadband light source path is activated, the B port of the first multiplexer and the A port of the second multiplexer are activated, so that the broadband light emitted by the broadband light source passes through the fiber optic isolator and the 1-to-2 coupler in sequence. The broadband light emitted from the upper outlet of the 1-to-2 coupler passes through the first multiplexer and is collimated in the first collimator before entering the FP cavity. The narrowband light after being collimated by the FP cavity is modulated and then collimated again by the second collimator. The broadband light after secondary collimation passes through the second multiplexer and is emitted to the third collimator for collimation. The broadband light after tertiary collimation enters the cylindrical lens for beam shaping. The shaped broadband light then passes through the first mirror and the second mirror in sequence for reflection and enters the virtual phase array for vertical beam splitting. It then enters the grating for horizontal beam splitting and finally enters the focusing lens for convergence. The resulting broadband two-dimensional dispersion light is received by the industrial camera and generates a CCD image containing multiple bright stripes. When the interferometric system path is selected, port A of the first multiplexer and port B of the second multiplexer are selected, so that the broadband light emitted by the broadband light source passes through the fiber isolator and the lower outlet of the 1-to-2 coupler in sequence and then enters the 2-to-2 fiber coupler for beam splitting, resulting in two beams that enter the reference arm and sample arm of the interferometric system, respectively. The light returning from the reference arm and sample arm of the interferometric system converges and interferes in the 2-to-2 fiber coupler. The resulting interference signal enters the collimator through the second optical multiplexer for collimation. The collimated interference light then enters the cylindrical lens for beam shaping. The shaped broadband light is reflected by the first and second mirrors in sequence, enters the virtual phase array for vertical beam splitting, then enters the grating for horizontal beam splitting, and finally enters the focusing lens for convergence. The resulting two-dimensional dispersive interference light is received by the industrial camera and produces an interference fringe pattern.

[0005] The high-resolution spectral calibration method with spectral self-calibration function of the present invention is characterized in that it is applied to the calibration device described above and is performed according to the following steps: Step 1: Use the aforementioned column of bright spots as the reference column. and from Find the pixel coordinates of the brightest point corresponding to the wavelength of narrowband light. and its light intensity ; Step 2: In the baseline column The brightest point in the CCD image is identified, along with the center points of the bright stripes corresponding to the brightest points and their adjacent center points. The y-coordinate of the center point of the first bright stripe is recorded. and its light intensity and the y-axis coordinate of the center point of the adjacent second bright fringe. and its light intensity Thus, the row containing the center point of the first bright fringe and the row containing the center point of the second bright fringe are respectively taken as the upper boundary and the lower boundary, and the area between the upper boundary and the lower boundary is taken as the boundary area. The intensity gradient attenuation coefficient k of the virtual phase array in the dispersion direction is calculated using equation (1): (1) Step 3: Use the boundary region to truncate the interference fringe pattern, and then rotate the truncated interference fringe pattern clockwise to compensate for the dispersion shift, thus obtaining the compensated interference fringe pattern. The compensated interference fringe pattern is sparsely sampled along the x-axis according to the grating period, generating a dimension of... The compressed data matrix; where m represents the number of rows in the boundary region, i.e., the number of effective pixels in one FSR period; n represents the number of columns after sparse sampling; Step 4: Process the compressed data matrix using two-dimensional spectral interferometry modulation to obtain a high-density one-dimensional spectral sequence; Step 4.1: Define the current column index as... The current row number is Let the pivot column be the i-th column, and initialize i=1; Step 4.2: Initialization =1, initialize the first upper boundaries of behavior; Step 4.3: Calculate the first element in the compressed data matrix using equation (2). Liede row of pixels P ij Normalized light intensity : (2) In equation (2), For pixel P ij The measured light intensity For pixel P ij The y-axis coordinate; Step 4.4: [The text appears to be incomplete and contains several grammatical errors. A more accurate translation would require the full context.] Assign to Then, return to step 4.3 and execute sequentially until... up to n, thus obtaining the nth The normalized light intensity of all pixels in the column; Step 4.5: [The sentence is incomplete and requires more context to be translated accurately.] Assign to Then, return to step 4.2 and execute sequentially until... Up to m, the normalized light intensity of all pixels in all columns is obtained and stitched together to form a complete high-density one-dimensional spectral sequence; Step 5: Calculate the wavelength value of any k-th data point in the high-density one-dimensional spectral sequence using equation (3). : (3) In equation (3), The reference wavelength corresponding to the broadband light source. This is expressed as a step of wavelength, and we have: (4) In equation (4), N is the number of effective pixels in one FSR cycle within the boundary region; Step Six: Using the wavelength value corresponding to each data point in the high-density one-dimensional spectral sequence as the x-axis, ... Using the vertical axis as the ordinate, the spectrum of the broadband light source is thus calibrated.

