CN115950890B - Spectral domain optical coherence tomography detection method and system for industrial detection - Google Patents
Spectral domain optical coherence tomography detection method and system for industrial detection Download PDFInfo
- Publication number
- CN115950890B CN115950890B CN202310248715.8A CN202310248715A CN115950890B CN 115950890 B CN115950890 B CN 115950890B CN 202310248715 A CN202310248715 A CN 202310248715A CN 115950890 B CN115950890 B CN 115950890B
- Authority
- CN
- China
- Prior art keywords
- sample
- coherence tomography
- optical coherence
- spectral domain
- unit
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Landscapes
- Investigating Or Analysing Materials By Optical Means (AREA)
Abstract
The invention relates to a spectral domain optical coherence tomography detection method and a system for industrial detection, wherein the system is used for realizing the following steps: s1, constructing a spectral domain optical coherence tomography detection system; s2, performing distortion calibration on a spectral domain optical coherence tomography detection system; s3, placing the sample to be tested on a sample bearing unit; s4, the sample bearing unit drives the sample to be detected to move, and the spectral domain optical coherence tomography unit scans the sample to be detected and acquires a 3D original chromatographic signal of the sample to be detected; s5, performing data processing on the 3D original chromatographic signal by an image processing unit to obtain an optical coherence tomography 3D image of the sample to be detected; s6, analyzing the optical coherence tomography 3D image by the defect classification unit and outputting a detection result. According to the invention, the distortion influence of the optical system is eliminated through the post-processing of the computer, so that the system is ensured to obtain 3D chromatographic structure information with large visual field and high resolution and more accurate defect detection and classification results.
Description
Technical Field
The invention relates to the field of optical detection, in particular to a spectral domain optical coherence tomography detection method and a spectral domain optical coherence tomography detection system for industrial detection.
Background
Along with the improvement of technological development and consumption level, the evolution of various products is daily and monthly. New materials, new processes and new designs endow products with new functions, and higher requirements on the quality detection and control of the products are also provided.
At present, the detection means is mainly a manual visual detection mode. A large number of people perform detection in a factory workshop in a labor-intensive manner, and in order to ensure no leakage and no erroneous judgment, a deep inspector called a 'golden eye' needs to re-judge the product after initial inspection. However, the manual visual detection method has the defects of inconsistent detection standards, low efficiency, susceptibility to subjective factors and the like besides a large amount of manual stacking, and is difficult to meet the actual industrial production requirements.
The traditional machine vision technology and automatic optical detection technology simulate human eyes by using a lens group, obtain a two-dimensional image of an object to be detected, further identify defects by using an image processing technology, and judge whether a product is qualified or not. However, with rapid development of materials, designs and color diversity of various new products, the conventional 2D data-based automatic optical detection technology cannot meet the requirements of industrial quality inspection, high-speed acquisition of 3D structural information of samples, and algorithm of new data analysis and defect analysis.
Currently, the mainstream 3D measurement technology includes binocular stereo vision, time-of-flight, speckle measurement, and structured light methods. All that is obtained by the 3D detection method is the surface morphology information of the sample. However, with the rapid development of the related art for 3C-type products, the demand for chromatographic 3D defect detection of transparent, semitransparent, or highly scattering structured products is increasing.
Currently, there are two main techniques for achieving tomography: optical coherence tomography and dispersive confocal microscopy. The latter, however, has the following significant drawbacks: (1) The imaging sensitivity is low, and weak defect signals cannot be identified; (2) the design of the dispersion lens is extremely complex; (3) the detection speed is slow. Thus, optical coherence tomography has so far been the only effective technical route to achieve high quality tomography.
Optical coherence tomography, which is born in the 90 s of the last century, is a low coherence optical interference imaging technology based on a spectrum broadband light source. The technology measures scattered/reflected light signals at different depths inside the sample by an optical interference method, thereby realizing three-dimensional 'tomography' imaging of the inside of the sample to be detected. The optical coherence tomography is a nondestructive detection technology, has the characteristics of high sensitivity, high speed, large visual field, high precision and the like, and is very suitable for imaging and measuring high-scattering samples and transparent and semitransparent multilayer structures. Optical coherence tomography is currently in the biomedical field, especially ophthalmology, with very wide and irreplaceable applications. At present, optical coherence tomography is also applied to industrial scenes in a small amount, such as internal defects of lens groups, internal defects of liquid crystal screens, different thicknesses of tablet medicines, 3D morphological defects on the surface of a printed circuit board and the like.
