Transparent material detection method, system and correction method

Abstract

The invention discloses a transparent material detection method, a transparent material detection system and a transparent material correction method. The detection method comprises the following steps: matching a corresponding relationship between the number of wave crests in a spectrogram at each position on a scanning line and the number of wave crests corresponding to each defect type; identifying defect types with the same number of wave crests in the defect types; according to the identification method, the defect types with the same crest number are distinguished by judging whether the variable quantity of the measured height data corresponding to the second peak wavelength in the spectrogram at the adjacent position on the scanning line is within the allowable distance error range or not. According to the invention, the defect type at each position can be accurately identified, and the measured height data corresponding to each peak wavelength in the spectrogram at the position of the defect type can be compensated according to the defect type, so that the real measured height data of the surface and the interior of the transparent material can be obtained; the accuracy of surface and internal data detection of the transparent material is improved, and the quality of the transparent material can be accurately identified.

Description

Technical Field

[0001] The invention belongs to the technical field of spectral confocal technology and relates to a detection method, system and correction method of transparent materials. Background Art

[0002] The line spectrum confocal sensor is a high-precision, non-contact measurement technology that is widely used in industrial automation, precision engineering, scientific research and other fields. It can detect the thickness of transparent materials, which is directly related to the quality and performance of the product. For example, it can detect the thickness of mobile phone screens, film thickness, transparent silicone and other materials with high precision requirements.

[0003] When the line spectrum confocal sensor detects the thickness of a single layer of transparent material, there are cases where there are no less than two peaks in the spectrum at the detection position, and the thickness of the transparent material and the type of defects inside the transparent material cannot be accurately determined based on the peaks in the spectrum. Due to the influence of internal defects in the transparent material, the height data of the transparent material detection deviates from its true data, and cannot truly reflect the data information of the internal defects of the transparent material and the surface morphology data information. At the same time, it is impossible to make targeted corrections to the measured height data corresponding to different peak wavelengths according to different defect types, and it is impossible to accurately determine the coverage area corresponding to each defect type, which leads to inaccurate data detection inside and on the surface of the transparent material, seriously affecting the quality detection accuracy of transparent materials with high precision requirements.

[0004] Therefore, in order to solve the above problems, the present invention provides a transparent material detection method, system and correction method. Summary of the invention

[0005] The purpose of the present invention is to overcome the above problems existing in the prior art and to provide a detection method, system and correction method for transparent materials.

[0006] In order to achieve the above technical objectives and the above technical effects, the present invention is implemented through the following technical solutions: A method for detecting a transparent material, controlling a line spectrum confocal sensor to continuously scan the transparent material along a line scanning direction to obtain a spectrum diagram at each position on the scanning line, comprising: Match the corresponding relationship between the number of peaks in the spectrum at each position on the scan line and the number of peaks corresponding to each defect type, so as to preliminarily determine the defect type of the transparent material at each position; Identify defect types having the same number of peaks among the defect types; The method for identifying defect types with the same number of peaks in the defect types is to distinguish the defect types at each position with the number of peaks equal to the set number of peaks by judging whether the change in the measured height data corresponding to the second peak wavelength in the spectrum at adjacent positions on the scanning line is within the allowable distance error range; Among them, the defect types include bubbles inside the transparent material, non-transparent impurities and grooves at the bottom; The scanning line is a line formed by the position coordinates of the upper surface of the transparent material covered by the line light source; The peak wavelengths in the spectrum are numbered in order of light intensity. The relationship between the peak wavelengths at any position in the spectrum is as follows: as light is lost, the light intensity corresponding to each peak in the same spectrum decreases as the wavelength increases.

[0007] The method for identifying defect types having the same number of peaks in the defect type comprises analyzing the light intensity ratio of the first peak wavelength and the second peak wavelength in the spectrum graph at the same position on the scanning line; The relationship between the light intensity ratio and the set threshold range is determined to distinguish the defect type at each position where the number of peaks is equal to the set number of peaks.

[0008] The transparent material detection system includes: a defect recognition module, which extracts the number of peaks in the spectrum at each position on the scanning line and matches it with the number of peaks corresponding to each defect type to preliminarily determine the defect type of the transparent material at each position; The data analysis module determines whether the change in the measured height data corresponding to the second peak wavelength in the spectrum at adjacent positions on the scanning line is within the allowable distance error range, so as to distinguish the defect types at each position where the number of peaks is equal to the set number of peaks, wherein the scanning line is a line formed by the position coordinates of the upper surface of the transparent material covered by the line light source.

[0009] The data analysis module includes analyzing the light intensity ratio of the first peak wavelength and the second peak wavelength in the spectrum graph at the same position on the scan line; The relationship between the light intensity ratio and the set threshold range is determined to distinguish the defect type at each position where the number of peaks is equal to the set number of peaks.

[0010] Correction methods based on defect type, including: Extracting the focusing height data of light of different wavelengths after being dispersed by the dispersion lens group, so as to obtain the focusing height data of light of each wavelength along the optical axis in the propagation medium where the dispersion lens group is located; The training converges on the plane formed by the scanning line and the optical axis, and the standard incident angle of the peak wavelength at each position, so as to establish a mapping relationship between each wavelength and the standard incident angle, wherein the standard incident angle is the angle between the light and the normal perpendicular to the upper surface of the standard sample when light of different wavelengths is incident on the surface of the standard sample after passing through the dispersion lens group, and the optical axis of the line spectrum confocal sensor is perpendicular to the upper surface of the standard sample; The refractive index of the propagation medium through which the light of the peak wavelength passes during the convergence process, the incident angle of the wavelength, and the height data of the wavelength converged along the optical axis in the propagation medium where the dispersion lens group is located are analyzed to obtain the measured height compensation corresponding to the peak wavelength in the spectrum diagram at each position.

