Glass thickness measuring method and system

Abstract

The invention relates to a glass thickness measuring method and system. The method comprises the following steps: enabling detection laser to penetrate through a loading clamp and directly enter a detection probe, acquiring first light intensity data at a plurality of wavelength sampling points through a high-frequency power meter, and constructing an initial light information matrix; a to-be-detected sample is placed on the carrying clamp, the detection laser is made to transmit the to-be-detected sample and then enter the detection probe, second light intensity data at the multiple wavelength sampling points are obtained through the high-frequency power meter, and a target light information matrix is constructed. A target power loss matrix is determined based on the target optical information matrix and the initial optical information matrix. And obtaining a plurality of transmission peaks and peak frequencies corresponding to the transmission peaks based on the target power loss matrix to obtain a transmission peak matrix. A peak frequency spacing average is determined based on the transmission peak matrix. And determining thickness data of the to-be-measured sample according to the average value of the peak frequency spacing and the refractive index and the light velocity of the to-be-measured sample. According to the invention, high-precision and high-efficiency non-contact thickness measurement can be realized.

Description

Technical Field

[0001] This application relates to the field of optical inspection technology, and in particular to a method and system for measuring glass thickness. Background Technology

[0002] Ultra-precision flat glass is a special type of glass with extremely high surface accuracy and nanoscale surface roughness, commonly used in optics, semiconductors, and cutting-edge technology fields. Thickness measurement is one of the important steps in the manufacturing process of ultra-precision flat glass. Non-contact measurement methods for the thickness of ultra-precision flat glass mainly include laser triangulation, spectral confocal method, and white light interferometry.

[0003] Among these methods, the laser triangulation method falls short of the nanometer-level accuracy requirements for ultra-precision planar glass in the current optical industry; the spectral confocal method has high requirements for the thickness of the structure under test and is generally only applicable to thin film or sheet glass, and the development of the spectral wavelength-thickness alignment algorithm for the spectral confocal method is quite difficult; the white light interferometry method has a difficult system setup and generally low detection efficiency. All of these methods are insufficient for achieving high-precision and high-efficiency non-contact thickness measurement of ultra-precision planar glass. Summary of the Invention

[0004] Based on this, the embodiments of this application provide a glass thickness measurement method and system, which can realize non-contact thickness measurement of the sample to be measured, and can effectively improve the measurement accuracy and measurement efficiency of non-contact thickness measurement.

[0005] To achieve the above objectives, some embodiments of this application provide a method for measuring glass thickness. This method includes the following steps.

[0006] The first light output port of the laser emitting device and the detection probe of the high-frequency power meter are placed on both sides of the loading fixture.

[0007] When the sample is not supported on the fixture, a detection laser is emitted through the first light outlet so that the detection laser passes through the fixture and directly enters the detection probe. The first light intensity data at multiple wavelength sampling points is obtained through the high-frequency power meter to construct an initial optical information matrix.

[0008] The sample to be tested is placed on the carrier fixture, and the detection laser is transmitted through the target position of the sample to be tested and then incident on the detection probe. The second light intensity data at multiple wavelength sampling points is obtained by the high-frequency power meter to construct the target light information matrix.

[0009] Based on the target optical information matrix and the initial optical information matrix, the target power loss matrix is ​​determined.

[0010] Based on the target power loss matrix, a peak-finding algorithm is used to identify and obtain multiple transmission peaks and the peak frequency corresponding to each transmission peak, so as to obtain the transmission peak matrix.

[0011] Based on the transmission peak matrix, the average value of the peak frequency spacing is determined.

[0012] The thickness data of the sample at the target location is determined based on the average value of the peak frequency spacing, the refractive index of the sample under test, and the speed of light.

[0013] In some embodiments, determining the target power loss matrix based on the target optical information matrix and the initial optical information matrix includes the following steps.

[0014] Based on the first light intensity data and the second light intensity data, a first power loss matrix in the wavelength domain is determined.

[0015] The first power loss matrix is ​​transformed from the wavelength domain to the frequency domain to determine the second power loss matrix in the frequency domain.

[0016] The second power loss matrix is ​​smoothed using a smoothing algorithm to determine the target power loss matrix.

[0017] In some embodiments, determining the average value of the transmission peak frequency spacing based on the transmission peak matrix includes the following steps.

[0018] Based on the transmission peak matrix and attenuation coefficient, an interpolation algorithm is used to determine the right attenuation point frequency and the left attenuation point frequency corresponding to each transmission peak in the transmission peak matrix.

[0019] Based on the attenuation point frequency on the right and the attenuation point frequency on the left, the corrected peak frequency corresponding to each transmission peak is determined.

[0020] The average value of the peak frequency spacing is calculated based on the corrected peak frequency and the number of transmission peaks.

[0021] In some embodiments, the first light-emitting port includes a collimator, and the laser emitting device further includes a collimator fine-tuning mechanism connected to the collimator; the bottom of the loading fixture is provided with a fixture fine-tuning mechanism. After placing the first light-emitting port of the laser emitting device and the detection probe of the high-frequency power meter on both sides of the loading fixture, and before acquiring the first light intensity data at multiple wavelength sampling points through the high-frequency power meter to construct an initial optical information matrix, the glass thickness measurement method further includes the following steps.