Conventional SD-OCT adopts a confocal detection method. When the device is used for sample detection, a 2D scanning galvanometer on a sample arm is required to be used for carrying out point scanning along the surface, an optical fiber at a receiving end forms a small aperture diaphragm due to a tiny aperture (micron order), and forms a confocal imaging system together with a collimator system and a focusing objective system in the sample arm. However, unlike the field of industrial detection for medical applications, there are extremely high requirements on lateral resolution, imaging depth and field of view, and thus stringent requirements are placed on the beam scanning system and focusing system. In a practical application scene, distortion of a scanning system and a focusing imaging system and an adjustment error are difficult to be completely eliminated through hardware optimization and adjustment, and imaging quality is seriously affected.
The conventional adaptive optics technology is mainly implemented by hardware, such as a Shack-Hartmann wavefront sensor is used to acquire wave surface phase information, and a deformable mirror is used to calibrate corresponding wave surface distortion. However, the conventional technology has the following disadvantages: the system has the advantages of high cost, complex structure, low speed, large occupied space of the system and incapability of processing complex wave surface distortion conditions.
Disclosure of Invention
The first object of the invention is to provide a spectral domain optical coherence tomography detection method for industrial detection, which eliminates the distortion influence of an optical system through computer post-processing, and ensures that the system obtains 3D chromatographic structure information with large visual field and high resolution and more accurate defect detection and classification results.
The technical scheme for realizing the first purpose of the invention is as follows: the spectral domain optical coherence tomography detection method for industrial detection comprises the following steps:
s1, constructing a spectral domain optical coherence tomography detection system; the spectral domain optical coherence tomography detection system comprises a spectral domain optical coherence tomography unit, a sample bearing unit, an image processing unit and a defect classification unit; the sample bearing unit comprises a bearing platform for placing a transparent or semitransparent or high-scattering sample to be detected and a driving mechanism for driving the bearing platform to move in the vertical direction and move in the 2D (two-dimensional) direction on the horizontal plane;
s2, performing distortion calibration on a spectral domain optical coherence tomography detection system;
s3, placing a transparent or semitransparent or high scattering sample to be detected on a bearing platform of a sample bearing unit, and enabling the sample to be detected to be located in a detection area;
s4, a driving mechanism of the sample bearing unit drives a sample to be detected on the bearing platform to move, and the spectral domain optical coherence tomography unit performs 2D point scanning on the sample to be detected to acquire a depth signal of a single point position in the scanning beam direction, so that a 3D original tomography signal of the sample to be detected is acquired and transmitted to the image processing unit;
s5, after the image processing unit receives the 3D original chromatographic signal, performing data processing including calculation of adaptive optics emission on the 3D original chromatographic signal to obtain an optical coherence tomography 3D image of the complete 3D space dimension of the sample to be detected, and then transmitting the optical coherence tomography 3D image to the defect classification unit;
s6, analyzing the optical coherence tomography 3D image by using a defect classification unit, identifying and classifying defects of each region to be detected on the sample to be detected, and outputting a detection result.
Further, the step of distortion calibration in the step S2 is as follows:
A. placing a resolution calibration plate on a bearing platform and locating in a detection area;
B. the spectral domain optical coherence tomography unit is adjusted to enable the spectral domain optical coherence tomography unit to clearly image the resolution calibration plate near the focal plane of the first lens group of the sample arm;
C. changing the resolution calibration plate into a standard sample; the standard sample is a suspension liquid composed of scattering particles with a dimension smaller than the transverse and longitudinal resolution of the spectral domain optical coherence tomography unit and water;
D. scanning and imaging the standard sample by using a spectral domain optical coherence tomography unit to obtain the standard sample3D raw data s of spectral domain optical coherence tomography 0 (x, y, k); wherein x, y is the space coordinate of the horizontal dimension, and k is the wave number coordinate of the spectrum dimension;
E. for 3D original data s 0 (x, y, k) performing a two-dimensional Fourier transform in the x, y direction to obtain 3D data
Wherein Q is x ，Q y Spatial frequency coordinates corresponding to the x, y dimensions;
F. 3D data is processed
And a phase factor for calibrating the overall aberration of the spectral domain optical coherence tomography unit>
Multiplying to obtain 3D data after phase modulation>
Wherein k is c Is the center wavelength lambda of the spectrum of the light source 0 The corresponding wave number, ψ (Q x ，Q y ) Is a 2D function physically meant as phase; the specific values of this 2D function are determined by the following procedure and criteria; i is an imaginary unit, and i=sqrt (-1);
G. for 3D data after phase modulation
Performing 3D Fourier transform to obtain 3D image data I 1 (x, y, z), wherein z is a spatial coordinate perpendicular to the x, y direction;
H. select I 1 A data cross section at the focal plane of the first lens group of the sample arm at a spatial position in (x, y, z); finding a sharp image of a particle P in the suspension (where the density of particles in the suspension is high, so that a sharp image of a particle P can always be found in the data cross section), rounding the center of gravity of the image of the particle P with the origin, and covering the image of the whole particle PAn image containing no other particles, the area of the circle being A 0 The method comprises the steps of carrying out a first treatment on the surface of the Then calculate the area A occupied by the image of particle P at its semi-high intensity location 1 And A is with 0 Is defined by the ratio of: r=a 1 /A 0 ；
I. Continuously adjusts the 2D function ψ (Q x ，Q y ) So that the image of the particle P becomes sharp until the value of the ratio r takes the minimum value, ψ (Q x ，Q y ) And obtaining an optimal distortion compensation result, and finally realizing distortion calibration.