[0011] A computer-readable storage medium, a computer program, and the computer program implements the above correction method when executed by a processor.

[0012] The beneficial effects of the present invention are: (1) The present invention matches the number of peaks at each position with the number of peaks corresponding to each defect type to preliminarily determine the defect type of the transparent material, and further identifies the defect types with the same number of peaks in the defect type. The two-level defect type identification can accurately identify the defect type at each position, providing a basis for later correction of the measurement height of each peak wavelength according to different defect types.

[0013] (2) The present invention analyzes the light intensity ratio corresponding to the first peak wavelength and the second peak wavelength in the same spectrum to identify multiple defect types with the same number of peaks. In addition, by analyzing the change in the measured height data corresponding to two adjacent second peak wavelengths in the scanning line direction, multiple defect types with the same number of peaks can also be identified. This can reduce the inaccuracy of defect type identification based only on the number of peaks, thereby improving the accuracy of defect identification.

[0014] The present invention adaptively corrects the measured heights corresponding to different peak wavelengths at the same position under the identified defect type, and there are differences in the measured height corrections corresponding to the same peak wavelength under different defect types. Combined with the defect type and the order in which the peaks appear in the spectrum, the measured height data corresponding to each peak wavelength is compensated, and the real measured height data corresponding to each peak wavelength in the spectrum under each defect type is obtained, thereby reducing the error in height data detection, improving the accuracy of measurement height data detection corresponding to each peak wavelength, and eliminating the influence of the refractive index of transparent materials and internal defects on the measurement.

[0015] (4) The present invention compensates for the measured height data corresponding to the peak wavelength at the same position under each defect type in the transparent material, thereby eliminating the interference of different defects on the measured data. Through the compensated height data, not only the thickness of the transparent material can be obtained, but also the position of each defect type in the transparent material, the coverage area and the depth information of the defect type along the thickness direction of the transparent material can be obtained, thereby realizing the accurate identification of the defect size inside the transparent material, meeting the high-precision measurement requirements, providing reliable data for the quality detection of transparent materials, and improving the accuracy of the quality detection of transparent materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of this application. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings: Figure 1 is a flow chart of a detection method in the present invention; Figure 2 is a flow chart of another detection method in the present invention; Figure 3 It is a schematic diagram of the detection correction method in the present invention; Figure 4 It is a schematic diagram of bubble detection in the present invention; Figure 5 It is a schematic flow chart of the detection of the groove on the lower surface of the transparent material in the present invention; Figure 6 It is a schematic diagram of detecting the critical width of bubbles in the present invention; Figure 7 It is a detection schematic diagram of a width smaller than the critical width of a bubble in the present invention; Figure 8 It is a schematic diagram of detecting non-transparent impurities in the present invention; Fig. 9 It is a schematic diagram of detecting the critical width of non-transparent impurities in the present invention. DETAILED DESCRIPTION

[0017] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0018] The present application uses a line spectrum confocal sensor to detect transparent materials, which can obtain the surface morphology of the transparent material and facilitate the adjustment of defects inside the transparent material, thereby meeting the detection needs of the transparent material.

[0019] like Figure 1 As shown, this embodiment first provides a method for detecting transparent materials, controlling the line spectrum confocal sensor to continuously scan the transparent material along the line scanning direction to obtain a spectrum diagram at each position on the transparent material, including: Step 1: Match the number of peaks in the spectrum at each position on the scan line with the corresponding relationship between the number of peaks corresponding to each defect type, so as to preliminarily determine the defect type of the transparent material at each position; When the object to be measured is at a certain position within the measurement range of the line spectrum confocal sensor, only light of a specific wavelength is focused on the surface to be measured at that position. The light of the specific wavelength can be reflected from the surface of the object to be measured back to the fiber coupler and enter the spectrometer because it meets the confocal condition, while other wavelengths of light are in a defocused state on the surface of the object to be measured. The distribution of the reflected light at the light source is much larger than the size that the spectrometer can receive, so most of the light cannot enter the spectrometer. The distance value corresponding to the target is measured by the wavelength value at the maximum light intensity in the spectrum.

[0020] After the line light source in the line spectrum confocal sensor passes through the dispersion lens group, the light is dispersed and converged into the plane formed by the scanning line and the optical axis of the line spectrum confocal sensor. When the line spectrum confocal sensor scans the transparent material along the line scanning direction, a spectrum diagram at each position on the scanning line is obtained, and there are at least two peaks in the spectrum diagram at each position.

[0021] The transparent material may be glass, transparent silica gel, transparent resin material, transparent film, etc.

[0022] Extract the number of peaks in the spectrum at any position on the transparent material, and judge the type of defect based on the number of peaks in the spectrum at the coordinate position. In the same spectrum, the number of peaks is m, and the peak wavelengths are numbered in descending order according to the light intensity corresponding to each peak wavelength, namely the first peak wavelength, the second peak wavelength, and the mth peak wavelength.

[0023] When the plane formed by the scanning line of the line spectrum confocal sensor and the optical axis intersects with the bubble in the transparent material, four peaks appear in the spectrum graph at the position where the measuring line parallel to the optical axis and passing through the bubble intersects with the upper surface of the transparent material, and the wavelength light corresponding to the four peaks converges to the intersection of the measuring line and the upper surface of the glass, the intersection of the measuring line and the upper surface of the bubble, the intersection of the measuring line and the lower surface of the bubble, and the intersection of the measuring line and the lower surface of the glass, respectively. The measuring line is parallel to the optical axis and is located in the plane formed by the scanning line of the line spectrum confocal sensor and the optical axis, and light of different wavelengths converges to different heights on the measuring line.