[0022] When the sample is not supported on the fixture, the detection laser is emitted through the collimator, and the collimator fine-tuning mechanism is adjusted so that the emission direction of the detection laser is perpendicular to the photosensitive surface of the detection probe.

[0023] The calibration sample is placed on the carrier fixture, and the detection laser is transmitted through the calibration sample and then incident on the detection probe. The fixture fine-tuning mechanism is adjusted so that the target surface of the calibration sample is perpendicular to the emission direction of the detection laser.

[0024] Remove the calibration sample.

[0025] In some embodiments, the loading fixture is disposed on a mobile platform; the number of samples to be tested is multiple. The glass thickness measurement method further includes the following steps.

[0026] Multiple samples to be tested are laid flat on the loading fixture.

[0027] The moving platform is translated so that the detection laser sequentially transmits through each of the test samples, and the target light information matrix corresponding to each test sample is constructed respectively.

[0028] Based on the target light information matrix corresponding to each of the test samples, the thickness data of each test sample is measured.

[0029] In some embodiments, the loading fixture is disposed on a mobile platform. The glass thickness measurement method further includes the following steps.

[0030] The sample to be tested is placed on the loading fixture.

[0031] The moving platform is translated so that the detection laser sequentially transmits through multiple detection positions on the sample to be tested, and the target light information matrix corresponding to each detection position is constructed respectively.

[0032] Based on the target light information matrix corresponding to each detection position, the thickness data of each detection position is measured.

[0033] The thickness of the sample to be tested is determined based on the average of the thickness data from multiple detection locations.

[0034] On the other hand, this application also provides a glass thickness measurement system according to some embodiments; the glass thickness measurement system can be used to perform the glass thickness measurement methods in the above embodiments.

[0035] In some embodiments, the glass thickness measurement system includes a laser emitting device, a sample holder, a high-frequency power meter, a matrix construction module, a data processing module, and a calculation module. The laser emitting device includes a light source and a first light-emitting port; the light source provides a detection laser; the first light-emitting port is connected to the light source and emits the detection laser; the sample holder carries the sample to be tested; the high-frequency power meter includes a detection probe, with the first light-emitting port and the detection probe located on opposite sides of the sample holder; the high-frequency power meter is configured to: when the sample holder is not carrying a sample, sample the detection laser passing through the sample holder and directly incident on the detection probe to obtain first light intensity data at multiple wavelength sampling points; after the sample to be tested is placed on the sample holder, sample the detection laser that has penetrated the target position of the sample and is incident on the detection probe to obtain second light intensity data at multiple wavelength sampling points; the matrix construction module is connected to the high-frequency power meter. The connection is configured to: construct an initial optical information matrix based on the multiple wavelength sampling points and the first light intensity data; construct a target optical information matrix based on the multiple wavelength sampling points and the second light intensity data; the data processing module is connected to the matrix construction module and is configured to: determine a target power loss matrix based on the target optical information matrix and the initial optical information matrix; the calculation module is connected to the data processing module and is configured to: identify and obtain multiple transmission peaks and the peak frequencies corresponding to each transmission peak using a peak-finding algorithm based on the target power loss matrix to obtain a transmission peak matrix; determine the average value of the peak frequency spacing based on the transmission peak matrix; and determine the thickness data of the sample under test at the target position based on the average value of the peak frequency spacing, the refractive index of the sample under test, and the speed of light.

[0036] In some embodiments, the data processing module includes a first determining unit, a matrix transformation unit, and a smoothing processing unit. The first determining unit is configured to: determine a first power loss matrix in the wavelength domain based on the first light intensity data and the second light intensity data; the matrix transformation unit is connected to the first determining unit and is configured to: transform the first power loss matrix from the wavelength domain to the frequency domain to determine a second power loss matrix in the frequency domain; the smoothing processing unit is connected to the matrix transformation unit and is configured to: perform data smoothing processing on the second power loss matrix using a smoothing shift algorithm to determine a target power loss matrix.

[0037] In some embodiments, the calculation module includes a second determining unit, a third determining unit, and a first calculation unit. The second determining unit is configured to: determine the right-side attenuation point frequency and the left-side attenuation point frequency corresponding to each transmission peak in the transmission peak matrix using an interpolation algorithm based on the transmission peak matrix and the attenuation coefficient; the third determining unit is connected to the second determining unit and is configured to: determine the corrected peak frequency corresponding to each transmission peak based on the right-side attenuation point frequency and the left-side attenuation point frequency; the first calculation unit is connected to the third determining unit and is configured to: calculate the average value of the peak frequency spacing based on the corrected peak frequency and the number of transmission peaks.