Further, the spectral domain optical coherence tomography detection system is used for synchronously controlling the drawing of the spectral domain optical coherence tomography unit and the driving mechanism of the sample bearing unit so as to carry out horizontal block imaging on the sample to be detected; the 3D original chromatographic signal used for dividing blocks is transmitted to the image processing unit; and the image processing unit is used for splicing the segmented 3D original tomographic signals to obtain an optical coherence tomographic 3D image with the complete 3D space dimension.
Further, the image processing unit processes the segmented 3D original tomographic signals to form segmented 3D images, and transmits the segmented 3D images to the defect classification unit; and the defect classification unit analyzes the segmented 3D image to obtain defect types, and synthesizes the defect information of each segment to form the total defect information of the sample to be detected.
The second object of the present invention is to provide a spectral domain optical coherence tomography detection system for implementing the detection method, which can effectively solve the difficult problems of increased cost, increased complexity, slow calibration speed, reduced system stability and the like possibly caused by the traditional hardware compensation.
The technical scheme for realizing the second purpose of the invention is as follows: the spectral domain optical coherence tomography detection system for industrial detection has the spectral domain optical coherence tomography detection system for realizing the steps S2 to S6.
The spectral domain optical coherence tomography unit is an optical fiber interferometer and comprises a spectral broadband light source, an optical fiber coupler, a sample arm, a reference arm, a spectrometer, a data acquisition unit and a synchronous control unit; the spectrum broadband light source is used for emitting low-coherence light; the optical fiber coupler is used for dividing the low-coherence light into two beams to be respectively incident to the sample arm and the reference arm; the sample arm collimates the optical signals in the optical fibers into parallel light, focuses the parallel light onto a sample to be measured through the deflection device and the first lens group, is simultaneously provided with a coaxial indication visible light source, a coaxial visible illumination light source and a surface scanning camera, and is simultaneously provided with a first optical fiber polarization controller to adjust the polarization state of the optical signals incident to the sample to be measured; the reference arm collimates the optical signals in the optical fiber into parallel light, focuses the parallel light on the reflecting plane mirror through the second lens group, is simultaneously provided with a diaphragm capable of adjusting light intensity, and is provided with a second optical fiber polarization controller to adjust the polarization state of the optical signals in the reference arm; the return light of the sample arm and the reference arm interfere on the fiber-optic coupler; the optical interference signal in the optical fiber is collimated into parallel light by the spectrometer, the parallel light is incident to the grating for diffraction, the diffracted light is focused to the line scanning camera by the third lens group for photoelectric conversion so as to obtain a modulation spectrum of the optical interference signal, and meanwhile, a third optical fiber polarization controller is assembled so as to adjust the polarization state of light irradiated to the grating; the data acquisition unit converts an analog electronic signal output by the spectrometer into a digital signal; the synchronous control unit outputs a multi-path control signal to synchronously adjust the acquisition process of the spectrometer, the light deflection process of the sample arm, the movement process of the sample to be detected of the sample bearing unit and the data processing and display process of the image processing unit.
The 3D original chromatographic signals are a 2D space signal and a 1D spectral domain signal, and the 1D spectral domain signal corresponds to the space signal in the 1D depth direction.