[0006] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. This invention employs a dual-light source design, utilizing both a narrowband and a broadband light source, combined with an optical switch for rapid path switching. This effectively solves the problems of limited wavelength coverage and susceptibility to environmental interference during calibration when using a single light source. The narrowband light source is used for precise positioning of the reference wavelength, while the broadband light source is used for calibrating the free spectral range (FSR). This not only expands the calibration range but also significantly improves the accuracy of wavelength positioning and the system's adaptability, making it particularly suitable for applications requiring extremely high wavelength stability in high-resolution measurements.

[0007] 2. This invention establishes a light intensity attenuation model with respect to the y-axis position and dynamically calculates the attenuation coefficient k based on the light intensity gradient of the boundary bright spot. Combined with an exponential normalization method, it corrects the light intensity of each pixel, effectively eliminating errors caused by uneven light intensity distribution and dispersion tilt in orthogonal dispersion systems. This processing step significantly improves interpolation consistency and spectral stitching accuracy, thus maintaining high measurement reliability even in complex optical environments.

[0008] 3. This invention utilizes the mapping relationship between pixels and wavelengths, inserting y-axis pixels between adjacent x-axis points to achieve seamless stitching of two-dimensional spectra into one-dimensional high-density spectral sequences. This technique fully leverages the free spectral range decomposition capability of the grating, significantly improving spectral resolution without sacrificing system stability, and is suitable for measurement requirements that require both ultra-large range and high precision.

[0009] 4. This invention separates the self-test calibration process from the spectral calibration process, achieving a rapid and repeatable calibration stage through an optical switch, significantly simplifying the operational complexity and time cost of traditional calibration processes. This method is easily integrated into practical industrial measurement systems, supports periodic or real-time calibration, and has good engineering applicability and promotional value. Attached Figure Description

[0010] Figure 1 This is a schematic diagram of the experimental system apparatus in this invention; Figure 2 This is a schematic diagram illustrating the principle of two-dimensional spectral dispersion in this invention. Figure 3 This is a schematic diagram of the calibration spectrum in this invention. Detailed Implementation

[0011] In this embodiment, a calibration device with spectral self-calibration function, such as... Figure 1 As shown, it includes: a narrowband light source 1, a broadband light source 2, an optical fiber isolator 3, a 1-to-2 coupler 4, a 2-to-2 coupler 5, an interference system, a first multiplexer 8 and a second multiplexer 9, an FP cavity 10, a first collimator 11, a second collimator 12, a third collimator 13, an orthogonal dispersion system, and a computer 21. The interference system includes: an interference system reference arm 6 and an interference system sample arm 7. The orthogonal dispersion system includes, in sequence: a cylindrical lens 14, a first reflecting mirror 15, a second reflecting mirror 16, a virtual phase array 17, a grating 18, a focusing lens 19, and an industrial camera 20.

[0012] Narrowband light source 1 is connected to port A of the first multiplexer 8 via optical fiber, and broadband light source 2 is connected in series via optical fiber to optical fiber isolator 3, upper outlet of 1-to-2 coupler 4, and port B of the first multiplexer 8. The C port of the first multiplexer 8 is connected in series with the first collimator 11, the FP cavity 10, the second collimator 12, and the A port of the second multiplexer 9 via optical fiber.