[0038] In some embodiments, the first light outlet includes a collimator; the laser emitting device further includes a collimator fine-tuning mechanism connected to the collimator; the glass thickness measurement system further includes a fixture fine-tuning mechanism and an optical path calibration module. The fixture fine-tuning mechanism is located at the bottom of the loading fixture and is used to adjust the tilt angle of the loading fixture; the optical path calibration module is connected to the collimator fine-tuning mechanism and the fixture fine-tuning mechanism, and is configured to: adjust the collimator fine-tuning mechanism so that the emission direction of the detection laser is perpendicular to the photosensitive surface of the detection probe when the loading fixture is not carrying a sample; and adjust the fixture fine-tuning mechanism so that the target surface of the calibration sample is perpendicular to the emission direction of the detection laser when a calibration sample is placed on the loading fixture.

[0039] The embodiments of this application may have, or at least have, the following advantages:

[0040] In this embodiment, a detection laser is emitted from a laser emitting device and then incident on the detection probe of a high-frequency power meter after passing through the target position of the sample under test. This achieves non-contact measurement of the thickness data at the target position of the sample under test, without damaging the surface finish of the sample, thus improving product yield. Furthermore, this application can acquire light intensity data and construct an initial and target optical information matrix using a high-frequency power meter based on a simple optical path without the need for a spectrometer. The thickness measurement range is not limited by the capabilities of the dispersive lens and spectrometer, effectively increasing both the measurable thickness range and measurement accuracy. In addition, this application determines the target power loss matrix based on the initial and target optical information matrices and identifies the transmission peak matrix to determine the average peak frequency spacing. Then, based on the average peak frequency spacing, the refractive index of the sample under test, and the speed of light, the thickness data of the sample under test at the target position is directly calculated. The test system setup and calculation method are relatively simple, requiring no high-precision scanning or complex phase-shifting algorithms, thereby improving measurement efficiency. With the combined effect of the above technical features, this application can realize non-contact thickness measurement of the sample to be tested, and can effectively improve the measurement accuracy and measurement efficiency of non-contact thickness measurement.

[0041] Details of one or more embodiments of this application are set forth in the following drawings and description. Other features, objects, and advantages of this application will become apparent from the specification, drawings, and claims. Attached Figure Description

[0042] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0043] Figure 1 This is a flowchart illustrating a glass thickness measurement method provided in some embodiments;

[0044] Figure 2 This is a flowchart illustrating another glass thickness measurement method provided in some embodiments;

[0045] Figure 3 This is a flowchart illustrating step S400 provided in some embodiments;

[0046] Figure 4 This is a frequency amplitude diagram composed of power loss and frequency, provided in some embodiments;

[0047] Figure 5This is a flowchart illustrating step S600 provided in some embodiments;

[0048] Figure 6 This is a flowchart illustrating yet another glass thickness measurement method provided in some embodiments;

[0049] Figure 7 This is a flowchart illustrating yet another glass thickness measurement method provided in some embodiments;

[0050] Figure 8 This is a schematic diagram of the structure of a glass thickness measurement system provided in some embodiments;

[0051] Figure 9 This is a schematic diagram of another glass thickness measurement system provided in some embodiments;

[0052] Figure 10 This is a schematic diagram of another glass thickness measurement system provided in some embodiments;

[0053] Figure 11 This is a schematic diagram of another glass thickness measurement system provided in some embodiments.

[0054] Explanation of reference numerals in the attached figures:

[0055] S-Sample to be tested, 11-Light source, 12-First light outlet, 13-Collimator fine-tuning mechanism, 14-Circulator, 15-Second light outlet, 21-Plagging fixture, 22-Fixture fine-tuning mechanism, 23-Moving platform, 3-High-frequency power meter, 31-Detection probe, 32-Calibration probe, 4-Matrix construction module, 5-Data processing module, 51-First determination unit, 52-Matrix transformation unit, 53-Smoothing processing unit, 6-Calculation module, 61-Second determination unit, 62-Third determination unit, 63-First calculation unit, 7-Optical path calibration module. Detailed Implementation

[0056] To facilitate understanding of this application, a more complete description will be provided below with reference to the accompanying drawings, which illustrate preferred embodiments of the application. However, this application may be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that the disclosure of this application will be thorough and complete.

[0057] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

[0058] It should be understood that when an element or layer is referred to as being "on," "adjacent to," or "connected to" other elements or layers, it may be directly on, adjacent to, connected to, or coupled to other elements or layers, or there may be intervening elements or layers. It should be understood that although the terms first, second, third, etc., may be used to describe various elements, components, regions, layers, doping types, and / or portions, these elements, components, regions, layers, doping types, and / or portions should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer, doping type, or portion from another element, component, region, layer, doping type, or portion. Therefore, without departing from the teachings of this application, the first element, component, region, layer, doping type, or portion discussed below may be referred to as a second element, component, region, layer, or portion.

[0059] When used herein, the singular forms of “a,” “an,” and “the” may also include the plural forms unless the context clearly indicates otherwise. It should also be understood that when the terms “comprise” and / or “comprising” are used in this specification, the presence of the stated feature, integer, step, operation, element, and / or part is established, but the presence or addition of one or more other features, integers, steps, operations, elements, parts, and / or groups is not excluded. Meanwhile, when used herein, the term “and / or” includes any and all combinations of the associated listed items.