[0024] When the plane formed by the scanning line of the line spectrum confocal sensor and the optical axis intersects the groove on the lower surface of the glass, three peaks appear in the spectrum graph at the position where the measuring line parallel to the optical axis and passing through the groove intersects with the upper surface of the transparent material. The wavelength light corresponding to the above three peaks converges to the intersection of the measuring line and the upper surface of the glass, the intersection of the measuring line and the groove on the lower surface of the glass, and the intersection of the measuring line and the surface of the stage supporting the glass.

[0025] When the plane formed by the scanning line of the line spectrum confocal sensor and the optical axis intersects with the non-transparent impurities in the transparent material, three peaks or two peaks appear in the spectrum diagram at the position where the measuring line parallel to the optical axis and perpendicular to the transparent material intersects with the upper surface of the transparent material. If there are three peaks, the wavelength light corresponding to the three peaks will converge to the intersection of the measuring line and the upper surface of the glass, the intersection of the measuring line and the non-transparent impurities, and the intersection of the measuring line and the lower surface of the glass; if there are two peaks, the wavelength light corresponding to the two peaks will converge to the intersection of the measuring line and the upper surface of the glass, and the intersection of the measuring line and the non-transparent impurities.

[0026] When the plane formed by the scanning line of the line spectrum confocal sensor and the optical axis intersects the bubbles in the glass and the grooves on the lower surface of the glass at the same time, five peaks appear in the spectrum graph at the position where the measuring line parallel to the optical axis and passing through the bubbles and the grooves intersects with the upper surface of the transparent material.

[0027] Step 2: identifying defect types with the same number of peaks among the defect types; Due to the influence of the defect type, the number of peaks in the spectrum at the same position may be the same, and the defect types with the same number of peaks cannot be further distinguished. For example, in the two cases where there are grooves on the lower surface of the glass and non-transparent impurities inside the glass, the number of peaks in the spectrum at the position where the measurement line of any of the above two defect types intersects with the upper surface of the glass is equal to 3.

[0028] The method for identifying defect types with the same number of peaks includes: Determine whether the change in the measured height data corresponding to the second peak wavelength in the spectrum at adjacent positions on the scan line is within the allowable distance error range, so as to distinguish the defect types at each position when the number of peaks is equal to the set number of peaks, where the set number of peaks is 3; Among them, the defect types include bubbles inside the transparent material, non-transparent impurities and grooves at the bottom; The scanning line is a line formed by the position coordinates of the upper surface of the transparent material covered by the line light source.

[0029] The transparent material detection system includes: a defect recognition module, which extracts the number of peaks in the spectrum at each position on the scanning line and matches it with the number of peaks corresponding to each defect type to preliminarily determine the defect type of the transparent material at each position; A data analysis module, which determines whether the variation of the measured height data corresponding to the second peak wavelength in the spectrum graph at adjacent positions on the scanning line is within the allowable distance error range, so as to distinguish the defect types at each position when the number of peaks is equal to the set number of peaks, wherein the scanning line is a line formed by the position coordinates of the upper surface of the transparent material covered by the line light source; The data processing module processes the refractive index of the propagation medium through which the light of each peak wavelength passes during the convergence process, the incident angle of the wavelength, and the height data of the wavelength converged along the optical axis in the propagation medium where the dispersion lens group is located, so as to obtain the measured height compensation corresponding to the peak wavelength in the spectrum diagram at each position.

[0030] Example 1

[0031] For defect types with the same number of peaks, it is difficult to accurately identify the defect type only by the number of peaks. When the number of peaks in the spectrum at each position in the transparent material is equal to the set number of peaks, the defect type of the glass is further identified, such as Figure 2 As shown, the following method is used: Step 1.1, extracting the light intensities I1 and I2 corresponding to the first peak wavelength and the second peak wavelength in the spectrum at the same position; Step 1.2, analyzing the light intensity ratio of the first peak wavelength and the second peak wavelength, wherein the light intensity ratio is equal to the ratio of the light intensity corresponding to the second peak wavelength to the light intensity corresponding to the first peak wavelength, and the light intensity ratio I2 / I1<1; Step 1.3, determine whether the light intensity ratio is within the set threshold range. If it is within the set threshold range, the defect type at the second peak wavelength convergence point is that there are non-transparent impurities inside the transparent material. If it is not within the set threshold range, the defect type at the second peak wavelength convergence point is that there are grooves on the lower surface of the transparent material. The above method can be used to further refine the defect types with the same number of peaks to identify the defect types.

[0032] The set threshold range is a numerical range interval formed by the ratio of the light intensity corresponding to the wavelength light converging to the surface of the non-transparent impurity to the light intensity corresponding to the first peak wavelength.

[0033] The non-transparent impurities hinder the refraction of light that converges to the surface of the non-transparent impurities, increasing the intensity of the reflected light. The grooves on the lower surface of the transparent material cause part of the light that converges to the grooves on the lower surface of the transparent material to be reflected and part to be refracted. Therefore, the light intensity ratio corresponding to the non-transparent impurities is greater than the light intensity ratio at the grooves on the lower surface of the transparent material.

[0034] Among them, the transparent material detection system includes: a defect recognition module, which extracts the number of peaks in the spectrum at each position on the scanning line and matches it with the number of peaks corresponding to each defect type to preliminarily determine the defect type of the transparent material at each position; The data analysis module analyzes the light intensity ratio of the first peak wavelength and the second peak wavelength in the spectrum diagram at the same position on the scanning line; determines the relationship between the light intensity ratio and the set threshold range to distinguish the defect type at each position when the number of peaks is equal to the set number of peaks.

[0035] The data processing module processes the refractive index of the propagation medium through which the light of each peak wavelength passes during the convergence process, the incident angle of the wavelength, and the height data of the wavelength converged along the optical axis in the propagation medium where the dispersion lens group is located, so as to obtain the measured height compensation amount corresponding to the peak wavelength in the spectrum diagram at each position.