The invention has the positive effects that:
(1) The invention can realize the high-precision, large-visual-field and high-sensitivity 3D imaging of the high-scattering sample and the transparent and semitransparent multilayer structure sample in the industrial field, and can realize the positioning and type identification of defects with different depths.
(2) The invention can effectively solve the problem of degradation of the system transverse resolution caused by optical distortion in the light beam scanning system, and ensure the imaging quality of the system. And the problems of possibly increased cost, increased system complexity, low calibration speed, reduced system stability and the like of the system caused by the traditional hardware compensation can be effectively solved. The method also has great flexibility and can conveniently deal with the optical distortion problem of any other imaging system.
(3) The invention applies the computational self-adaptive optical technology to the 3D nondestructive industrial defect detection system based on the spectral domain optical coherence tomography technology, eliminates the distortion influence of the optical system through the post-processing of the computer, and ensures that the system obtains the 3D chromatographic structure information with large visual field and high resolution and more accurate defect detection and classification results.
Drawings
In order that the invention may be more readily understood, a more particular description of the invention will be rendered by reference to specific embodiments thereof which are illustrated in the appended drawings, in which
FIG. 1 is a schematic diagram of the structure of a spectral domain optical coherence tomography unit in the present invention;
FIG. 2 is a schematic view of a sample carrying unit according to the present invention;
fig. 3 is a front view of a sample carrier unit according to the present invention.
Detailed Description
Example 1
The spectral domain optical coherence tomography detection method for industrial detection comprises the following steps:
s1, constructing a spectral domain optical coherence tomography detection system; the spectral domain optical coherence tomography detection system comprises a spectral domain optical coherence tomography unit 1, a sample bearing unit 2, an image processing unit 3 and a defect classification unit 4; the sample carrying unit 2 comprises a carrying platform 2-1 for placing a transparent or semitransparent or high scattering sample 1-6 to be detected and a driving mechanism for driving the carrying platform 2-1 to move in the vertical direction and 2D on the horizontal plane;
s2, performing distortion calibration on a spectral domain optical coherence tomography detection system;
s3, placing the transparent or semitransparent or high scattering sample 1-6 to be detected on a bearing platform 2-1 of a sample bearing unit 2, and enabling the sample 1-6 to be detected to be located in a detection area;
s4, a driving mechanism of the sample bearing unit 2 drives the sample 1-6 to be detected on the bearing platform 2-1 to move, and the spectral domain optical coherence tomography unit 1 performs 2D point scanning on the sample 1-6 to be detected to acquire a depth signal of a single point position in the scanning beam direction, so as to acquire a 3D original tomography signal of the sample 1-6 to be detected and transmit the 3D original tomography signal to the image processing unit 3;
s5, after receiving the 3D original chromatographic signal, the image processing unit 3 performs data processing including calculation of adaptive optics emission to obtain an optical coherence tomography 3D image of the complete 3D space dimension of the sample 1-6 to be detected, and then the optical coherence tomography 3D image is transmitted to the defect classification unit 4;
s6, analyzing the optical coherence tomography 3D image by the defect classification unit 4, identifying and classifying defects of each region to be detected on the samples 1-6 to be detected, and outputting detection results.