[0060] Embodiments of the invention are described herein with reference to cross-sectional views illustrating preferred embodiments (and intermediate structures) of this application, thus allowing for the anticipation of variations in the illustrated shapes due to, for example, manufacturing techniques and / or tolerances. Embodiments of this application should not be limited to the specific shapes of the regions shown herein, but rather include shape deviations due to, for example, manufacturing techniques. Therefore, the regions shown in the figures are substantially schematic, and their shapes do not represent the actual shapes of regions of the device, nor do they limit the scope of this application.

[0061] This application provides a glass thickness measurement method and system that can achieve non-contact thickness measurement of the sample under test, and can effectively improve the measurement accuracy and efficiency of non-contact thickness measurement.

[0062] In some embodiments, please refer to Figure 1 The glass thickness measurement method includes the following steps S100~S700.

[0063] S100, place the first light output port of the laser emitting device and the detection probe of the high-frequency power meter on both sides of the loading fixture.

[0064] In some embodiments, the first light outlet includes a collimator, and the laser emitting device further includes a collimator fine-tuning mechanism connected to the collimator; the bottom of the loading fixture is provided with a fixture fine-tuning mechanism.

[0065] For example, the laser emitting device also includes a light source and a circulator. The light source is used to provide the detection laser; the circulator connects the light source and the collimator and is used to transmit the detection laser emitted by the light source unidirectionally to the collimator.

[0066] For example, a collimator is used to convert a diverging laser beam provided by a light source into a parallel laser beam.

[0067] For example, the light source can be a continuous scanning laser source; the detection laser can be a high-resolution wavelength laser.

[0068] In the above embodiments, please refer to Figure 2 After step S100 and before step S200, the glass thickness measurement method further includes the following steps S110 to S130.

[0069] S110, when the sample is not supported on the fixture, emits a detection laser through a collimator and adjusts the collimator fine-tuning mechanism to make the emission direction of the detection laser perpendicular to the photosensitive surface of the detection probe.

[0070] S120: Place the calibration sample on the carrier fixture, so that the detection laser passes through the calibration sample and then enters the detection probe, and adjust the fixture fine-tuning mechanism so that the target surface of the calibration sample is perpendicular to the emission direction of the detection laser.

[0071] S130, remove the calibration sample.

[0072] In some examples, the glass thickness measurement method further includes the following step S201 before step S200.

[0073] S201, Set the light source scanning parameters.

[0074] For example, the light source scanning parameters include the starting wavelength. End wavelength And the scanning step size s.

[0075] S200, when the sample is not supported on the fixture, emits a detection laser through the first light outlet so that the detection laser passes through the fixture and directly enters the detection probe. The first light intensity data at multiple wavelength sampling points is obtained by a high-frequency power meter to construct an initial optical information matrix.

[0076] For example, multiple wavelength sampling points are based on the starting wavelength. Starting with and ending with wavelength The system takes multiple wavelength values ​​at intervals of s, with the endpoint as the scanning step. The first light intensity data consists of multiple light intensity values ​​corresponding to the multiple wavelength sampling points.

[0077] For example, the initial light information matrix It is a matrix of shape (2, k):

[0078] ;in, ;

[0079] in, This is the first light intensity data. The starting wavelength, The wavelength is the end wavelength, and s is the scan step size. For multiple wavelength sampling points.

[0080] The S300 places the sample to be tested on the carrier fixture, and then the detection laser passes through the target position of the sample and enters the detection probe. The second light intensity data at multiple wavelength sampling points are obtained by a high-frequency power meter to construct the target light information matrix.

[0081] For example, the material of the sample to be tested may include light-transmitting materials, such as glass.

[0082] For example, the sample to be tested includes, but is not limited to, flat glass.

[0083] For example, the target light information matrix It is a matrix of shape (2, k):

[0084] ;in, ;

[0085] in, This is the second light intensity data. The starting wavelength, The wavelength is the end wavelength, and s is the scan step size. For multiple wavelength sampling points.

[0086] S400 determines the target power loss matrix based on the target optical information matrix and the initial optical information matrix.

[0087] In some embodiments, please refer to Figure 3 Step S400 includes the following steps S410~S430.

[0088] S410, based on the first light intensity data and the second light intensity data, determine the first power loss matrix in the wavelength domain.

[0089] For example, step S410 includes: transferring the target light information matrix The power component and the initial optical information matrix in The power components in the matrix are subtracted; for example, the power loss data in the first power loss matrix can be determined by subtracting the corresponding positions of each second light intensity data from the first light intensity data in the matrix.

[0090] For example, the first power loss matrix It is a matrix of shape (2, k):

[0091] ;in, ; , ..., ;

[0092] in, For power loss data, This is the first light intensity data. This is the second light intensity data. The starting wavelength, The wavelength is the end wavelength, and s is the scan step size.

[0093] S420, transform the first power loss matrix from the wavelength domain to the frequency domain to determine the second power loss matrix in the frequency domain.

[0094] For example, in step S420, the wavelength in the first power loss matrix is ​​converted to frequency to realize the transformation of the first power loss matrix from the wavelength domain to the frequency domain; this can be calculated according to the following formula:

[0095] ;

[0096] Where f is the frequency and c is the speed of light. λ is the wavelength.