[0013] The lower outlet of the 1-to-2 coupler 4 is connected to the lower inlet of the 2-to-2 coupler 5 via optical fiber; the upper inlet of the 2-to-2 coupler 5 is connected to port B of the second multiplexer 9 via optical fiber; the first multiplexer 8 and the second multiplexer 9 are the core components for realizing fast switching between the three optical paths, and are typically magneto-optical switches or microelectro-optical switches, with switching times usually on the order of milliseconds. This design allows for rapid self-calibration before or during experiments, combating system drift.

[0014] The lower outlet of the 2-to-2 coupler 5 is connected to the interference system via an optical fiber; The C port of the second multiplexer 9 is connected in series with the third collimator 13 and the orthogonal dispersion system via optical fiber; When the narrowband light source path is selected, the A ports of the first multiplexer 8 and the second multiplexer 9 are selected, so that the narrowband light emitted by the narrowband light source 1 is collimated by the first collimator 11 after passing through the first multiplexer 8, and then enters the FP cavity 10. After being modulated by the FP cavity 10, the narrowband light is collimated again by the second collimator 12. The narrowband light after secondary collimation is emitted through the second multiplexer 9 and then collimated again by the third collimator 13. The narrowband light after tertiary collimation enters the cylindrical lens 14 for beam shaping. The shaped narrowband light is reflected by the first mirror 15 and the second mirror 16 in sequence, and then enters the virtual phase array 17 for vertical beam splitting, then enters the grating 18 for horizontal beam splitting, and finally enters the focusing lens 19 for convergence. The resulting narrowband two-dimensional dispersed light is received by the industrial camera 20 and generates a series of bright spots.

[0015] When the broadband light source path is activated, port B of the first multiplexer 8 and port A of the second multiplexer 9 are activated, so that the broadband light emitted from the broadband light source 2 passes sequentially through the fiber optic isolator 3 and the 1-to-2 coupler 4. The broadband light exiting from the upper outlet of the 1-to-2 coupler 4 passes through the first multiplexer 8 and is collimated in the first collimator 11 before entering the FP cavity 10. After being modulated by the FP cavity 10, the narrowband light is further collimated by the second collimator 12. The resulting broadband light, after being collimated twice, passes through the second... The beam emitted from the multiplexer 9 is collimated by the third collimator 13. The resulting broadband light, after being collimated three times, enters the cylindrical lens 14 for beam shaping. The shaped broadband light then passes through the first mirror 15 and the second mirror 16 in sequence before entering the virtual phase array 17 for vertical beam splitting. It then enters the grating 18 for horizontal beam splitting and finally enters the focusing lens 19 for convergence. The resulting broadband two-dimensional dispersive light is received by the industrial camera 20 and generates a CCD image containing multiple bright stripes.

[0016] When the interference system path is selected, port A of the first multiplexer 8 and port B of the second multiplexer 9 are selected, so that the broadband light emitted by the broadband light source 2 passes through the fiber isolator 3 and the lower outlet of the 1-to-2 coupler 4 in sequence and enters the 2-to-2 fiber coupler 5 for beam splitting. The two beams enter the reference arm 6 and the sample arm 7 of the interference system, respectively. The light returning from the reference arm 6 and the sample arm 7 of the interference system converges and interferes in the 2-to-2 fiber coupler 5. The resulting interference signal enters the collimator 13 for collimation through the second optical multiplexer 9. The collimated interference light then enters the cylindrical lens 14 for beam shaping. The shaped broadband light passes through the first reflector 15 and the second reflector 16 in sequence and enters the virtual phase array 17 for vertical beam splitting. Then it enters the grating 18 for horizontal beam splitting and finally enters the focusing lens 19 for convergence. The resulting two-dimensional dispersive interference light is received by the industrial camera 20 and produces an interference fringe pattern.