The step of distortion calibration in the step S2 is as follows:
A. placing a resolution calibration plate on the bearing platform 2-1 and being positioned in a detection area;
B. the spectral domain optical coherence tomography unit 1 is adjusted to enable the spectral domain optical coherence tomography unit to clearly image the resolution calibration plate near the focal plane of the first lens group 1-3-4 of the sample arm 1-3;
C. changing the resolution calibration plate into a standard sample; the standard sample is a suspension liquid composed of scattering particles with a dimension smaller than the transverse and longitudinal resolutions of the spectral domain optical coherence tomography unit 1 and water;
D. the spectral domain optical coherence tomography unit 1 scans and images a standard sample to obtain 3D original data s of spectral domain optical coherence tomography of the standard sample 0 (x, y, k); wherein x, y is the space coordinate of the horizontal dimension, and k is the wave number coordinate of the spectrum dimension;
E. for 3D original data S 0 (x, y, k) performing a two-dimensional Fourier transform in the x, y direction to obtain 3D data
Wherein Q is x ，Q y Spatial frequency coordinates corresponding to the x, y dimensions;
F. 3D data is processed
And a phase factor for calibrating the overall aberration of the spectral domain optical coherence tomography unit 1>
Multiplying to obtain 3D data after phase modulation>
Wherein k is c Is the center wavelength lambda of the spectrum of the light source 0 The corresponding wave number, ψ (Q x ，Q y ) Is a 2D function physically meant as phase; the specific values of this 2D function are determined by the following procedure and criteria; i is an imaginary unit, and i=sqrt (-1);
G. for 3D data after phase modulation
Performing 3D Fourier transform to obtain 3D image data I 1 (x, y, z), wherein z is a spatial coordinate perpendicular to the x, y direction;
H. select I 1 A data cross section at the focal plane of the first lens group 1-3-4 of the sample arm 1-3 at a spatial position in (x, y, z); finding a sharp image of a particle P in the suspension (where the density of the particles in the suspension is high, so that a sharp image of a particle P can always be found in the data cross section), taking the center of gravity of the image of the particle P as the origin as a circle, and covering the image of the whole particle P and not containing the image of other particles, the area of the circle being A 0 The method comprises the steps of carrying out a first treatment on the surface of the Then calculate the area A occupied by the image of particle P at its semi-high intensity location 1 And A is with 0 Is defined by the ratio of: r=a 1 /A 0 ；
I. Continuously adjusts the 2D function ψ (Q x ，Q y ) Number of (2)The value is such that the image of the particle P becomes sharp until the value of the ratio r takes a minimum value, ψ (Q x ，Q y ) And obtaining an optimal distortion compensation result, and finally realizing distortion calibration.
The spectral domain optical coherence tomography detection system is used for synchronously controlling the drawing of the spectral domain optical coherence tomography unit 1 and the driving mechanism of the sample bearing unit 2 so as to carry out horizontal block imaging on the samples 1-6 to be detected; for transmitting the segmented 3D raw tomographic signal to the image processing unit 3; the image processing unit 3 performs stitching on the segmented 3D original tomographic signals to obtain an optical coherence tomographic 3D image with a complete 3D space dimension.
The spectral domain optical coherence tomography detection system for industrial detection has the spectral domain optical coherence tomography detection system for realizing the steps S2 to S6.
Referring to fig. 2 and 3, a sample carrying unit 2 in the invention comprises a carrying platform 2-1 for placing a sample 1-6 to be measured, a manual vertical translation stage 2-4 for driving the carrying platform 2-1 to move vertically and accurately, and an automatic horizontal translation stage 2-3 for driving the carrying platform 2-1 and the vertical translation stage 2-4 to move horizontally and accurately in any arbitrary direction, wherein the driving mode of the automatic horizontal translation stage 2-3 is motor driving, and the driving structure can refer to the existing cross translation stage; while the sample carrying unit 2 further comprises an adapter plate 2-2 for connecting the vertical translation stage 2-4 and the automatic horizontal translation stage 2-3.
The spectral domain optical coherence tomography unit 1 is an optical fiber type interferometer and comprises a spectral broadband light source 1-1, an optical fiber coupler 1-2, a sample arm 1-3, a reference arm 1-4, a spectrometer 1-5 data acquisition unit 1-7 and a synchronous control unit; the spectrum broadband light source 1-1 is used for emitting low-coherence light; the optical fiber coupler 1-2 is used for dividing low-coherence light into two beams to be respectively incident to the sample arm 1-3 and the reference arm 1-4; the sample arm 1-3 collimates the optical signals 1-3-2 in the optical fibers into parallel light, focuses the parallel light onto the sample 1-6 to be measured through the deflection device 1-3-3 and the first lens group 1-3-4, is simultaneously provided with a coaxial indication visible light source, a coaxial visible illumination light source and a surface scanning camera, and is simultaneously provided with the first optical fiber polarization controller 1-3-1 to adjust the polarization state of the optical signals incident on the sample 1-6 to be measured; the reference arm 1-4 collimates the optical signal 1-4-2 in the optical fiber into parallel light, focuses the parallel light on the reflecting plane mirror 1-4-4 through the second lens group 1-4-3, is simultaneously provided with a diaphragm capable of adjusting the light intensity, and is provided with the second optical fiber polarization controller 1-4-1 to adjust the polarization state of the optical signal in the reference arm 1-4; the return light of the sample arm 1-3 and the reference arm 1-4 interfere on the fiber coupler 1-2; the spectrometer 1-5 collimates the optical interference signal 1-5-5 in the optical fiber into parallel light to be incident on the grating 1-5-4 for diffraction, the third lens group 1-5-3 focuses the diffracted light to the line scanning camera 1-5-2 for photoelectric conversion to obtain a modulation spectrum of the optical interference signal, and meanwhile, the third optical fiber polarization controller 1-5-1 is assembled to adjust the polarization state of the light irradiated on the grating 1-5-4; the data acquisition unit 1-7 converts the analog electronic signals output by the spectrometer 1-5 into digital signals; the synchronous control unit outputs a multi-path control signal to synchronously adjust the acquisition process of the spectrometer 1-5, the light deflection process of the sample arm 1-3, the movement process of the sample 1-6 to be detected of the sample bearing unit 2 and the data processing and display process of the image processing unit 3.