[0097] For example, the second power loss matrix It is a matrix of shape (2, k):

[0098] ;in, ; , ..., ; , ..., ;

[0099] in, For power loss data, This is the first light intensity data. This is the second light intensity data. The starting wavelength, The wavelength is the end wavelength, s is the scan step size, and c is the speed of light. The starting frequency, This is the end frequency.

[0100] S430 uses a smoothing algorithm to smooth the data of the second power loss matrix and determines the target power loss matrix.

[0101] It should be noted that due to the varying thickness of the flat glass at different locations, the optical path difference of the detection laser after reflections within the glass differs, resulting in multi-beam interference. According to the principle of multi-beam interference, at a certain wavelength, if the phase difference of the detection laser beam reaching the probe is an integer multiple of 2π, constructive interference will occur, forming a transmission peak; at another wavelength, if the phase difference is an odd multiple of π, destructive interference will occur, suppressing the light intensity. For further details, please refer to [link to relevant documentation]. Figure 4 Second power loss matrix Initial power loss data The test frequency f can form a frequency amplitude diagram with high and low fluctuations.

[0102] For example, in step S430, the second power loss matrix can be calculated according to the following formula. Perform data smoothing to determine the target power loss data. :

[0103] ;in, ;

[0104] in, It is the second power loss matrix The j-th light intensity data point in the data. It is the light intensity value after smoothing.

[0105] It should be noted that step S430 includes: using target power loss data Replace the second power loss matrix Initial power loss data To obtain the target power loss matrix.

[0106] In this embodiment of the application, by performing data smoothing processing, noise in the data acquisition process can be filtered out, thereby further improving the accuracy of thickness measurement.

[0107] S500 uses a peak-finding algorithm to identify and obtain multiple transmission peaks and their corresponding peak frequencies based on the target power loss matrix, in order to obtain the transmission peak matrix.

[0108] For example, in step S500, multiple transmission peaks of the target power loss matrix can be obtained according to the following formula:

[0109] ;in, ;

[0110] in, is the smoothed light intensity value, w is the window size, and T is the preset threshold.

[0111] For example, the transmission peak matrix is ​​a matrix of shape (2, m):

[0112] ;

[0113] Where m is the number of transmission peaks. … There are multiple transmission peaks. … It is the peak frequency corresponding to multiple transmission peaks.

[0114] S600 determines the average value of the peak frequency spacing based on the transmission peak matrix.

[0115] In some embodiments, please refer to Figure 5 Step S600 includes the following steps S610~S630.

[0116] S610, based on the transmission peak matrix and attenuation coefficient, uses an interpolation algorithm to determine the right attenuation point frequency and left attenuation point frequency corresponding to each transmission peak in the transmission peak matrix.

[0117] For example, step S610 includes: finding two consecutive data points to the right of each transmission peak. and And it satisfies the mathematical expression: Where d is the attenuation coefficient. Based on this, the frequency of the attenuation point on the right is calculated and determined using an interpolation algorithm. :

[0118] ;

[0119] in, It is a transmission peak.

[0120] Similarly, in step S610, the frequency of the left attenuation point is also calculated and determined. .

[0121] S620 determines the corrected peak frequency corresponding to each transmission peak based on the attenuation point frequency on the right and the attenuation point frequency on the left.

[0122] In some examples, step S620 may use methods such as calculating the average value or Gaussian fitting to determine the corrected peak frequency.

[0123] For example, step S620 can calculate and determine the corrected peak frequency according to the following formula. :

[0124] ;

[0125] in, It is the frequency of the attenuation point on the right. It is the frequency of the attenuation point on the left.

[0126] It should be noted that, given m transmission peaks, the m corrected peak frequencies can be calculated. .

[0127] S630, calculate the average value of the peak frequency spacing based on the corrected peak frequency and the number of transmission peaks.

[0128] For example, in step S630, the average value of the peak frequency spacing can be calculated and determined according to the following formula. :

[0129] ;

[0130] Where m is the number of transmission peaks; It is the corrected peak frequency.

[0131] S700 determines the thickness data of the sample at the target location based on the average value of the peak frequency spacing, the refractive index of the sample, and the speed of light.

[0132] For example, in step S700, the thickness data of the sample to be tested at the target location can be calculated and determined according to the following formula:

[0133] ;

[0134] Where n is the refractive index of the sample to be tested, and c is the speed of light. This represents the average value of the peak frequency spacing.

[0135] In this embodiment, a detection laser is emitted from a laser emitting device and then incident on the detection probe of a high-frequency power meter after passing through the target position of the sample under test. This achieves non-contact measurement of the thickness data at the target position of the sample under test, without damaging the surface finish of the sample, thus improving product yield. Furthermore, this application can acquire light intensity data and construct an initial and target optical information matrix using a high-frequency power meter based on a simple optical path without the need for a spectrometer. The thickness measurement range is not limited by the capabilities of the dispersive lens and spectrometer, effectively increasing both the measurable thickness range and measurement accuracy. In addition, this application determines the target power loss matrix based on the initial and target optical information matrices and identifies the transmission peak matrix to determine the average peak frequency spacing. Then, based on the average peak frequency spacing, the refractive index of the sample under test, and the speed of light, the thickness data of the sample under test at the target position is directly calculated. The test system setup and calculation method are relatively simple, requiring no high-precision scanning or complex phase-shifting algorithms, thereby improving measurement efficiency. With the combined effect of the above technical features, this application can realize non-contact thickness measurement of the sample to be tested, and can effectively improve the measurement accuracy and measurement efficiency of non-contact thickness measurement.

[0136] For example, the scanning wavelength range in the embodiments of this application is set according to different samples to be tested; for example, if the scanning wavelength range is set to 2nm and the light source scanning speed is set to 10nm / s, then the detection time required to measure the single-point thickness of the sample to be tested is less than 0.5s.

[0137] In some embodiments, the sample holder is mounted on a moving platform; the number of samples to be tested is multiple. See also... Figure 6 The glass thickness measurement method also includes the following steps S810~S830.

[0138] S810, multiple samples to be tested are laid flat on the loading fixture.

[0139] The S820 is a translational moving platform that allows the detection laser to sequentially transmit through each sample to be tested, and constructs a target light information matrix corresponding to each sample.

[0140] S830 measures the thickness data of each sample according to the target light information matrix corresponding to each sample.

[0141] In some embodiments, the loading clamp is mounted on a mobile platform. See also Figure 7 The glass thickness measurement method also includes the following steps S910~S940.

[0142] S910, place the sample to be tested on the loading fixture.

[0143] The S920 is a translational moving platform that allows the detection laser to sequentially transmit through multiple detection positions on the sample to be tested, and constructs a target light information matrix corresponding to each detection position.

[0144] S930 measures the thickness data of each detection position based on the target light information matrix corresponding to each detection position.

[0145] S940 determines the thickness of the sample to be tested based on the average thickness data from multiple detection locations.

[0146] This application also provides a glass thickness measurement system according to some embodiments; this glass thickness measurement system can be used to perform the glass thickness measurement methods in the above embodiments. The glass thickness measurement system also possesses all the technical advantages of the aforementioned glass thickness measurement methods. It should be noted that the parts that are the same as or corresponding to the above embodiments can be referred to the corresponding descriptions of the above embodiments, and will not be described in detail below.

[0147] In some embodiments, please refer to Figure 8 The glass thickness measurement system includes a laser emitting device, a sample holder 21, a high-frequency power meter 3, a matrix construction module 4, a data processing module 5, and a calculation module 6. The laser emitting device includes a light source 11 and a first light outlet 12; the light source 11 provides the detection laser; the first light outlet 12 is connected to the light source 11 and emits the detection laser; the sample holder 21 carries the sample S to be measured; the high-frequency power meter 3 includes a detection probe 31, with the first light outlet 12 and the detection probe 31 located on opposite sides of the sample holder 21; the high-frequency power meter 3 is configured to: when the sample holder 21 is not carrying a sample, sample the detection laser passing through the sample holder 21 and directly incident on the detection probe 31 to obtain first light intensity data at multiple wavelength sampling points; after placing the sample S on the sample holder 21, sample the detection laser that passes through the target position of the sample S and is incident on the detection probe 31 to obtain second light intensity data at multiple wavelength sampling points; the matrix construction module 4, data processing module 5, and calculation module 6. The matrix construction module 4 is connected to the high-frequency power meter 3 and is configured to: construct an initial optical information matrix based on multiple wavelength sampling points and the first light intensity data; and construct a target optical information matrix based on multiple wavelength sampling points and the second light intensity data. The data processing module 5 is connected to the matrix construction module 4 and is configured to: determine the target power loss matrix based on the target optical information matrix and the initial optical information matrix. The calculation module 6 is connected to the data processing module 5 and is configured to: identify and obtain multiple transmission peaks and their corresponding peak frequencies using a peak-finding algorithm based on the target power loss matrix to obtain a transmission peak matrix; determine the average value of the peak frequency spacing based on the transmission peak matrix; and determine the thickness data of the sample S at the target position based on the average value of the peak frequency spacing, the refractive index of the sample S to be tested, and the speed of light.

[0148] For example, the first output port 12 includes a collimator.

[0149] For example, the laser emitting device also includes a circulator 14. The circulator 14 is connected to the light source 11 and the collimator.

[0150] In some embodiments, please refer to Figure 9 The data processing module 5 includes a first determining unit 51, a matrix transformation unit 52, and a smoothing processing unit 53. The first determining unit 51 is configured to: determine a first power loss matrix in the wavelength domain based on the first light intensity data and the second light intensity data; the matrix transformation unit 52 is connected to the first determining unit 51 and is configured to: transform the first power loss matrix from the wavelength domain to the frequency domain to determine a second power loss matrix in the frequency domain; the smoothing processing unit 53 is connected to the matrix transformation unit 52 and is configured to: perform data smoothing processing on the second power loss matrix using a smoothing shift algorithm to determine a target power loss matrix.

[0151] In some embodiments, please refer to Figure 10 The calculation module 6 includes a second determining unit 61, a third determining unit 62, and a first calculation unit 64. The second determining unit 61 is configured to: determine the right-side attenuation point frequency and the left-side attenuation point frequency corresponding to each transmission peak in the transmission peak matrix using an interpolation algorithm based on the transmission peak matrix and the attenuation coefficient; the third determining unit 62 is connected to the second determining unit 61 and is configured to: determine the corrected peak frequency corresponding to each transmission peak based on the right-side attenuation point frequency and the left-side attenuation point frequency; the first calculation unit 64 is connected to the third determining unit 62 and is configured to: calculate the average peak frequency spacing based on the corrected peak frequency and the number of transmission peaks.

[0152] In some embodiments, please refer to Figure 11 The first light outlet 12 includes a collimator; the laser emitting device also includes a collimator fine-tuning mechanism 13 connected to the collimator; the glass thickness measurement system also includes a fixture fine-tuning mechanism 22 and an optical path calibration module 7. The fixture fine-tuning mechanism 22 is located at the bottom of the carrier fixture 21 and is used to adjust the tilt angle of the carrier fixture 21; the optical path calibration module 7 is connected to the collimator fine-tuning mechanism 13 and the fixture fine-tuning mechanism 22, and is configured to: when the carrier fixture 21 is not carrying a sample, adjust the collimator fine-tuning mechanism 13 so that the emission direction of the detection laser is perpendicular to the photosensitive surface of the detection probe 31; when the calibration sample is placed on the carrier fixture 21, adjust the fixture fine-tuning mechanism 22 so that the target surface of the calibration sample is perpendicular to the emission direction of the detection laser.

[0153] In some embodiments, please refer to Figure 8The laser emitting device also includes a second output port 15, and the high-frequency power meter 3 further includes a calibration probe 32. The second output port 15 is connected to the circulator 14 and is used to emit calibration light. The calibration probe 32 is used to receive the calibration light to initialize or periodically calibrate the perpendicular accuracy between the detection laser and the sample S under test.

[0154] In some embodiments, the glass thickness measurement system further includes a moving platform 23. A loading fixture 21 is disposed on the moving platform 23; the moving platform 23 is used to move horizontally to adjust the position of the loading fixture 21.

[0155] For example, mobile platform 23 can be an XY mobile platform.

[0156] In the description of this specification, references to terms such as "some embodiments," "some examples," "exemplarily," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative descriptions of the above terms do not necessarily refer to the same embodiments or examples.

[0157] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0158] The embodiments described above are merely examples of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application.

Claims

1. A method for measuring glass thickness, characterized in that, include: The first light output port of the laser emitting device and the detection probe of the high-frequency power meter are placed on both sides of the loading fixture, respectively. When the sample is not supported on the loading fixture, a detection laser is emitted through the first light outlet so that the detection laser passes through the loading fixture and directly enters the detection probe. The first light intensity data at multiple wavelength sampling points is obtained through the high-frequency power meter to construct an initial light information matrix. The sample to be tested is placed on the carrier fixture, and the detection laser is transmitted through the target position of the sample to be tested and then incident on the detection probe. The second light intensity data at multiple wavelength sampling points is obtained through the high-frequency power meter to construct the target light information matrix. Based on the target optical information matrix and the initial optical information matrix, the target power loss matrix is ​​determined; Based on the target power loss matrix, a peak-finding algorithm is used to identify and obtain multiple transmission peaks and the peak frequency corresponding to each transmission peak, so as to obtain the transmission peak matrix. Based on the transmission peak matrix, determine the average value of the peak frequency spacing; The thickness data of the sample at the target location is determined based on the average value of the peak frequency spacing, the refractive index of the sample under test, and the speed of light.

2. The glass thickness measurement method according to claim 1, characterized in that, The step of determining the target power loss matrix based on the target optical information matrix and the initial optical information matrix includes: Based on the first light intensity data and the second light intensity data, determine the first power loss matrix in the wavelength domain; The first power loss matrix is ​​transformed from the wavelength domain to the frequency domain to determine the second power loss matrix in the frequency domain. The second power loss matrix is ​​smoothed using a smoothing algorithm to determine the target power loss matrix.

3. The glass thickness measurement method according to claim 1, characterized in that, Determining the average frequency spacing of transmission peaks based on the transmission peak matrix includes: Based on the transmission peak matrix and attenuation coefficient, an interpolation algorithm is used to determine the right attenuation point frequency and the left attenuation point frequency corresponding to each transmission peak in the transmission peak matrix. Based on the right attenuation point frequency and the left attenuation point frequency, determine the corrected peak frequency corresponding to each transmission peak; The average value of the peak frequency spacing is calculated based on the corrected peak frequency and the number of transmission peaks.