[0036] Example 2

[0037] Compared with Example 1, when the number of peaks in the spectrum at each position in the transparent material is equal to the set number of peaks, the defect type at the position is identified. This embodiment adopts another identification method to further identify the defect type of the glass, using the following method: The number of wave peaks at each position on the scanning line is obtained, and the measured height data corresponding to the second peak wavelength is compensated to determine whether the change in the measured height data corresponding to two adjacent second peak wavelengths on the scanning line is within the allowable distance error range. If the change in the measured height data corresponding to two adjacent second peak wavelengths along the scanning line is within the allowable distance error range, it indicates that the detected glass defect type is a groove on the lower surface of the glass. If the change in the measured height data corresponding to two adjacent second peak wavelengths along the scanning line is greater than the allowable distance error range, it indicates that the detected glass defect type is non-transparent impurities inside the glass.

[0038] In the process of distinguishing defect types, if the plane formed by the scanning line and the optical axis intersects with the non-transparent impurities inside the transparent material, the measured height data corresponding to the second peak wavelength at each position on the scanning line will undergo a sudden jump change. If the defect type is a groove on the lower surface of the transparent material, the measured height data corresponding to the second peak wavelength at each position on the scanning line will change slowly and continuously.

[0039] Compensate the measured distance corresponding to the second peak wavelength in the spectrum to obtain the measured height deviation △X2 corresponding to the second peak wavelength: ;

[0040] The measured height data corresponding to the second peak wavelength after compensation: ;

[0041] in, It is expressed as the measured height data corresponding to the second peak wavelength in the propagation medium with a refractive index of n1 where the dispersion lens group is located; It is represented as the measured height data corresponding to the first peak wavelength in the propagation medium with a refractive index of n1 where the dispersion lens group is located, and the first peak wavelength converges to the upper surface of the glass; and All are measured height data corresponding to the peak wavelength without height compensation; n1 and n2 represent the refractive index of the propagation medium where the dispersion lens group is located and the refractive index of the glass, respectively; θ2 represents the standard incident angle of the wavelength λ2 converged to the upper surface of the glass bubble in the propagation medium with a refractive index of n1 where the dispersion lens group is located.

[0042] Example 3

[0043] like Figure 3 As shown, based on the defect type identified by the detection method of the transparent material, the defect type is corrected, and the correction method includes: Step S1, extracting the focusing height data of light of different wavelengths after being dispersed by the dispersion lens group, so as to obtain the measurement height data of light of each wavelength converging along the optical axis in the propagation medium where the dispersion lens group is located; By adjusting the distance between the dispersion lens group and the upper surface of the transparent material, light of different wavelengths can be converged to the upper surface of the transparent material, the first peak wavelength in the spectrum diagram is extracted, and the measurement height data of the convergence of light of different wavelengths along the optical axis in the propagation medium where the dispersion lens group is located is established.

[0044] The upper surface of a standard sample is selected to be perpendicular to the optical axis, and the standard sample is not limited to a transparent material or a non-transparent material. The lens in the line spectrum confocal sensor system is placed in a propagation medium, a dispersion lens group is provided in the lens, and the distance between the lens and the standard sample is adjusted. The first peak wavelength in the spectrum at the distance is selected, and the distance measured along the optical axis direction of each wavelength in the propagation medium is established by continuously adjusting the distance between the lens and the standard sample and the first peak wavelength in the spectrum at the distance.

[0045] Among them, the transparent material is selected from colorless transparent glass, and the propagation medium where the dispersion lens group is located can be selected from one of a gas environment and a liquid environment. The gas environment includes air or other gas environments with known refractive index, and the liquid environment includes water, oil, oil-water mixture and other transparent liquid environments, so that the light dispersed by the dispersion lens group can detect the thickness of the transparent material after passing through the propagation medium where the dispersion lens group is located.

[0046] Step S2, training the standard incident angle of the peak wavelength at each position in the plane formed by the scanning line and the optical axis, so as to establish a mapping relationship between each wavelength and the standard incident angle, wherein the standard incident angle is the angle between the light and the normal perpendicular to the upper surface of the standard sample when light of different wavelengths is incident on the surface of the standard sample after passing through the dispersion lens group, and the optical axis of the line spectrum confocal sensor is perpendicular to the upper surface of the standard sample; According to the relationship between the numerical aperture NA and the incident angle θ: NA=nsinθ, n is the refractive index in the propagation medium where the lens is located, and θ is the maximum incident angle between the light emitted from the optical axis and the optical axis. Since the numerical aperture of the lens is known, the maximum incident angle between the light emitted from the optical axis and the optical axis is obtained. This maximum incident angle is the wavelength incident angle corresponding to the minimum measurement height. By adjusting the distance between the lens and the surface of the standard sample and the numerical aperture NA, the incident angle corresponding to each wavelength in the propagation medium where the lens is located can be established.

[0047] If a standard sample is selected in which the optical axis of the lens is perpendicular to the upper surface of the standard sample, the incident angle of each wavelength obtained is the standard incident angle.

[0048] Step S3, analyzing the refractive index of the propagation medium through which the light of the peak wavelength passes during the convergence process, the incident angle of the wavelength, and the measured height data of the wavelength converging along the optical axis in the propagation medium where the dispersion lens group is located, so as to obtain the measured height compensation amount corresponding to the peak wavelength in the spectrum diagram at each position.

[0049] In the propagation medium where the dispersion lens group is located, the real measured height data corresponding to the peak wavelength in the spectrum at each position on the transparent material in the propagation medium where the dispersion lens group is located is obtained by summing the measured height compensation amount corresponding to the peak wavelength in the spectrum at each position and the height data converged along the optical axis direction in the propagation medium where the dispersion lens group is located.

[0050] The defect type at each position on the scanning line is identified, and the measured height data corresponding to the peak wavelength in the spectrum at each position on the scanning line is compensated to obtain the true measured height data corresponding to the other peak wavelengths except the first peak wavelength in the spectrum at each position on the scanning line.