The 3D original chromatographic signals are a 2D space signal and a 1D spectral domain signal, and the 1D spectral domain signal corresponds to the space signal in the 1D depth direction.
Example 2
The image processing unit 3 can also process the segmented 3D original chromatographic signal to form a segmented 3D image, and the segmented 3D image is transmitted to the defect classification unit 4; the defect classification unit 4 analyzes the segmented 3D image to obtain defect types, and synthesizes the defect information of each segment to form the total defect information of the samples 1-6 to be detected.
Other technical features are the same as those of embodiment 1.
While the foregoing is directed to embodiments of the present invention, other and further details of the invention may be had by the present invention, it should be understood that the foregoing description is merely illustrative of the present invention and that no limitations are intended to the scope of the invention, except insofar as modifications, equivalents, improvements or modifications are within the spirit and principles of the invention.
Claims (6)
1. The spectral domain optical coherence tomography detection method for industrial detection is characterized by comprising the following steps of:
s1, constructing a spectral domain optical coherence tomography detection system; the spectral domain optical coherence tomography detection system comprises a spectral domain optical coherence tomography unit, a sample bearing unit, an image processing unit and a defect classification unit; the sample bearing unit comprises a bearing platform for placing a transparent or semitransparent or high-scattering sample to be detected and a driving mechanism for driving the bearing platform to move in the vertical direction and move in the 2D (two-dimensional) direction on the horizontal plane;
s2, performing distortion calibration on a spectral domain optical coherence tomography detection system;
s3, placing a transparent or semitransparent or high scattering sample to be detected on a bearing platform of a sample bearing unit, and enabling the sample to be detected to be located in a detection area;
s4, a driving mechanism of the sample bearing unit drives a sample to be detected on the bearing platform to move, and the spectral domain optical coherence tomography unit performs 2D point scanning on the sample to be detected to acquire a depth signal of a single point position in the scanning beam direction, so that a 3D original tomography signal of the sample to be detected is acquired and transmitted to the image processing unit;
s5, after the image processing unit receives the 3D original chromatographic signal, performing data processing including calculation of adaptive optics emission on the 3D original chromatographic signal to obtain an optical coherence tomography 3D image of the complete 3D space dimension of the sample to be detected, and then transmitting the optical coherence tomography 3D image to the defect classification unit;
s6, analyzing the optical coherence tomography 3D image by a defect classification unit, identifying and classifying defects of each region to be detected on the sample to be detected, and outputting a detection result;
the step of distortion calibration in the step S2 is as follows:
A. placing a resolution calibration plate on a bearing platform and locating in a detection area;
B. the spectral domain optical coherence tomography unit is adjusted to enable the spectral domain optical coherence tomography unit to clearly image the resolution calibration plate near the focal plane of the first lens group of the sample arm;
C. changing the resolution calibration plate into a standard sample; the standard sample is a suspension liquid composed of scattering particles with a dimension smaller than the transverse and longitudinal resolution of the spectral domain optical coherence tomography unit and water;
D. scanning and imaging the standard sample by a spectral domain optical coherence tomography unit to obtain 3D original data S of spectral domain optical coherence tomography of the standard sample 0 (x, y, k); wherein x, y is the space coordinate of the horizontal dimension, and k is the wave number coordinate of the spectrum dimension;
E. for 3D original data S 0 (x, y, k) performing a two-dimensional Fourier transform in the x, y direction to obtain 3D data
Wherein Qx, qy correspond to the spatial frequency coordinates in the x, y dimensions;
F. 3D data is processed
And a phase factor for calibrating the overall aberration of the spectral domain optical coherence tomography unit
Multiplying to obtain 3D data after phase modulation>
Wherein k is c Is the center wavelength lambda of the spectrum of the light source 0 The corresponding wave number, ψ (Q x ，Q y ) Is a 2D function physically meant as phase; the specific values of this 2D function are determined by the following procedure and criteria; i is an imaginary unit, and i=sqrt (-1);
G. for 3D data after phase modulation
Making 3D FourierTransformation can obtain 3D image data I 1 (x, y, z), wherein z is a spatial coordinate perpendicular to the x, y direction;
H. select I 1 A data cross section at the focal plane of the first lens group of the sample arm at a spatial position in (x, y, z); finding a clear image of a particle P in the suspension, taking the center of gravity of the image of the particle P as the origin as a circle, and covering the image of the whole particle P and not containing other particles, wherein the area of the circle is A 0 The method comprises the steps of carrying out a first treatment on the surface of the Then calculate the area A occupied by the image of particle P at its semi-high intensity location 1 And A is with 0 Is defined by the ratio of: r=a 1 /A 0 ；
I. Continuously adjusts the 2D function ψ (Q x ，Q y ) So that the image of the particle P becomes sharp until the value of the ratio r takes the minimum value, ψ (Q x ，Q y ) And obtaining an optimal distortion compensation result, and finally realizing distortion calibration.