[0017] In this embodiment, a high-resolution spectral calibration method with spectral self-calibration function is applied to the above-mentioned calibration device and performed according to the following steps: Step 1: Use one column of bright spots as the baseline column. and from Find the pixel coordinates of the brightest point corresponding to the wavelength of narrowband light. and its light intensity ; benchmark column After the initial installation and debugging, it is usually fixed. The maximum light intensity is searched along the y-direction in this column, and its pixel coordinates are determined. This refers to the exact location of the reference wavelength under the current environment, and the light intensity. This is also recorded. This step is quick and simple, providing a stable wavelength reference origin for the entire calibration system. If the ambient temperature changes, repeating this step will yield a new reference. This compensates for drift.

[0018] Step 2: In the baseline column The brightest point in the CCD image is identified, along with the center points of the bright stripes corresponding to the brightest points and their adjacent center points. The y-coordinate of the center point of the first bright stripe is recorded. and its light intensity and the y-axis coordinate of the center point of the adjacent second bright fringe. and its light intensity Thus, the row containing the center point of the first bright fringe and the row containing the center point of the second bright fringe are respectively taken as the upper boundary and the lower boundary, and the area between the upper boundary and the lower boundary is taken as the boundary area. The light intensity gradient attenuation coefficient k of the virtual phase array 17 in the dispersion direction is calculated using equation (1): (1) The attenuation coefficient k, calculated according to equation (1), accurately describes the exponential decay of light intensity along the dispersion direction (y-axis) of the virtual phase array. This coefficient is used to correct the light intensity inhomogeneity caused by the virtual phase array in subsequent steps, ensuring the accuracy of spectral stitching.

[0019] Step 3: Use the boundary region to truncate the interference fringe pattern, and then rotate the truncated interference fringe pattern clockwise to compensate for the dispersion shift, thus obtaining the compensated interference fringe pattern. The compensated interference fringe pattern is sparsely sampled along the x-axis according to the grating period, generating a dimension of... The compressed data matrix; where m represents the number of rows in the boundary region, i.e., the number of effective pixels in one FSR period; n represents the number of columns after sparse sampling; Step 4: Process the compressed data matrix using two-dimensional spectral interferometry modulation, the principle of which is as follows: Figure 2 As shown: A precise mapping relationship between wavelength and pixels is established using two-dimensional dispersion-dimensional interference modulation theory, thereby finding the mapping relationship between wavelength and intensity. This is achieved by interpolating pixels in the vertical dispersion direction into the horizontal dispersion direction, resulting in a high-density one-dimensional spectral sequence.

[0020] Step 4.1: Define the current column index as... The current row number is Let the pivot column be the i-th column, and initialize i=1; Step 4.2: Initialization =1, initialize the first upper boundaries of behavior; Step 4.3: Calculate the first element in the compressed data matrix using equation (2). Liede row of pixels P ij Normalized light intensity : (2) In equation (2), For pixel P ij The measured light intensity For pixel P ij The y-axis coordinate; Step 4.4: [The text appears to be incomplete and contains several grammatical errors. A more accurate translation would require the full context.] Assign to Then, return to step 4.3 and execute sequentially until... up to n, thus obtaining the nth The normalized light intensity of all pixels in the column; Step 4.5: [The sentence is incomplete and requires more context to be translated accurately.] Assign to Then, return to step 4.2 and execute sequentially until... The algorithm continues until m is reached, thus obtaining the normalized light intensity of all pixels in all columns and stitching them together into a complete high-density one-dimensional spectral sequence. Steps 4.1 to 4.5 are the core loop algorithm for spectral stitching and normalization. Its purpose is to eliminate the light intensity attenuation caused by VIPA dispersion and stitch the two-dimensional data into a one-dimensional spectrum. It is a compensation factor that normalizes the light intensity of all pixels to the light intensity level at the reference point, thereby eliminating the inherent unevenness of light intensity distribution in the virtual phase array and ensuring the comparability of light intensity at different y positions.

[0021] Step 5: Calculate the wavelength value of any k-th data point in the high-density one-dimensional spectral sequence using equation (3). : (3) In equation (3), The reference wavelength corresponding to the broadband light source. This is expressed as a step of wavelength, and we have: (4) In equation (4), N is the number of effective pixels in one FSR cycle within the boundary region.

[0022] Step Six: Using the wavelength value corresponding to each data point in the high-density one-dimensional spectral sequence as the x-axis, ... Using the vertical axis as the ordinate, the spectrum of broadband light source 2 is thus calibrated, as shown below. Figure 3 As shown, plotting the light intensity-wavelength curve completes the high-resolution spectral calibration of the broadband light source. The resolution of the spectrum obtained by this method is determined by the high dispersion capability of the virtual phase array, which is far higher than that of traditional spectrometers. At the same time, due to the self-calibration process, its wavelength accuracy and long-term stability are also greatly guaranteed.

Claims

1. A calibration device with spectral self-calibration function, characterized in that, include: The system comprises a narrowband light source (1), a broadband light source (2), an optical fiber isolator (3), a 1-to-2 coupler (4), a 2-to-2 coupler (5), an interference system, a first multiplexer (8) and a second multiplexer (9), an FP cavity (10), a first collimator (11), a second collimator (12), a third collimator (13), an orthogonal dispersion system, and a computer (21). The interference system includes an interference system reference arm (6) and an interference system sample arm (7). The orthogonal dispersion system includes, in sequence, a cylindrical lens (14), a first mirror (15), a second mirror (16), a virtual phase array (17), a grating (18), a focusing lens (19), and an industrial camera (20). The narrowband light source (1) is connected to the A port of the first multiplexer (8) via an optical fiber, and the broadband light source (2) is connected in series via an optical fiber isolator (3), the upper outlet of the 1-to-2 coupler (4), and the B port of the first multiplexer (8). The C port of the first multiplexer (8) is connected in series with the first collimator (11), the FP cavity (10), the second collimator (12), and the A port of the second multiplexer (9) via optical fiber; The lower outlet of the 1-to-2 coupler (4) is connected to the lower inlet of the 2-to-2 coupler (5) via optical fiber; the upper inlet of the 2-to-2 coupler (5) is connected to the B port of the second multiplexer (9) via optical fiber. The lower outlet of the two-to-two coupler (5) is connected to the interference system via an optical fiber; The C port of the second multiplexer (9) is connected in series with the third collimator (13) and the orthogonal dispersion system via optical fiber; When the narrowband light source path is selected, the A ports of the first multiplexer (8) and the second multiplexer (9) are selected, so that the narrowband light emitted by the narrowband light source (1) is collimated by the first collimator (11) after passing through the first multiplexer (8), and then enters the FP cavity (10). After being modulated by the FP cavity (10), the narrowband light is collimated again by the second collimator (12). The resulting narrowband light after secondary collimation is emitted through the second multiplexer (9) to the third collimator (10). 13) After collimation, the narrowband light obtained after three collimations enters the cylindrical lens (14) for beam shaping. The shaped narrowband light is reflected by the first mirror (15) and the second mirror (16) in sequence, and then enters the virtual phase array (17) for vertical beam splitting, and then enters the grating (18) for horizontal beam splitting, and finally enters the focusing lens (19) for convergence. The resulting narrowband two-dimensional dispersion light is received by the industrial camera (20) and generates a series of bright spots. When the broadband light source path is activated, the B port of the first multiplexer (8) and the A port of the second multiplexer (9) are activated, so that the broadband light emitted by the broadband light source (2) passes through the fiber optic isolator (3) and the splitter coupler (4) in sequence. The broadband light emitted from the upper outlet of the splitter coupler (4) passes through the first multiplexer (8) and is collimated in the first collimator (11) before entering the FP cavity (10). After being modulated by the FP cavity (10), the narrowband light is collimated again by the second collimator (12). The resulting broadband light after secondary collimation passes through the first multiplexer (8) and then enters the FP cavity (10). The light is emitted through the second multiplexer (9) and collimated in the third collimator (13). The broadband light obtained after three collimations enters the cylindrical lens (14) for beam shaping. The shaped broadband light then passes through the first mirror (15) and the second mirror (16) for reflection in sequence, and then enters the virtual phase array (17) for vertical beam splitting. It then enters the grating (18) for horizontal beam splitting and finally enters the focusing lens (19) for convergence. The resulting broadband two-dimensional dispersion light is received by the industrial camera (20) and generates a CCD image containing multiple bright stripes. When the interference system path is selected, the A port of the first multiplexer (8) and the B port of the second multiplexer (9) are selected, so that the broadband light emitted by the broadband light source (2) passes through the fiber isolator (3) and the lower end of the splitter (4) in sequence and then enters the splitter fiber coupler (5) for beam splitting, resulting in two beams that enter the interference system reference arm (6) and the interference system sample arm (7) respectively; the light returning from the interference system reference arm (6) and the interference system sample arm (7) converges and interferes in the splitter fiber coupler (5), producing The interference signal is collimated in collimator (13) via optical second multiplexer (9). The collimated interference light then enters cylindrical lens (14) for beam shaping. The shaped broadband light is reflected by first mirror (15) and second mirror (16) in sequence, and then enters virtual phase array (17) for vertical beam splitting. It then enters grating (18) for horizontal beam splitting and finally enters focusing lens (19) for convergence. The resulting two-dimensional dispersive interference light is received by industrial camera (20) and generates interference fringe pattern.

2. A high-resolution spectral calibration method with spectral self-calibration function, characterized in that, It is applied to the calibration device as described in claim 1 and performed according to the following steps: Step 1: Use the aforementioned column of bright spots as the reference column. and from Find the pixel coordinates of the brightest point corresponding to the wavelength of narrowband light. and its light intensity ; Step 2: In the baseline column The brightest point in the CCD image is identified, along with the center points of the bright stripes corresponding to the brightest points and their adjacent center points. The y-coordinate of the center point of the first bright stripe is recorded. and its light intensity and the y-axis coordinate of the center point of the adjacent second bright fringe. and its light intensity Thus, the row containing the center point of the first bright fringe and the row containing the center point of the second bright fringe are respectively taken as the upper boundary and the lower boundary, and the area between the upper boundary and the lower boundary is taken as the boundary area. The light intensity gradient attenuation coefficient k of the virtual phase array (17) in the dispersion direction is calculated using equation (1): (1) Step 3: Use the boundary region to truncate the interference fringe pattern, and then perform dispersion shift compensation on the truncated interference fringe pattern by rotating it clockwise to obtain the compensated interference fringe pattern. The compensated interference fringe pattern is sparsely sampled along the x-axis according to the grating period, generating a dimension of... The compressed data matrix; where m represents the number of rows in the boundary region, i.e., the number of effective pixels in one FSR period; n represents the number of columns after sparse sampling; Step 4: Process the compressed data matrix using two-dimensional spectral interferometry modulation to obtain a high-density one-dimensional spectral sequence; Step 4.1: Define the current column index as... The current row number is Let the pivot column be the i-th column, and initialize i=1; Step 4.2: Initialization =1, initialize the first upper boundaries of behavior; Step 4.3: Calculate the first element in the compressed data matrix using equation (2). Liede row of pixels P ij Normalized light intensity : (2) In equation (2), For pixel P ij The measured light intensity For pixel P ij The y-axis coordinate; Step 4.4: [The text appears to be incomplete and contains several grammatical errors. A more accurate translation would require Assign to Then, return to step 4.3 and execute sequentially until... up to n, thus obtaining the nth The normalized light intensity of all pixels in the column; Step 4.5: [The sentence is incomplete and requires more context to be translated accurately.] Assign to Then, return to step 4.2 and execute sequentially until... Up to m, the normalized light intensity of all pixels in all columns is obtained and stitched together to form a complete high-density one-dimensional spectral sequence; Step 5: Calculate the wavelength value of any k-th data point in the high-density one-dimensional spectral sequence using equation (3). : (3) In equation (3), The reference wavelength corresponding to the broadband light source. This is expressed as a step of wavelength, and we have: (4) In equation (4), N is the number of effective pixels in one FSR cycle within the boundary region; Step Six: Using the wavelength value corresponding to each data point in the high-density one-dimensional spectral sequence as the x-axis, ... The vertical axis is used to calibrate the spectrum of the broadband light source (2).

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