4. The glass thickness measurement method according to claim 1, characterized in that, The first light-emitting port includes a collimator, and the laser emitting device further includes a collimator fine-tuning mechanism connected to the collimator; the bottom of the loading fixture is provided with a fixture fine-tuning mechanism; after the first light-emitting port of the laser emitting device and the detection probe of the high-frequency power meter are respectively placed on both sides of the loading fixture, and before the first light intensity data at multiple wavelength sampling points are obtained through the high-frequency power meter to construct an initial light information matrix, the glass thickness measurement method further includes: When the sample is not supported on the loading fixture, the detection laser is emitted through the collimator, and the collimator fine-tuning mechanism is adjusted so that the emission direction of the detection laser is perpendicular to the photosensitive surface of the detection probe. The calibration sample is placed on the carrier fixture, so that the detection laser passes through the calibration sample and then enters the detection probe. The fixture fine-tuning mechanism is adjusted so that the target surface of the calibration sample is perpendicular to the emission direction of the detection laser. Remove the calibration sample.

5. The glass thickness measurement method according to claim 1, characterized in that, The loading fixture is mounted on a mobile platform; the number of samples to be tested is multiple; the glass thickness measurement method further includes: Multiple samples to be tested are laid flat on the loading fixture; The moving platform is translated so that the detection laser sequentially transmits through each of the test samples, and the target light information matrix corresponding to each test sample is constructed respectively; Based on the target light information matrix corresponding to each of the test samples, the thickness data of each test sample is measured.

6. The glass thickness measurement method according to claim 1, characterized in that, The loading fixture is mounted on a mobile platform; the glass thickness measurement method further includes: The sample to be tested is placed on the loading fixture; The moving platform is translated so that the detection laser sequentially transmits through multiple detection positions on the sample to be tested, and the target light information matrix corresponding to each detection position is constructed respectively; Based on the target light information matrix corresponding to each detection position, the thickness data of each detection position is measured respectively; The thickness of the sample to be tested is determined based on the average of the thickness data from multiple detection locations.

7. A glass thickness measurement system, characterized in that, include: A laser emitting device, including a light source and a first light outlet; The light source is used to provide detection laser; the first light outlet is connected to the light source and is used to emit detection laser. A sample holder is used to hold the sample to be tested. A high-frequency power meter includes a detection probe, with a first light outlet and the detection probe located on opposite sides of a sample holder. The high-frequency power meter is configured to: sample the detection laser light passing through the sample holder and directly incident on the detection probe when the sample holder is not carrying a sample, to obtain first light intensity data at multiple wavelength sampling points; and after the sample to be tested is placed on the sample holder, sample the detection laser light incident on the detection probe at the target position after passing through the sample to be tested, to obtain second light intensity data at multiple wavelength sampling points. The matrix construction module, connected to the high-frequency power meter, is configured to: construct an initial optical information matrix based on the multiple wavelength sampling points and the first light intensity data; and construct a target optical information matrix based on the multiple wavelength sampling points and the second light intensity data. The data processing module, connected to the matrix construction module, is configured to: determine the target power loss matrix based on the target optical information matrix and the initial optical information matrix; The calculation module, connected to the data processing module, is configured to: based on the target power loss matrix, use a peak-finding algorithm to identify and obtain multiple transmission peaks and the peak frequencies corresponding to each transmission peak to obtain a transmission peak matrix; based on the transmission peak matrix, determine the average value of the peak frequency spacing; and determine the thickness data of the sample under test at the target position according to the average value of the peak frequency spacing, the refractive index of the sample under test, and the speed of light.

8. The glass thickness measurement system according to claim 7, characterized in that, The data processing module includes: The first determining unit is configured to: determine a first power loss matrix in the wavelength domain based on the first light intensity data and the second light intensity data; The matrix transformation unit, connected to the first determining unit, is configured to: transform the first power loss matrix from the wavelength domain to the frequency domain to determine the second power loss matrix in the frequency domain; The smoothing processing unit, connected to the matrix transformation unit, is configured to: perform data smoothing processing on the second power loss matrix using a smoothing shift algorithm to determine the target power loss matrix.

9. The glass thickness measurement system according to claim 7, characterized in that, The computing module includes: The second determining unit is configured to: determine the right attenuation point frequency and the left attenuation point frequency corresponding to each transmission peak in the transmission peak matrix using an interpolation algorithm based on the transmission peak matrix and the attenuation coefficient. The third determining unit, connected to the second determining unit, is configured to: determine the corrected peak frequency corresponding to each transmission peak based on the right attenuation point frequency and the left attenuation point frequency, respectively. The first calculation unit, connected to the third determination unit, is configured to calculate the average value of the peak frequency spacing based on the corrected peak frequency and the number of transmission peaks.

10. The glass thickness measurement system according to claim 7, characterized in that, The first light output port includes a collimator; the laser emitting device further includes a collimator fine-tuning mechanism connected to the collimator; The glass thickness measurement system also includes: A clamp fine-tuning mechanism, located at the bottom of the loading clamp, is used to adjust the tilt angle of the loading clamp; The optical path calibration module, connected to the collimator fine-tuning mechanism and the fixture fine-tuning mechanism, is configured to: adjust the collimator fine-tuning mechanism so that the emission direction of the detection laser is perpendicular to the photosensitive surface of the detection probe when the sample is not mounted on the fixture; and adjust the fixture fine-tuning mechanism so that the target surface of the calibration sample is perpendicular to the emission direction of the detection laser when the calibration sample is placed on the fixture.

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