2. The spectral domain optical coherence tomography method for industrial detection of claim 1, wherein: the spectral domain optical coherence tomography detection system is used for synchronously controlling the drawing of the spectral domain optical coherence tomography unit and the driving mechanism of the sample bearing unit so as to carry out horizontal block imaging on the sample to be detected; the 3D original chromatographic signal used for dividing blocks is transmitted to the image processing unit; and the image processing unit is used for splicing the segmented 3D original tomographic signals to obtain an optical coherence tomographic 3D image with the complete 3D space dimension.
3. The spectral domain optical coherence tomography method for industrial detection of claim 2, wherein: the image processing unit processes the segmented 3D original chromatographic signals to form segmented 3D images, and transmits the segmented 3D images to the defect classification unit; and the defect classification unit analyzes the segmented 3D image to obtain defect types, and synthesizes the defect information of each segment to form the total defect information of the sample to be detected.
4. A spectral domain optical coherence tomography detection system for industrial detection, characterized in that: having a spectral domain optical coherence tomography detection system for implementing the steps S2 to S6 of claim 1.
5. A spectral domain optical coherence tomography system for industrial detection according to claim 4, wherein: the spectral domain optical coherence tomography unit is an optical fiber type interferometer and comprises a spectral broadband light source, an optical fiber coupler, a sample arm, a reference arm, a spectrometer, a data acquisition unit and a synchronous control unit; the spectrum broadband light source is used for emitting low-coherence light; the optical fiber coupler is used for dividing the low-coherence light into two beams to be respectively incident to the sample arm and the reference arm; the sample arm collimates the optical signals in the optical fibers into parallel light, focuses the parallel light onto a sample to be measured through the deflection device and the first lens group, is simultaneously provided with a coaxial indication visible light source, a coaxial visible illumination light source and a surface scanning camera, and is simultaneously provided with a first optical fiber polarization controller to adjust the polarization state of the optical signals incident to the sample to be measured; the reference arm collimates the optical signals in the optical fiber into parallel light, focuses the parallel light on the reflecting plane mirror through the second lens group, is simultaneously provided with a diaphragm capable of adjusting light intensity, and is provided with a second optical fiber polarization controller to adjust the polarization state of the optical signals in the reference arm; the return light of the sample arm and the reference arm interfere on the fiber-optic coupler; the optical interference signal in the optical fiber is collimated into parallel light by the spectrometer, the parallel light is incident to the grating for diffraction, the diffracted light is focused to the line scanning camera by the third lens group for photoelectric conversion so as to obtain a modulation spectrum of the optical interference signal, and meanwhile, a third optical fiber polarization controller is assembled so as to adjust the polarization state of light irradiated to the grating; the data acquisition unit converts an analog electronic signal output by the spectrometer into a digital signal; the synchronous control unit outputs a multi-path control signal to synchronously adjust the acquisition process of the spectrometer, the light deflection process of the sample arm, the movement process of the sample to be detected of the sample bearing unit and the data processing and display process of the image processing unit.