[0051] Specifically, the compensation amounts of the measured height data corresponding to each peak wavelength at the same position are different. Affected by the defect type at the position and the order of the peak numbers at the position, the measured height data corresponding to the first peak wavelength in the spectrum graph does not need to be compensated. The measured height data corresponding to the first peak wavelength is the distance from the lens of the line spectrum confocal sensor to the upper surface of the transparent material. It is only necessary to compensate for the measured height data corresponding to other peak wavelengths in the spectrum graph to eliminate the situation where the measured height data corresponding to each peak wavelength after uncompensation is less than the actual measured height data due to the difference in the refractive index of the transparent material and the refractive index of the propagation medium where the dispersion lens group is located.

[0052] Affected by the height of the lens of the line spectrum confocal sensor from the upper surface of the glass, the thickness of the glass, the type of defects in the glass, and the height of the position of each defect type in the glass, it is impossible to determine the wavelength of the light that is dispersed by the dispersion lens group and converges to the upper surface of the glass, and it is also impossible to determine which specific wavelength converges to the glass surface, the upper surface of the bubble in the glass, the lower surface of the bubble in the glass, the bottom of the glass, etc., and thus it is impossible to compensate the measurement data corresponding to each wavelength in advance. The measurement height data of each peak wavelength converging in the air after passing through the dispersion lens group can be established according to the mapping relationship between different wavelengths and the measurement height data through each peak wavelength in the spectrum diagram, and the measurement height data corresponding to other peaks except the first peak can be compensated according to the number of peaks, so as to reduce the measurement height error caused by the change of refractive index in the process of light from air to glass, so as to accurately obtain the measurement height data corresponding to each peak.

[0053] Compensating the measured height data corresponding to the peak wavelength in the spectrum at each position on the scan line, wherein the compensation method for the measured height data corresponding to each peak wavelength in the spectrum at each position includes: Step W1, determine the defect type; When the number of peaks in the spectrum graph at each position on the scan line is the same, the defect type cannot be identified based solely on the number of peaks in the spectrum graph. The defect type determination method is to determine whether the number of peaks in the spectrum graph at each position on the scan line is equal to the set number of peaks. If it is equal to the set number of peaks, analyze whether the coefficient of the light intensity change of adjacent peaks in the spectrum graph at the position is within the allowable threshold error range to distinguish the defect type at each position when the number of peaks is equal to the set number of peaks, wherein the set number of peaks includes 3 peaks.

[0054] Step W2, extracting the height data of each peak wavelength in the spectrum at the position where it converges along the optical axis in the propagation medium where the dispersion lens group is located; Step W3, extracting interference factors that affect the real measured height data of the peak wavelength, wherein the interference factors include the standard incident angle of the peak wavelength and the refractive index of the propagation medium through which the light of the peak wavelength converges to the defect type; Step W4: Analyze the measurement height deviation corresponding to the peak wavelength to obtain the measurement height data corresponding to the compensated peak wavelength.

[0055] The compensation amount for the measured distance data corresponding to the second peak wavelength in the spectrum at each position is applicable to the compensation of the second peak wavelength when there is no defect inside the glass and to any defect type, wherein the arbitrary defect type includes bubbles inside the glass, grooves on the lower surface of the glass, and non-transparent impurities inside the glass.

[0056] Specifically, the measured distance data corresponding to the second peak wavelength in the spectrum is compensated to obtain the measured height deviation △X2 corresponding to the second peak wavelength: ;

[0057] The measured height data corresponding to the second peak wavelength after compensation: ;

[0058] in, It is expressed as the measured height data corresponding to the second peak wavelength in the propagation medium with a refractive index of n1 where the dispersion lens group is located; It is represented as the measured height data corresponding to the first peak wavelength in the propagation medium with a refractive index of n1 where the dispersion lens group is located, and the first peak wavelength converges to the upper surface of the glass; and All are measured height data corresponding to the peak wavelength without height compensation; n1 and n2 represent the refractive index of the propagation medium where the dispersion lens group is located and the refractive index of the glass, respectively; θ2 represents the standard incident angle of the wavelength λ2 converged to the upper surface of the glass bubble in the propagation medium with a refractive index of n1 where the dispersion lens group is located.

[0059] As the types of glass defects vary, the light rays converging to different positions on the glass change through the propagation medium, which affects the compensation amount of the measured height data corresponding to the third peak wavelength. It is necessary to determine the defect type based on the number of peaks at each position, and then select the compensation amount that matches the peak wavelength based on the defect type.

[0060] The light beam after passing through the dispersion lens group enters the transparent material with a large refractive index from the propagation medium with a small refractive index. The light emission and refraction make the convergence position of the light of the same wavelength in the propagation medium with a small refractive index be located directly above the transparent material with a large refractive index for the light of the same wavelength. Therefore, the measured height data of the light beam of each wavelength is affected by the propagation medium through which the light passes during the convergence process.

[0061] The third peak wavelength and other peak wavelengths are compensated in a targeted manner according to the defect type, specifically: like Figure 4 As shown, when there are bubbles in the glass, the number of peaks in the spectrum at the location of the bubbles is equal to 4, and the compensation amount of the measured height data corresponding to each peak wavelength on the spectrum is analyzed.

[0062] The wavelength light converged on the upper surface of the bubble corresponds to the second peak wavelength in the spectrum. The measured height data corresponding to the second peak wavelength is compensated. The compensation model of △X2 is used to obtain the measured height deviation △X2 corresponding to the second peak wavelength and the measured height data corresponding to the compensated second peak wavelength. .

[0063] When the measuring line passes through the bubble, the wavelength light converged to the lower surface of the bubble corresponds to the third peak wavelength in the spectrum, or when the measuring line passes through the groove on the lower surface of the glass, the wavelength light converged to the stage supporting the glass corresponds to the third peak wavelength in the spectrum. The measured height data corresponding to the third peak wavelength in the spectrum is compensated to obtain the measured height deviation △X3 corresponding to the third peak wavelength and the compensated measured height data : ;

[0064] The measured height data corresponding to the compensated third peak wavelength: ;

[0065] Wherein, L1 represents the distance between the intersection of the measuring line and the upper surface of the glass and the upper surface of the bubble, ; θ3 represents the standard incident angle of the wavelength λ3 converging to the lower surface of the glass bubble in the propagation medium with a refractive index of n1 where the dispersion lens group is located; It is expressed as the measured height data corresponding to the first peak wavelength in the propagation medium with a refractive index of n1 where the dispersion lens group is located; It is expressed as the measured height data corresponding to the third peak wavelength in the propagation medium with a refractive index of n1 where the dispersion lens group is located.

[0066] like Figure 5 As shown, the compensation amount of the measured height data corresponding to the third peak wavelength and the compensated measured height data are applicable to the measured height data corresponding to the third peak wavelength in the spectrum when there are grooves on the lower surface of the glass or bubbles inside the glass. When there are bubbles in the glass, the wavelength light converging to the lower surface of the bubbles corresponds to the third peak wavelength in the spectrum; when there is a groove on the lower surface of the glass, the wavelength light converging to the stage supporting the glass below the groove corresponds to the third peak wavelength in the spectrum.

[0067] The measured height data corresponding to the fourth peak wavelength in the spectrum diagram is also affected by the defect type, causing the propagation medium through which the converging light passes to change during the converging process. Therefore, adaptive compensation correction is performed on the fourth peak wavelength under different defect types.

[0068] Specifically: When the measuring line passes through the bubble, the wavelength light that converges to the lower surface of the glass corresponds to the fourth peak wavelength in the spectrum diagram. The measuring distance corresponding to the fourth peak wavelength is compensated to obtain the measuring height deviation △X4 corresponding to the fourth peak wavelength: ;

[0069] The measured height data corresponding to the compensated fourth peak wavelength: ;

[0070] Wherein, L1 represents the distance between the intersection of the measuring line and the upper surface of the glass and the upper surface of the bubble, ; L3 represents the distance between the intersection of the measuring line and the lower surface of the bubble and the lower surface of the glass; θ4 represents the standard incident angle of the wavelength λ4 converging to the lower surface of the glass bubble in the propagation medium with a refractive index of n1 where the dispersion lens group is located; It is expressed as the measured height data corresponding to the first peak wavelength in the propagation medium with a refractive index of n1 where the dispersion lens group is located; It is represented by the measured height data corresponding to the fourth peak wavelength in the propagation medium with a refractive index of n1 where the dispersion lens group is located; d is represented by the width of the bubble along the scanning line direction.

[0071] like Figure 8 As shown, when there are non-transparent impurities in the glass, when the non-transparent impurities are smaller than the length of the scanning line, three peaks and two peaks appear in the spectrum at each position in the scanning line direction. When three peak wavelengths appear, the measured height data corresponding to the third peak wavelength in the spectrum is compensated to obtain the measured height deviation △X3 corresponding to the third peak wavelength and the compensated measured height data : ; .

[0072] in, It is expressed as the measured height data corresponding to the first peak wavelength in the propagation medium with a refractive index of n1 where the dispersion lens group is located; It is represented by the measured height data corresponding to the third peak wavelength in the propagation medium with a refractive index of n1 where the dispersion lens group is located; θ3 is represented by the standard incident angle of the wavelength λ3 converged to the lower surface of the glass bubble in the propagation medium with a refractive index of n1 where the dispersion lens group is located.

[0073] Based on the coordinate data of each position on the scanning line and the measured height data corresponding to each peak wavelength in the spectrum diagram at each position after compensation, point cloud data in a three-dimensional coordinate system is constructed. The defect type, defect location and coverage area in the glass can be identified through the point cloud data to determine whether the glass quality meets the requirements.

[0074] The compensated data is converted into point cloud data in three-dimensional coordinates to construct glass morphology parameters and the type and coverage area of ​​internal defects in the glass. According to the type and coverage area of ​​defects, the glass quality is evaluated to determine whether the glass meets the requirements.

[0075] Example 4

[0076] According to the above-mentioned embodiment 3, the compensated measurement height data corresponding to each peak wavelength in the spectrum diagram at each position on each scanning line along the line scanning direction can be obtained to form point cloud data on the glass surface and in the thickness direction. Affected by the size of the bubbles, the compensation of the third peak wavelength at some positions in the scanning line direction deviates from the actual measurement height data, and the influence of the coverage area on the measurement accuracy needs to be considered.

[0077] When the bubble width d on the scan line is greater than the critical bubble width S, the measured height deviation corresponding to the third peak wavelength ; When the bubble width d on the scan line is less than or equal to the critical bubble width S, the measured height deviation corresponding to the third peak wavelength ; d represents the width of the bubble along the scanning line direction; in, ; When there is a bubble defect in the glass, the measured height data corresponding to the third peak wavelength is affected by the width of the bubble, L1 is represented by the distance between the intersection of the measuring line and the upper surface of the glass and the upper surface of the bubble; θ3 is represented by the standard incident angle of the wavelength λ3 converging to the lower surface of the glass bubble in the propagation medium with a refractive index of n1 where the dispersion lens group is located; It is expressed as the measured height data corresponding to the first peak wavelength in the propagation medium with a refractive index of n1 where the dispersion lens group is located; It is expressed as the measured height data corresponding to the third peak wavelength in the propagation medium with a refractive index of n1 where the dispersion lens group is located.

[0078] Example 5

[0079] In the process of determining the width and depth of the bubble, there is a situation where the light corresponding to the fourth peak wavelength does not pass through the bubble and directly converges to the lower surface of the glass, and there is a situation where the light of the fourth peak wavelength passes through the bubble and then converges to the lower surface. Therefore, when the light corresponding to the first peak wavelength does not pass through the bubble and directly converges to the lower surface of the glass, the measured height data corresponding to the compensated fourth peak wavelength is greater than the actual measured height data corresponding to the fourth peak wavelength.

[0080] Using the compensation amount of the fourth peak wavelength in Example 3 and the measured height data corresponding to the compensated fourth peak wavelength, the critical width W of the bubble that exists when the measured height data corresponding to the compensated fourth peak wavelength is greater than the actual measured height data corresponding to the fourth peak wavelength is analyzed, as shown in FIG. Figure 6 and 7 As shown: ;

[0081] in, ; ; θ4 represents the standard incident angle of wavelength λ4 converging to the lower surface of the glass bubble in the propagation medium with a refractive index of n1 where the dispersion lens group is located; △X3 is the measurement height deviation corresponding to the third peak wavelength converging to the lower surface of the bubble when the measurement line passes through the bubble.

[0082] When the bubble width on the scanning line is greater than the critical width W of the bubble, at W / 2 on the scanning line extending from the edge of the bubble to the center of the bubble, the light corresponding to the fourth peak wavelength does not pass through the bubble and directly converges to the lower surface of the glass, and the light of the fourth peak wavelength at other positions in the direction of the scanning line passes through the bubble and converges to the lower surface of the glass.

[0083] The bubble point cloud data obtained in Example 4 can be processed by the bubble width W to adjust the measured height data corresponding to the fourth peak wavelength in the spectrum at each position within the range of W / 2 extending from the bubble edge to the bubble center, and the adjustment is performed using the following formula: ; The measured height data corresponding to the compensated fourth peak wavelength: .

[0084] By adjusting the point cloud data corresponding to the fourth peak wavelength extending from the bubble edge to the bubble center at W / 2 in the scanning line direction, and taking the difference between the measured height data corresponding to the adjusted fourth peak wavelength and the compensated third peak wavelength, the bubble height data extending from the bubble edge to the bubble center at W / 2 in the scanning line direction can be obtained, thereby accurately obtaining the depth information of the bubbles in the transparent material.

[0085] Example 6

[0086] When the line spectrum confocal sensor detects non-transparent impurities inside the glass, affected by the width of the transparent impurities, the spectrum graph at the location of some non-transparent impurities along the scanning line direction may have three peaks or two peaks. Specifically, when there are non-transparent impurities in the glass blocking the incident light or reflected light converging to the bottom of the glass, there are only two peaks in the spectrum graph at this position; when the non-transparent impurities in the glass do not block the incident light and reflected light converging to the bottom of the glass, there are three peaks in the spectrum graph. When the light converging to the bottom of the glass is not blocked by the non-transparent impurities, the critical width value W0 of the non-transparent impurities is as follows: Fig. 9 As shown:

[0087] in, It is represented as the measured height data corresponding to the second peak wavelength in the propagation medium with a refractive index of n1 where the dispersion lens group is located; △X2 is represented as the measured height deviation corresponding to the second peak wavelength; It is expressed as the measured height data corresponding to the third peak wavelength in the propagation medium with a refractive index of n1 where the dispersion lens group is located; △X3 is the measured height deviation corresponding to the third peak wavelength that converges to the lower surface of the bubble when the measurement line passes through the bubble; θ3 is expressed as the standard incident angle of the wavelength λ3 that converges to the lower surface of the glass bubble in the propagation medium with a refractive index of n1 where the dispersion lens group is located.

[0088] Through the above-mentioned critical width value of the width of the non-transparent impurities that is not obstructed, combined with the line scanning distance L corresponding to the starting position coordinates and the end position coordinates of the non-transparent impurities in the scanning line direction, the actual width data W1=L-2×W0 of the non-transparent impurities in the glass is analyzed, avoiding taking the line scanning length under two consecutive peaks in the spectrum in the scanning line direction as the actual width of the non-transparent impurities, so that the measured width of the non-transparent impurities is greater than the actual width of the non-transparent impurities, thereby improving the accuracy of the width measurement of the non-transparent impurities.

[0089] Example 7

[0090] A fourth aspect of the present invention further provides a computer-readable storage medium, comprising a computer program, wherein the computer program implements the above-mentioned detection method when executed by a processor.

[0091] In practical applications, the computer-readable storage medium may adopt any combination of one or more computer-readable media. The computer-readable medium may be a computer-readable signal medium or a computer-readable storage medium. The computer-readable storage medium may be, but is not limited to, an electrical, magnetic, optical, electromagnetic, infrared or semiconductor system, device or device, or any combination of the above. More specific examples of computer-readable storage media may include: an electrical connection with one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above. In this embodiment, the computer-readable storage medium may be any tangible medium containing or storing a program, which may be used by or in combination with an instruction execution system, device or device.

[0092] Computer-readable signal media may include data signals propagated in baseband or as part of a carrier wave, which carry computer-readable program code. Such propagated data signals may take a variety of forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination of the above. Computer-readable signal media may also be any computer-readable medium other than a computer-readable storage medium, which may send, propagate, or transmit a program for use by or in conjunction with an instruction execution system, apparatus, or device.

[0093] The program code embodied on the computer readable medium may be transmitted using any appropriate medium, including but not limited to wireless, wireline, optical fiber cable, RF, etc., or any suitable combination of the foregoing.

[0094] Computer program code for performing the operation of the present application may be written in one or more programming languages ​​or a combination thereof, including object-oriented programming languages, such as Java, Smalltalk, C++, and conventional procedural programming languages, such as "C" or similar programming languages. The program code may be executed entirely on the user's computer, partially on the user's computer, as a separate software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In the case of a remote computer, the remote computer may be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computer (e.g., via the Internet using an Internet service provider).

[0095] In the description of this specification, the description with reference to the terms "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0096] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments, and the above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, and these changes and improvements all fall within the scope of the present invention to be protected.

Claims

1. A method for detecting transparent materials, controlling a line spectrum confocal sensor to continuously scan the transparent material along a line scanning direction to obtain a spectrum diagram at each position on the scanning line, characterized in that: include: Match the corresponding relationship between the number of peaks in the spectrum at each position on the scan line and the number of peaks corresponding to each defect type, so as to preliminarily determine the defect type of the transparent material at each position; Identify defect types having the same number of peaks among the defect types; The method for identifying defect types with the same number of peaks in the defect types is to distinguish the defect types at each position with the number of peaks equal to the set number of peaks by judging whether the change in the measured height data corresponding to the second peak wavelength in the spectrum at adjacent positions on the scanning line is within the allowable distance error range; Among them, the defect types include bubbles inside the transparent material, non-transparent impurities and grooves at the bottom; The scanning line is a line formed by the position coordinates of the upper surface of the transparent material covered by the line light source; In the spectrum diagram, each peak wavelength is numbered in order of light intensity.

2. The method for detecting transparent materials according to claim 1, characterized in that: A method for identifying defect types with the same number of peaks in the defect types, including analyzing the light intensity ratio of the first peak wavelength and the second peak wavelength in the spectrum graph at the same position on the scan line; The relationship between the light intensity ratio and the set threshold range is determined to distinguish the defect type at each position where the number of peaks is equal to the set number of peaks.

3. A method for correcting a transparent material, characterized in that: The correction method is based on the defect type identified by the transparent material detection method according to claim 1 or 2, and includes: Extracting the focusing height data of light of different wavelengths after being dispersed by the dispersion lens group, so as to obtain the focusing height data of light of each wavelength along the optical axis in the propagation medium where the dispersion lens group is located; Training the standard incident angle of the peak wavelength at each position in the plane formed by the scanning line and the optical axis, so as to establish a mapping relationship between each wavelength and the standard incident angle, wherein the standard incident angle is the angle between the light and the normal perpendicular to the upper surface of the standard sample when light of different wavelengths is incident on the surface of the standard sample after passing through the dispersion lens group, and the optical axis of the line spectrum confocal sensor is perpendicular to the upper surface of the standard sample; The refractive index of the propagation medium through which the light of the peak wavelength passes during the convergence process, the incident angle of the wavelength, and the height data of the wavelength converged along the optical axis in the propagation medium where the dispersion lens group is located are analyzed to obtain the measured height compensation corresponding to the peak wavelength in the spectrum diagram at each position.

4. The correction method according to claim 3, characterized in that: The defect type at each position on the scanning line is identified, and the measured height corresponding to the peak wavelength in the spectrum at each position on the scanning line is compensated to obtain the real measured height data corresponding to the other peak wavelengths except the first peak wavelength in the spectrum at each position on the scanning line.

5. The correction method according to claim 4, characterized in that: Compensating the measured height corresponding to the peak wavelength in the spectrum at each position on the scan line, wherein the compensation method for the measured height corresponding to each peak wavelength in the spectrum at each position includes: Determine the defect type; Extracting the height data of each peak wavelength in the spectrum at the position where it converges along the optical axis in the propagation medium where the dispersion lens group is located; Extracting interference factors that affect the real measured height data of the peak wavelength, wherein the interference factors include a standard incident angle of the peak wavelength and a refractive index of a propagation medium through which light of the peak wavelength converges to a defect type; The measured height deviation corresponding to the peak wavelength is analyzed to obtain the measured height data corresponding to the compensated peak wavelength.

6. The correction method according to claim 5, characterized in that: When the defect type is non-transparent impurities, the method for correcting the defect coverage length on the scanning line includes: Extracting compensated measured height data corresponding to the second peak wavelength and the third peak wavelength at the same position in the scanning line direction and the incident angle of the third peak wavelength in the propagation medium where the dispersion lens group is located; Analyzing the critical width data of the non-transparent impurities at the position to determine the deviation of the coverage length of the non-transparent impurities in the scanning line direction; The coverage length of the corrected non-transparent impurities on the scan line is calculated to obtain the actual coverage length of the non-transparent impurities.

7. A transparent material detection system, characterized in that: include: The defect recognition module extracts the number of peaks in the spectrum at each position on the scan line and matches it with the number of peaks corresponding to each defect type to preliminarily determine the defect type of the transparent material at each position; The data analysis module determines whether the change in the measured height data corresponding to the second peak wavelength in the spectrum at adjacent positions on the scanning line is within the allowable distance error range, so as to distinguish the defect types at each position where the number of peaks is equal to the set number of peaks, wherein the scanning line is a line formed by the position coordinates of the upper surface of the transparent material covered by the line light source.

8. The transparent material detection system according to claim 7, characterized in that: The data analysis module includes analyzing the light intensity ratio of the first peak wavelength and the second peak wavelength in the spectrum graph at the same position on the scan line; The relationship between the light intensity ratio and the set threshold range is determined to distinguish the defect type at each position where the number of peaks is equal to the set number of peaks.

9. The transparent material detection system according to claim 7 or 8, characterized in that: Also included is a data processing module for correcting the measured height data corresponding to the peak wavelength at the location of the defect type in the transparent material; The data processing module processes the refractive index of the propagation medium through which the light of each peak wavelength passes during the convergence process, the incident angle of the wavelength, and the height data of the wavelength converged along the optical axis in the propagation medium where the dispersion lens group is located, so as to obtain the measured height compensation amount corresponding to the peak wavelength in the spectrum diagram at each position.

10. A computer-readable storage medium comprising a computer program, characterized in that: When the computer program is executed by a processor, the correction method according to any one of claims 3 to 6 is implemented.

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