6. A spectral domain optical coherence tomography system for industrial detection according to claim 4, wherein: the 3D original tomographic signal is a 2D spatial signal and a 1D spectral domain signal, the 1D spectral domain signal corresponding to the spatial signal in the 1D depth direction.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310248715.8A CN115950890B (en) | 2023-03-15 | 2023-03-15 | Spectral domain optical coherence tomography detection method and system for industrial detection |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310248715.8A CN115950890B (en) | 2023-03-15 | 2023-03-15 | Spectral domain optical coherence tomography detection method and system for industrial detection |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN115950890A CN115950890A (en) | 2023-04-11 |
| CN115950890B true CN115950890B (en) | 2023-05-23 |
Family
ID=85891448
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202310248715.8A Active CN115950890B (en) | 2023-03-15 | 2023-03-15 | Spectral domain optical coherence tomography detection method and system for industrial detection |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN115950890B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117607155B (en) * | 2024-01-24 | 2024-04-19 | 山东大学 | Strain gauge appearance defect detection method and system |
| CN117870574B (en) * | 2024-03-13 | 2024-05-14 | 广东普洛宇飞生物科技有限公司 | Laser optical device capable of correcting in real time and correction method thereof |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7391520B2 (en) * | 2005-07-01 | 2008-06-24 | Carl Zeiss Meditec, Inc. | Fourier domain optical coherence tomography employing a swept multi-wavelength laser and a multi-channel receiver |
| CN103070665B (en) * | 2012-10-12 | 2015-05-20 | 中国科学院光电技术研究所 | Self-adapted sweep frequency optical coherence tomography imaging system based on double wave-front correctors |
| CN103932679B (en) * | 2014-04-09 | 2017-01-25 | 天津大学 | Image correcting method for thin layer chromatography imaging system |
| CN104523239B (en) * | 2015-01-12 | 2017-02-22 | 南京理工大学 | Full-depth spectral domain optical coherent tomography device and method |
| US20180172425A1 (en) * | 2016-12-21 | 2018-06-21 | The Penn State Research Foundation | High definition optical coherence tomography imaging for non-invasive examination of heritage works |
| CN112168144B (en) * | 2020-10-16 | 2022-12-20 | 佛山科学技术学院 | Optical coherence tomography system for burned skin |
| CN115078299B (en) * | 2022-02-22 | 2024-05-31 | 北京工业大学 | Terahertz computed tomography three-dimensional imaging method based on galvanometer scanning system |
-
2023
- 2023-03-15 CN CN202310248715.8A patent/CN115950890B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN115950890A (en) | 2023-04-11 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN115950890B (en) | Spectral domain optical coherence tomography detection method and system for industrial detection | |
| CN111220090A (en) | Line focusing differential color confocal three-dimensional surface topography measuring system and method | |
| US4838679A (en) | Apparatus for, and method of, examining eyes | |
| TWI794416B (en) | Metrology of multi-layer stacks and interferometer system | |
| CN102494623B (en) | Measuring method of non-contact measuring device of center to center distance of lens optical surfaces | |
| US7659991B2 (en) | Colorimetric three-dimensional microscopy | |
| CN104792272B (en) | Optical interference device for online real-time thickness detection | |
| CN111288902B (en) | Double-field-of-view optical coherence tomography imaging system and material thickness detection method | |
| US9239237B2 (en) | Optical alignment apparatus and methodology for a video based metrology tool | |
| JP2017198491A (en) | Film thickness measurement device and film thickness measurement method | |
| CN211876977U (en) | Line focusing differential color confocal three-dimensional surface topography measuring system | |
| CN106770287B (en) | A kind of one camera balanced type optical coherence tomography scanning means and method | |
| CN103148800A (en) | Label-free three-dimensional microscope method based on light filed propagation and device | |
| WO2018072447A1 (en) | Differential interference-based optical film defect detection method | |
| CN113566733A (en) | Line laser vision three-dimensional scanning device and method | |
| CN115541602B (en) | Product defect detection method | |
| TWI357973B (en) | Apparatus and method for simulataneous confocal fu | |
| CN214173285U (en) | Face type detecting system | |
| CN108692676A (en) | The three-dimensional shape measuring method of sweep type white interference microscope is used | |
| JP2012220224A (en) | Method and device for measuring unevenness of reflected light | |
| CN114660023A (en) | Refractive index measurement system and measurement based on total reflection common optical path polarization interference technology | |
| JP6196841B2 (en) | Transmitted wavefront measuring apparatus and transmitted wavefront measuring method | |
| KR20210157969A (en) | Imaging system and method for measuring fault of composite membrane | |
| JP5325481B2 (en) | Measuring method of optical element and manufacturing method of optical element | |
| CN116045841B (en) | Fitting method, fitting device and measuring system of focusing curve |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |