CN106918597B

CN106918597B - Film quality detection method and film quality detection system

Info

Publication number: CN106918597B
Application number: CN201510993892.4A
Authority: CN
Inventors: 张健; 冯礼; 秦庆旺; 冯治国; 卢继兵; 韩英魁; 朱强
Original assignee: China Banknote Printing and Minting Corp; Institute of Printing Science and Technology Peoples Bank of China
Current assignee: China Banknote Printing Technology Research Institute Co ltd; China Banknote Printing and Minting Group Co Ltd
Priority date: 2015-12-25
Filing date: 2015-12-25
Publication date: 2021-03-02
Anticipated expiration: 2035-12-25
Also published as: CN106918597A

Abstract

The invention provides a film quality detection method and a film quality detection system, wherein the film quality detection method comprises the following steps: selecting a target imaging mode from a plurality of preset imaging modes according to the received detection command; acquiring image data of a plurality of positions of a film to be detected in a target imaging mode; and determining whether the quality of the film to be detected at each position is qualified according to the attribute of the image data of each position in the plurality of positions, so as to determine whether the quality of the film to be detected is qualified. By the technical scheme, a proper film quality detection mode can be automatically selected for a user, so that the film detection efficiency and quality are improved.

Description

Film quality detection method and film quality detection system

Technical Field

The invention relates to the technical field of quality detection, in particular to a film quality detection method and a film quality detection system.

Background

In the related art, there are many methods for detecting the quality of a film, and the types of the film and the application scenes to which the methods are applied are different. At present, a user generally selects which method is adopted for detecting the quality of the thin film, however, the selection has great subjectivity and uncertainty, and the problems of detection deviation and the like easily occur.

Therefore, a new technical solution is needed, which can automatically select a suitable film quality detection mode for the user.

Disclosure of Invention

Based on the problems, the invention provides a new technical scheme which can automatically select a proper film quality detection mode for a user.

In view of the above, an aspect of the present invention provides a film quality detection method for a film quality detection system, including: selecting a target imaging mode from a plurality of preset imaging modes according to a received detection command, wherein the detection command comprises a periodic acquisition command of a film to be detected or a command for acquiring data of the film to be detected according to a trigger signal; acquiring image data of a plurality of positions of the film to be detected by using the target imaging mode; determining whether the quality of the film to be detected at each position is qualified or not according to the attribute, the set shape, the set range value, the image high-value template and the image low-value template of the image data of each position in the plurality of positions and the threshold range after data conversion, so as to determine whether the quality of the film to be detected is qualified or not; wherein the plurality of imaging modalities includes: in the first imaging mode, reflected light or transmitted light of a narrow-band region of the film to be detected enters a light splitting component of the film quality detection system after being focused by a lens, and lights with different wavelengths after being split are spatially separated and projected to one or a group of area array grayscale cameras of the film quality detection system; in the second imaging mode, the specular reflection light of a narrow-band area of the film to be detected enters one or a group of gray scale or color linear array cameras of the film quality detection system after being focused by a lens; in a third imaging mode, after being focused by a lens, diffuse reflection light of a narrow-band area of the film to be detected enters one or a group of gray scale or color linear array cameras of the film quality detection system; in a fourth imaging mode, transmitted light of a narrow-band region of the film to be detected enters one or a group of gray scale or color linear array cameras of the film quality detection system after being focused by a lens; and the multiple imaging modes are used for respectively acquiring different optical characteristic images of the film to be detected.

In the technical scheme, a plurality of imaging modes can be preset in the system, so that when a detection command is received, the imaging mode suitable for the detection command is selected, namely, the film quality detection mode suitable for the detection command is selected, and whether the quality of the film is qualified or not is judged according to the detection result. When the quality of the film is detected, periodic image acquisition can be performed, and data can also be acquired when a trigger signal is received each time. Through the technical scheme, a proper film quality detection mode can be automatically selected for a user, so that the reliability of a film quality detection result is improved, and the efficiency and the quality of film detection are improved. The film in the technical scheme includes but is not limited to a liquid crystal film, a holographic dealumination security thread, an optically variable film, a plastic film, paper, cloth, calligraphy and painting and the like.

In the above technical solution, preferably, in the spectral imaging mode, reflected light or transmitted light of a narrow band region of the film to be detected enters a light splitting component of the film quality detection system after being focused by a lens of the film quality detection system, and lights with different wavelengths after being split are spatially separated and projected to an area array grayscale camera of the film quality detection system.

In the technical scheme, the spectrum acquisition system mainly comprises a light splitting component and an array gray scale camera, and an optical lens is arranged at the front end of the light splitting component. Reflected light or transmitted light of a narrow-band region of the film to be detected enters the light splitting component after being focused by the lens, and light with different wavelengths after light splitting is spatially separated and projected to a collecting unit of the area array gray-scale camera. Each two-dimensional image acquired by the area array gray-scale camera corresponds to spectral information of a narrow-band region, the image transversely corresponds to the transverse direction of the film to be detected, each line represents information of the narrow-band region at the corresponding wavelength of the line, the image longitudinally corresponds to different spectral wavelengths, each column represents spectral expansion information of a sub-region of the narrow-band region, and the size of a pixel value of the image represents the intensity of a certain wavelength.

In the above technical solution, preferably, the acquiring image data of a plurality of positions of the film to be detected by using the target imaging mode specifically includes: acquiring image data of the whole breadth width of the film to be detected for multiple times by using an image data acquisition device corresponding to the target imaging mode so as to acquire full-width image data of the film to be detected; or using an image data collector corresponding to the target imaging mode to collect image data of partial breadth width of the film to be detected for multiple times, wherein the image data collector is static or does reciprocating motion in the width direction.

In the technical scheme, different image acquisition means can be adopted to acquire image data according to actual requirements, specifically, the full-width image data of the film can be acquired, and the image data of partial breadth width of the film can also be acquired, wherein in the acquisition process, the static film can be subjected to image data acquisition by moving the image data acquisition device, and the static image acquisition device can also be subjected to image data acquisition of the moving film. That is, typical methods of spectrum acquisition include two types: firstly, the film moves along the longitudinal direction, the spectrum acquisition system is fixed, or (when the width of the spectrum acquisition narrow band is smaller than the width of the film) the spectrum acquisition system moves in a reciprocating way; secondly, the film is fixed, and the spectrum acquisition system moves once or for a plurality of times along one direction to complete the spectrum information acquisition of the whole film. In addition, the system can collect the spectral information according to the actual situation and the requirement and according to a specific motion mode. According to the technical scheme, diversified image acquisition means can better meet the requirements of a user on the detection film, the reliability of the film quality detection result is improved, the detection efficiency is convenient to improve, and the detection cost is reduced.

In the foregoing technical solution, preferably, attributes of the image data corresponding to different imaging modes are different, where the attributes of the image data corresponding to the spectral imaging mode include: a dominant wavelength, a half-wave width, a peak intensity, an energy integral, a dominant wavelength of a certain wavelength interval, a half-wave width of a certain wavelength interval, a peak value of a certain wavelength interval of the image dataIntensity, energy integral of a certain wavelength interval, CIE XYZ value, CIE L^*a^*b^*Value, CIE h_abAnd

values, and attributes of the image data corresponding to the reflection imaging mode and the transmission imaging mode include at least one or a combination of: the image data comprises a high-low value range of image data color, a high-low value image data template, the number of patterns, the integrity degree of the patterns and the similarity degree of the patterns.

In this technical solution, the spectral imaging mode, the reflective imaging mode, and the transmissive imaging mode all correspond to respective image data attributes, wherein the image data attributes corresponding to the spectral imaging mode include, but are not limited to, a dominant wavelength, a half-wave width, a peak intensity, an energy integral of the image data, a dominant wavelength of a certain wavelength interval, a half-wave width of a certain wavelength interval, a peak intensity of a certain wavelength interval, an energy integral of a certain wavelength interval, a CIE XYZ value, a CIE L^*a^*b^*Value, CIE h_abAnd

value, CIE is the color system, CIE XYZ, CIE L^*a^*b^*、CIE h_ab、

The image data attributes corresponding to the reflective imaging mode and the transmissive imaging mode include, but are not limited to, at least one of the following or a combination thereof: the image data comprises a high-low value range of image data color, a high-low value image data template, the number of patterns, the integrity degree of the patterns and the similarity degree of the patterns. Through the technical scheme, the quality of the film can be judged through various image data attributes, and the diversified judgment basis can enable the film quality detection result to be more accurate and comprehensive, so that the quality and the efficiency of film detection are improved.

In the above technical solution, preferably, the determining whether the quality of the film to be detected at each position is qualified specifically includes: according to the attribute of the image data of each position, calculating a comprehensive defect value of each position through a preset defect value calculation formula so as to determine whether the quality of the film to be detected at each position is qualified or not according to the comprehensive defect value of each position, wherein the preset defect value calculation formula is as follows:

wherein i represents a width direction in which the image data is acquired, j represents a length direction in which the image data is acquired, and w_nIn the range of [0,1]Indicating an nth oriented image data defect weight coefficient at each of said positions, Blobn (i, j) ranging from [0,255 []Indicating the n-th oriented image data defect value at said each location, TotolBlob (i, j) indicating said integrated defect value at said each location.

In the technical scheme, the defect value of the detection position of the film can be calculated through the preset defect value calculation formula, so that whether the quality of the film meets the requirement or not is judged according to the size of the defect value or the range of the defect value, the film quality detection result is more accurate and comprehensive, and the quality and the efficiency of film detection are improved.

In the above technical solution, preferably, before the determining whether the quality of the film to be detected at each position is qualified, the method further includes: determining a qualified data space and an unqualified data space of the image data according to the attribute of the image data of each position in the plurality of positions; setting a quality judging condition according to a boundary of the qualified data space and the unqualified data space, so as to determine whether the quality of the film to be detected is qualified or not according to the quality judging condition; and determining Blobn (i, j) of the image data according to the attribute of the image data, the qualified data space and the unqualified data space.

In the technical scheme, when the defect value of the detection position of the film is calculated through the preset defect value calculation formula, a qualified data space and an unqualified data space can be divided according to the image data attribute, so that whether the defect value is located in the qualified data space or the unqualified data space can be further judged, and a film quality detection result is obtained. Through the technical scheme, the divided qualified data space and the divided unqualified data space can enable the judgment of the range of the defect value to be more accurate, so that the film quality detection result is more accurate and comprehensive, and the quality and the efficiency of film detection are improved.

Another aspect of the present invention provides a film quality detecting system, including: the imaging mode selection unit is used for selecting a target imaging mode from a plurality of preset imaging modes according to a received detection command, wherein the detection command comprises a periodic acquisition command of a film to be detected or a command for acquiring data of the film to be detected according to a trigger signal; the image data acquisition unit acquires image data of a plurality of positions of the film to be detected in a target imaging mode; the quality judging unit is used for determining whether the quality of the film to be detected at each position is qualified or not according to the attribute, the set shape, the set range value, the image high-value template and the image low-value template of the image data of each position in the plurality of positions and the threshold range after data conversion so as to determine whether the quality of the film to be detected is qualified or not; wherein the plurality of imaging modalities includes: in the first imaging mode, reflected light or transmitted light of a narrow-band region of the film to be detected enters a light splitting component of the film quality detection system after being focused by a lens, and lights with different wavelengths after being split are spatially separated and projected to one or a group of area array grayscale cameras of the film quality detection system; in the second imaging mode, the specular reflection light of a narrow-band area of the film to be detected enters one or a group of gray scale or color linear array cameras of the film quality detection system after being focused by a lens; in a third imaging mode, after being focused by a lens, diffuse reflection light of a narrow-band area of the film to be detected enters one or a group of gray scale or color linear array cameras of the film quality detection system; in a fourth imaging mode, transmitted light of a narrow-band region of the film to be detected enters one or a group of gray scale or color linear array cameras of the film quality detection system after being focused by a lens; and the multiple imaging modes are used for respectively acquiring different optical characteristic images of the film to be detected.

In the above technical solution, preferably, the image data acquisition unit includes: the first acquisition unit is used for acquiring the image data of the whole breadth width of the film to be detected for multiple times by using an image data acquisition device corresponding to the target imaging mode so as to acquire the full-width image data of the film to be detected; and/or a second acquisition unit which acquires the image data of partial breadth width of the film to be detected for multiple times by using an image data acquisition unit corresponding to the target imaging mode, wherein the image data acquisition unit is static in the width direction or moves back and forth.

In the foregoing technical solution, preferably, attributes of the image data corresponding to different imaging modes are different, where the attributes of the image data corresponding to the spectral imaging mode include: dominant wavelength, half-wave width, peak intensity, energy integral, dominant wavelength of a certain wavelength interval, of the image data,Half wave width of a certain wavelength region, peak intensity of a certain wavelength region, energy integral of a certain wavelength region, CIE XYZ value, CIE L^*a^*b^*Value, CIE h_abAnd

value, CIE is the color system, CIE XYZ, CIE L^*a^*b^*、CIE h_ab、

In the foregoing technical solution, preferably, the quality determination unit is specifically configured to: according to the attribute of the image data of each position, calculating a comprehensive defect value of each position through a preset defect value calculation formula so as to determine whether the quality of the film to be detected at each position is qualified or not according to the comprehensive defect value of each position, wherein the preset defect value calculation formula is as follows:

In the above technical solution, preferably, the method further includes: before determining whether the quality of the film to be detected at each position is qualified, a judging condition setting unit determines a qualified data space and an unqualified data space of the image data according to the attribute of the image data at each position in the plurality of positions, and sets a quality judging condition according to a boundary of the qualified data space and the unqualified data space, so as to determine whether the quality of the film to be detected is qualified according to the quality judging condition; and a defect value determination unit that determines Blobn (i, j) of the image data based on the attribute of the image data, the qualified data space, and the unqualified data space.

Through the technical scheme, a proper film quality detection mode can be automatically selected for a user, so that the reliability of a film quality detection result is improved, and the efficiency and the quality of film detection are improved.

Drawings

FIG. 1 shows a flow diagram of a method of film quality inspection according to one embodiment of the invention;

FIG. 2 shows a block diagram of a thin film quality inspection system according to one embodiment of the invention;

FIG. 3 shows a schematic diagram of a thin film quality inspection system according to another embodiment of the present invention;

FIG. 4 shows a schematic diagram of the various imaging systems of FIG. 3;

FIG. 5 shows a linear light source configuration diagram of a spectral imaging system;

fig. 6 shows a schematic diagram of the imaging effect of the spectral imaging system.

Detailed Description

In order that the above objects, features and advantages of the present invention can be more clearly understood, a more particular description of the invention will be rendered by reference to the appended drawings. It should be noted that the embodiments and features of the embodiments of the present application may be combined with each other without conflict.

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention, however, the present invention may be practiced in other ways than those specifically described herein, and therefore the scope of the present invention is not limited by the specific embodiments disclosed below.

Fig. 1 shows a flow chart of a film quality inspection method according to an embodiment of the present invention.

As shown in fig. 1, a film quality inspection method according to an embodiment of the present invention is used in a film quality inspection system, and includes:

102, selecting a target imaging mode from a plurality of preset imaging modes according to a received detection command, wherein the detection command comprises a periodic acquisition command of a film to be detected or a command for acquiring data of the film to be detected according to a trigger signal;

104, acquiring image data of a plurality of positions of the film to be detected in a target imaging mode;

and step 106, determining whether the quality of the film to be detected at each position is qualified according to the attribute, the set shape, the set range value, the image high-value template and the image low-value template of the image data of each position in the plurality of positions and the threshold range after data conversion, so as to determine whether the quality of the film to be detected is qualified.

Wherein the plurality of imaging modalities includes: in the first imaging mode, reflected light or transmitted light of a narrow-band region of the film to be detected enters a light splitting component of the film quality detection system after being focused by a lens, and lights with different wavelengths after being split are spatially separated and projected to one or a group of area array grayscale cameras of the film quality detection system; in the second imaging mode, the specular reflection light of a narrow-band area of the film to be detected enters one or a group of gray scale or color linear array cameras of the film quality detection system after being focused by a lens; in a third imaging mode, after being focused by a lens, diffuse reflection light of a narrow-band area of the film to be detected enters one or a group of gray scale or color linear array cameras of the film quality detection system; in a fourth imaging mode, transmitted light of a narrow-band region of the film to be detected enters one or a group of gray scale or color linear array cameras of the film quality detection system after being focused by a lens; and the multiple imaging modes are used for respectively acquiring different optical characteristic images of the film to be detected.

In the above technical solution, preferably, step 104 specifically includes: acquiring image data of the whole breadth width of the film to be detected for multiple times by using an image data acquisition device corresponding to a target imaging mode so as to acquire full-width image data of the film to be detected; or using an image data collector corresponding to a target imaging mode to collect image data of partial breadth width of the film to be detected for multiple times, wherein the image data collector is static or does reciprocating motion in the width direction.

In the above technical solution, preferably, the attributes of the image data corresponding to different imaging modes are different, where the attributes of the image data corresponding to the spectral imaging mode include: dominant wavelength, half wave width, peak intensity, energy integral, CIE XYZ value, CIE L of image data^*a^*b^*Value, CIE h_abAnd

values, and image data corresponding to the reflective imaging mode and the transmissive imaging modeThe attributes of (a) include at least one or a combination of: the image data comprises a high-low value range of image data color, a high-low value image data template, the number of patterns, the integrity degree of the patterns and the similarity degree of the patterns.

value, CIE is the color system, CIE XYZ, CIE L^*a^*b^*、CIE h_ab、

In the above technical solution, preferably, step 106 specifically includes: according to the attribute of the image data of each position, calculating the comprehensive defect value of each position through a preset defect value calculation formula so as to determine whether the quality of the film to be detected at each position is qualified or not according to the comprehensive defect value of each position, wherein the preset defect value calculation formula is as follows:

wherein i represents a width direction when the image data is acquired, j represents a length direction of the acquired image data, and w_nIn the range of [0,1]The n-th oriented image data defect weight coefficient at each position is expressed, and the range of Blobn (i, j) is [0,255%]Indicating the n-th oriented image data defect value at each location, TotolBlob (i, j) indicates the integrated defect value at each location.

In the above technical solution, before step 106, preferably, the method further includes: determining a qualified data space and an unqualified data space of the image data according to the attribute of the image data at each of the plurality of positions; setting a quality judging condition according to a boundary of the qualified data space and the unqualified data space so as to determine whether the quality of the film to be detected is qualified or not according to the quality judging condition; and determining Blobn (i, j) of the image data according to the attribute of the image data, the qualified data space and the unqualified data space.

FIG. 2 shows a block diagram of a thin film quality inspection system according to one embodiment of the invention.

As shown in fig. 2, a film quality inspection system 200 according to an embodiment of the present invention includes: the imaging mode selection unit 202 selects a target imaging mode from a plurality of preset imaging modes according to the received detection command, wherein the detection command comprises a periodic acquisition command of the film to be detected or a command for acquiring data of the film to be detected according to a trigger signal; the image data acquisition unit 204 is used for acquiring image data of a plurality of positions of the film to be detected in a target imaging mode; the quality determination unit 206 determines whether the quality of the film to be detected at each position is qualified according to the attribute, the set shape, the set range value, the image high value template and the image low value template of the image data at each position in the plurality of positions and the threshold range after data conversion, so as to determine whether the quality of the film to be detected is qualified.

In the above technical solution, preferably, the image data acquisition unit 204 includes: the first acquisition unit 2042 acquires image data of the entire width of the film to be detected for multiple times by using an image data acquisition device corresponding to a target imaging mode to acquire full-width image data of the film to be detected; and/or a second collecting unit 2044, which collects the image data of a part of the width of the film to be detected multiple times by using an image data collector corresponding to the target imaging mode, wherein the image data collector is stationary in the width direction or performs reciprocating motion.

In the above technical solution, preferably, the attributes of the image data corresponding to different imaging modes are different, where the attributes of the image data corresponding to the spectral imaging mode include: the attribute of the image data corresponding to the dominant wavelength, the half-wave width, the peak intensity, the energy integral, the dominant wavelength of a certain wavelength interval, the half-wave width of a certain wavelength interval, the peak intensity of a certain wavelength interval, the energy integral of a certain wavelength interval, the CIE XYZ value, the CIE L a b value, the CIE hab and C ab value, and the reflection imaging mode and the transmission imaging mode includes at least one of the following or a combination thereof: the image data comprises a high-low value range of image data color, a high-low value image data template, the number of patterns, the integrity degree of the patterns and the similarity degree of the patterns.

In the technical scheme, the spectral imaging mode, the reflection imaging mode and the transmission imaging mode are all pairedThe image data attributes corresponding to the spectral imaging method should include, but not limited to, dominant wavelength, half-wave width, peak intensity, energy integral, dominant wavelength in a certain wavelength region, half-wave width in a certain wavelength region, peak intensity in a certain wavelength region, energy integral in a certain wavelength region, CIE XYZ value, CIE L^*a^*b^*Value, CIE h_abAnd

value, CIE is the color system, CIE XYZ, CIE L^*a^*b^*、CIE h_ab、

In the foregoing technical solution, preferably, the quality determination unit 206 is specifically configured to: according to the attribute of the image data of each position, calculating the comprehensive defect value of each position through a preset defect value calculation formula so as to determine whether the quality of the film to be detected at each position is qualified or not according to the comprehensive defect value of each position, wherein the preset defect value calculation formula is as follows:

wherein i represents a width direction when the image data is acquired, j represents a length direction of the acquired image data, and w_nIn the range of [0,1]The n-th image data defect-oriented weighting coefficient at each position, Blobn (i, j) is expressed byIs enclosed as [0,255]Indicating the n-th oriented image data defect value at each location, TotolBlob (i, j) indicates the integrated defect value at each location.

In the above technical solution, preferably, the method further includes: a determination condition setting unit 208 that determines a qualified data space and an unqualified data space of the image data according to the attribute of the image data at each of the plurality of positions before determining whether the quality of the film to be detected at each position is qualified, and sets a quality determination condition according to a boundary between the qualified data space and the unqualified data space, so as to determine whether the quality of the film to be detected is qualified according to the quality determination condition; and a defect value determination unit 210 that determines blob n (i, j) of the image data based on the attribute of the image data, the qualified data space, and the unqualified data space.

Fig. 3 shows a schematic structural diagram of a film quality detection system according to another embodiment of the present invention.

As shown in fig. 3, a film quality detecting system according to another embodiment of the present invention for detecting the quality of a liquid crystal film, a holographic dealuminated security thread, an optically variable film, a plastic film, paper, cloth, calligraphy and painting, etc., includes: the device comprises a roller, a motion control system, a spectrum acquisition and processing subsystem, a reflection image acquisition and processing subsystem, a transmission image acquisition and processing subsystem, a quality marking subsystem, an image analysis master station system and a post-process product processing system.

The film quality detection system can automatically detect the quality of film products and comprises two detection methods:

the method comprises the following steps: collecting the spectral image and the surface image of the film in operation, automatically detecting and judging the quality of the film through digital image processing, determining whether the product quality is qualified, obtaining a product detection conclusion in time, carrying out quality marking on line, or storing detection result data information, or transmitting the detection result data information to a subsequent process, and carrying out treatment such as integral invalidation, local invalidation, defect repair and the like according to the detection result in the subsequent process. Wherein, the detection result includes: whether the whole is qualified, the longitudinal position and the transverse position of the local defect, or the quality mark of a detection system, and the like.

The second method comprises the following steps: the detected object can be fixed on the flat plate or fixed at two ends, the image collector scans the detected object in motion to obtain image data for analysis and detection, and the specific processing method is the same as that of the method I.

In addition, the object detected by the film quality detection system can be a whole film product, a plurality of film products or a cut strip product.

The film quality detection system mainly comprises a motion control system, a roller and other motion components, at least one set of spectrum acquisition and processing subsystem, at least one set of reflection image acquisition and processing subsystem or transmission image acquisition and processing subsystem and an image analysis master station system. And may also include a quality marking subsystem that is connectable to the post-process product handling system.

Each image acquisition and processing subsystem may acquire images at a fixed frequency (or period) or via a trigger signal of the motion control system, the frequency (or period) of the trigger signal being proportional to the product running speed. Each acquisition and processing subsystem is analyzed and processed through an embedded circuit board or a computer. The basic width of the film detection of the film quality detection system is 0.2m to 1m, and of course, a narrower film or a wider film after fine cutting can be detected, and the running speed is less than or equal to 150 m/min.

Fig. 4 shows a schematic diagram of the respective imaging system of fig. 3.

As shown in fig. 4, the spectral imaging system can acquire spectral quality information of the thin film. The light emitted by the light source 1 has a wide frequency range and smooth spectral lines, the light source 1 can be one of a white light source, an ultraviolet light source and an infrared light source, or a combination of two or three of the white light source, the ultraviolet light source and the infrared light source, the maximum illumination area of the light source 1 is 1200mm x 30mm, the illuminance uniformity is greater than or equal to 95%, the focal length is 200mm, the focal length can be adjusted according to requirements, the total luminous flux is 68000lm, the peak luminous flux is 100000lm, the maximum power is 500W in a continuous working mode, the power of the light source can be dynamically and steplessly adjusted, the peak power is 3000W in a trigger working mode, and the shortest switching period of the trigger mode can reach 0.1 ms.

The Light Emitting part is formed by arranging a plurality of LEDs (Light Emitting diodes), and can be all white LEDs, or white LEDs and ultraviolet LEDs are alternately arranged, staggered or parallel arranged, or white LEDs and infrared LEDs are alternately arranged, staggered or parallel arranged, or ultraviolet LEDs, white LEDs and infrared LEDs are alternately arranged, staggered or parallel arranged. The linear light source structure is shown in fig. 5, the LED is fixed on the light source base plate, the columnar optical element covers the LED, and the emitted light is converged into high-intensity linear light, wherein, the incident light path can be provided with a depolarizer.

As shown in fig. 4, the spectroscopy assembly collects spectral data after reflection (or transmission) by the thin film. Under the imaging mode that the roller drives the film, the focusing surface of the optical system can be a suspended position after the film is separated from the roller, and can also be positioned on the roller. In the reflective imaging mode, the incident angle of the light source is 0 to 15 °,1 to 3 light sources can be used for illumination from different incident angles, and the reflective angle of the spectrum acquisition system is 0 to 15 °. Under the transmission imaging mode, the incident angle of the light source is-15 degrees to +15 degrees, 1 to 3 light sources can be used for irradiating from different incident angles, and the included angle between the light rays entering the spectrum light splitting and collecting system and the normal is-15 degrees to +15 degrees. The front end of the light splitting component is provided with a lens, the lens has good passing performance for all color lights, the light passing through the lens enters a slit of the light splitting device, the light with different wavelengths is uniformly spread by the light splitting device in space after passing through the slit, and the maximum spectral resolution after spreading can reach 1nm and the minimum spectral resolution is 20 nm. The area array gray level camera at the rear end collects spectral data, and the area array gray level camera has a continuous and smooth spectral response curve.

The reflected light imaging system can be the reflection method shown in fig. 4, and can also be a light source 1 arranged on the other side of the film to collect the transmission spectrum. The light source 1 is at an angle in the range of 0 to 80 degrees to the normal. When the angle of the light source 1 to the normal is 0 degree or close to 0 degree, the half-transmitting and half-reflecting prism is used for imaging. The spectral range of the light split by the light splitting component is 200nm to 1000 nm.

The reflected light imaging system is used for collecting a reflected light image of the film. The light source 2 is one of a white light source, an ultraviolet light source and an infrared light source, or a combination of two or three of the white light source, the ultraviolet light source and the infrared light source, the range of the incident angle is 0 to 90 degrees, and when the incident angle is 0 degree, the semi-transparent semi-reflective prism can be used for imaging. Polarizing optics may be provided in the path of the incident light as desired. The camera 2 is a color or gray scale line camera or an area gray scale camera. The optical axis of the camera 2 may coincide with the normal, or be at any other angle. According to the needs, the front end of the camera 2 can be provided with a polarization optical device to realize the polarization imaging effect.

As further shown in FIG. 4, a transmitted light imaging system is used to acquire transmitted light images of the film. The light source 3 is one of a white light source, an ultraviolet light source and an infrared light source, or a combination of two or three of them, and the incident angle of the light source 3 may be vertical incidence or an angle between 0 degree and 90 degrees. The optical axis of the camera 3 may coincide with the normal, or be at any other angle. According to the needs, the front end of the camera 3 can be provided with a polarization optical device to realize the polarization imaging effect.

As shown in fig. 6, the spectrum collection system mainly includes a light splitting component and an array gray scale camera, and an optical lens is disposed at the front end of the light splitting component. Reflected light or transmitted light of a narrow-band region of the film to be detected enters the light splitting component after being focused by the lens, and light with different wavelengths after light splitting is spatially separated and projected to a collecting unit of the area array gray-scale camera. Each two-dimensional image acquired by the area array gray-scale camera corresponds to spectral information of a narrow-band region, the image transversely corresponds to the transverse direction of the film to be detected, each line represents information of the narrow-band region at the corresponding wavelength of the line, the image longitudinally corresponds to different spectral wavelengths, each column represents spectral expansion information of a sub-region of the narrow-band region, and the size of a pixel value of the image represents the intensity of a certain wavelength.

Specifically, the camera for spectral imaging is an area-array digital camera, and each column of the camera corresponds to the spectral expansion curve of a small film. The horizontal physical size of the shooting object is Width, the resolution of the camera is N pixels, the horizontal spectral resolution is Width/Npixel, the maximum system Width is 1m, the maximum Npixel is 2048, and the maximum horizontal spatial resolution is 0.49mm, and the lower resolution can be obtained by arranging adjacent N (2, 3, 4, …) pixels for combination. Under the normal working state of the system, the transverse spatial resolution is 0.49mm to 49 mm. Under special working conditions, 1 to 20 points can be selected arbitrarily, and the spectral characteristics of the film can be tracked, analyzed and detected. The maximum longitudinal pixel resolution of the area-array gray-scale camera is 1088, and lower resolution can be obtained through pixel combination. Each column of the image is spread corresponding to the spectrum of a certain block of the shooting object, the spread spectrum can maximally contain the wavelength range of 300-1200 nm, and a part of the spectrum can be collected according to the requirement, such as the wavelength range of 380-780 nm. And selecting a certain number of points from the acquired data, wherein the wavelength resolution is 0.5-10 nm, and generally not less than 40 points, and the points are used for spectrum calculation and detection. Under special working conditions, 1 to 40 points of spectral data can be selected for tracking, analyzing and detecting the spectral characteristics of the film.

The spectral imaging system can acquire the spectrum of the whole breadth width range, and the system frequently acquires spectral images while the product moves, so that the discontinuous or continuous full-width spectrum acquisition is realized; or the spectrum of partial breadth width range can be collected, and the system frequently collects the spectrum image while the product moves, thereby realizing the spectrum collection of the discontinuous or continuous partial width range; or the spectrum of partial breadth width range is collected, the spectrum imaging system moves back and forth in the width direction while the product moves, the system frequently collects spectrum images, and spectrum collection of multiple positions in the width direction and at intervals in the length direction is realized; or a plurality of sets of light splitting assemblies and cameras are used for collecting spectral images at different positions and respectively processing the spectral images or processing the spectral images after splicing the spectral images.

The exposure time of the spectral imaging system is Ex _ time, the system running speed is v, the travelling direction spectral resolution is v/Ex _ time, the maximum speed of the system is v 150m/min, the minimum exposure time of the system is Ex _ time 1ms, the corresponding travelling direction resolution is 2.5mm, and higher travelling direction resolution can be obtained by reducing the running speed or the travelling direction resolution is reduced by increasing the exposure time. And under the continuous exposure working state of the system, the spectral resolution in the advancing direction is 2.5mm to 100 mm.

The system may interval exposures for an interval time of Ex skip, which may range from 0s to 10 s.

In addition, the spectrum detection range is 200nm to 1000nm, and two detection methods of a unimodal spectrum and a multimodal spectrum are included according to the characteristics of the detection object:

(one) single peak spectrum

The system automatically analyzes to obtain spectral indexes such as dominant wavelength, half-wave width, spectral intensity (reflectivity), segmented integral energy and the like of each transverse nub of the film, whether the detected spectrum is qualified or not is judged, and a spectrum detection logical relation chart is shown in table 1. And meanwhile, calculating the value of each index exceeding the parameter range to obtain a defect value.

TABLE 1

Measured value	Parameter range	Single item detection conclusion
			Dominant wavelength/nm	[Peak_low,Peak_high]	Pass/fail
Half wave width/nm	[Wave_min,Wave_max]	Pass/fail
			Strength of	[Strength_min,Strength_max]	Pass/fail
Segmented integral energy	Energy of segment 1 [ Ei _ min, Ei _ max](i＝1,...,n)	Pass/fail

Wherein, Peak _ low and Peak _ high are a main wavelength low threshold and a main wavelength high threshold respectively; wave _ min and Wave _ max are respectively a half-Wave width low threshold and a half-Wave width high threshold; strength _ min and Strength _ max are respectively a Strength low value threshold and a Strength high value threshold; ei _ min and Ei _ max are energy-integrated low and high values, respectively.

The range of each index may be set manually or automatically generated by analyzing spectral image data of a product. The automatic generation refers to that a system analyzes the spectrum information of a certain number of qualified products to obtain a spectrum data space 1; analyzing the spectrum information of a certain number of unqualified products to obtain a spectrum data space 2; and calculating a partition boundary between the spectral data space 1 and the spectral data space 2, namely a qualified detection threshold and a unqualified detection threshold. In addition to the pass/fail determination methods shown in table 1, the degree of fail can be subdivided into a plurality of grades, and the pass/fail of the "single detection conclusion" in table 1 can be subdivided into pass/slight fail/general fail/severe fail.

For a product containing multiple webs, the initial position of the first web, the width of each web, the distance between webs and the like can be manually specified, and the system performs spectrum detection according to specified parameters. Or the system automatically analyzes and compares the spectrum of the effective part and the spectrum of the interval part to obtain the data of the first initial position, the width of each web, the distance between webs and the like.

In addition, the spectral data can be converted into CIE XYZ value and CIE L^*a^*b^*Value, CIE h_abAnd

and (4) performing qualified/unqualified detection in a relevant color space (coordinate system) according to a qualified data range generated by automatic learning or a qualified data range designated manually.

(II) multimodal Spectroscopy

A plurality of single-peak spectrums can be obtained through decoupling, each single-peak spectrum is analyzed and detected by referring to the single-peak spectrum method, parameter indexes such as energy integration, central wavelength, dominant wavelength intensity and the like of each single-peak spectrum are analyzed and compared, and comprehensive analysis is carried out.

In addition, in the process of detecting the reflection image, whether the reflection image is qualified or not can be detected through indexes such as the color high-low value range of the reflection image, the high-low value image template, the number of the patterns, the integrity degree of the patterns, the similarity degree of the patterns and the like. The range of each index may be set manually or automatically generated by analyzing spectral image data of a qualified product.

In the process of detecting the transmission image, whether the reflection image is qualified or not can be detected through indexes such as the color high-low value range of the transmission image, the high-low value image template, the number of the patterns, the integrity degree of the patterns, the similarity degree of the patterns and the like. The range of each index may be set manually or automatically generated by analyzing spectral image data of a qualified product.

The image analysis master station collects the detection information of the spectrum acquisition and processing subsystem, the reflection image acquisition and processing subsystem and the transmission image acquisition and processing subsystem, converts the detection information into consistent image resolution, aligns the image positions and aligns the image positions with the physical positions to obtain the detection result information of the product. The integrated defect value of a certain image position (i, j) is the fusion of a plurality of image defect values, as shown in formula (1).

Wherein i represents a width direction when the image data is acquired, j represents a length direction of the acquired image data, and w_nIn the range of [0,1]The n-th oriented image data defect weight coefficient at each position is expressed, and the range of Blobn (i, j) is [0,255%]And indicates the n-th oriented image data defect value at each position, where 0 indicates no defect and 255 indicates the most serious defect. TotolBlob (i, j) represents the integrated defect value at each location.

Specifically, the transverse resolution of each defect point is bx mm/pixel by calculating the scaling of the imaging parameter and the defect map compared with the original image, and then the transverse position corresponding to the ith point is i × bx mm. And calculating the longitudinal resolution of each defect point to be by mm/pixel according to the drawing period in the advancing direction, the advancing speed and the scaling of the defect map compared with the original image, wherein the transverse position corresponding to the jth point is j x bx mm. When one or more detection items are unqualified, the position (i, j) is judged to be unqualified.

Further, it is also possible to match the image position with the dividing means based on the image data and the horizontal and vertical division specification parameters of the product, to correspond i (widthwise position) to the dividing means such as the width and the root, and to correspond j (traveling position) to the dividing means such as the segment. When the analysis master station judges that a product at a certain position is unqualified, relevant information is displayed and stored; or informing the quality marking subsystem to execute defect marking; or the quality information is transmitted to a product processing system of the post-process, and the defective product is processed subsequently.

The technical scheme of the invention is described in detail in combination with the attached drawings, and the technical scheme of the invention can automatically select a proper film quality detection mode for a user, thereby improving the reliability of a film quality detection result and improving the efficiency and quality of film detection.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A film quality detection method is used for a film quality detection system, and is characterized by comprising the following steps:

selecting a target imaging mode from a plurality of preset imaging modes according to a received detection command, wherein the detection command comprises a periodic acquisition command of a film to be detected or a command for acquiring data of the film to be detected according to a trigger signal;

acquiring image data of a plurality of positions of the film to be detected by using the target imaging mode;

determining whether the quality of the film to be detected at each position is qualified or not according to the attribute, the set shape, the set range value and the threshold range after data conversion of the image data at each position in the plurality of positions so as to determine whether the quality of the film to be detected is qualified or not;

wherein the plurality of imaging modalities includes:

in the first imaging mode, reflected light or transmitted light of a narrow-band region of the film to be detected enters a light splitting component of the film quality detection system after being focused by a lens, and lights with different wavelengths after being split are spatially separated and projected to one or a group of area array grayscale cameras of the film quality detection system;

in the second imaging mode, the specular reflection light of a narrow-band area of the film to be detected enters one or a group of gray scale or color linear array cameras of the film quality detection system after being focused by a lens;

in a third imaging mode, after being focused by a lens, diffuse reflection light of a narrow-band area of the film to be detected enters one or a group of gray scale or color linear array cameras of the film quality detection system;

in a fourth imaging mode, transmitted light of a narrow-band region of the film to be detected enters one or a group of gray scale or color linear array cameras of the film quality detection system after being focused by a lens;

and the multiple imaging modes are used for respectively acquiring different optical characteristic images of the film to be detected.

2. The film quality detection method according to claim 1, wherein the acquiring image data of a plurality of positions of the film to be detected by using the target imaging mode specifically comprises:

acquiring image data of the whole breadth width of the film to be detected for multiple times by using an image data acquisition device corresponding to the target imaging mode so as to acquire full-width image data of the film to be detected; or

And using an image data collector corresponding to the target imaging mode to collect image data of partial breadth width of the film to be detected for multiple times, wherein the image data collector is static in the width direction or moves back and forth.

3. The method according to claim 2, wherein the image data corresponding to different imaging modes have different attributes, wherein the first imaging mode is a spectral imaging mode, the second imaging mode and the third imaging mode are a reflective imaging mode, and the fourth imaging mode is a transmissive imaging mode, and the attributes of the image data corresponding to the spectral imaging mode include:

a dominant wavelength, a half-wave width, a peak intensity, an energy integral, a dominant wavelength of a certain wavelength interval, a half-wave width of a certain wavelength interval, a peak value of a certain wavelength interval of the image dataIntensity, energy integral of a certain wavelength interval, CIE XYZ value, CIE L^*a^*b^*Value, CIE h_abAnd C^* _abValue, CIE is the color system, CIE XYZ, CIE L^*a^*b^*、CIE h_ab、C^* _abA color space different for said color system, an

The attribute of the image data corresponding to the reflection imaging mode and the transmission imaging mode comprises at least one of the following or the combination thereof:

the image data comprises a high-low value range of image data color, a high-low value image data template, the number of patterns, the integrity degree of the patterns and the similarity degree of the patterns.

4. The method for detecting the quality of the thin film according to claim 3, wherein the step of determining whether the quality of the thin film to be detected at each position is qualified comprises the following steps:

according to the attribute of the image data of each position, calculating a comprehensive defect value of each position through a preset defect value calculation formula so as to determine whether the quality of the film to be detected at each position is qualified or not according to the comprehensive defect value of each position, wherein the preset defect value calculation formula is as follows:

wherein i represents a width direction in which the image data is acquired, j represents a length direction in which the image data is acquired, and w_nIn the range of [0,1]Indicating the n-th oriented image data defect weight coefficient at each position, wherein the range of Blobn (i, j) is [0, 255%]Indicating the n-th oriented image data defect value at said each location, TotolBlob (i, j) indicating said integrated defect value at said each location.

5. The film quality inspection method according to claim 4, further comprising, before said determining whether the quality of the film to be inspected at each position is acceptable:

determining a qualified data space and an unqualified data space of the image data according to the attribute of the image data of each position in the plurality of positions;

setting a quality judging condition according to a boundary of the qualified data space and the unqualified data space, so as to determine whether the quality of the film to be detected is qualified or not according to the quality judging condition; and

and determining Blobn (i, j) of the image data according to the attribute of the image data, the qualified data space and the unqualified data space.

6. A film quality inspection system, comprising:

the imaging mode selection unit is used for selecting a target imaging mode from a plurality of preset imaging modes according to a received detection command, wherein the detection command comprises a periodic acquisition command of a film to be detected or a command for acquiring data of the film to be detected according to a trigger signal;

the image data acquisition unit acquires image data of a plurality of positions of the film to be detected in a target imaging mode;

the quality judging unit is used for determining whether the quality of the film to be detected at each position is qualified or not according to the attribute, the set shape, the set range value and the threshold range after data conversion of the image data at each position in the plurality of positions so as to determine whether the quality of the film to be detected is qualified or not;

wherein the plurality of imaging modalities includes:

7. The film quality inspection system of claim 6, wherein the image data acquisition unit comprises:

the first acquisition unit is used for acquiring the image data of the whole breadth width of the film to be detected for multiple times by using an image data acquisition device corresponding to the target imaging mode so as to acquire the full-width image data of the film to be detected; and/or

And the second acquisition unit acquires image data of partial breadth width of the film to be detected for multiple times by using an image data acquisition unit corresponding to the target imaging mode, wherein the image data acquisition unit is static in the width direction or moves back and forth.

8. The film quality inspection system of claim 7, wherein the image data for different imaging modalities have different attributes, wherein the first imaging modality is a spectral imaging modality, the second imaging modality and the third imaging modality are reflective imaging modalities, and the fourth imaging modality is a transmissive imaging modality,

the attributes of the image data corresponding to the spectral imaging mode include:

dominant wavelength, half wave width, peak intensity, energy integral, certain wavelength region of the image dataDominant wavelength between, half wave width of a certain wavelength interval, peak intensity of a certain wavelength interval, energy integral of a certain wavelength interval, CIE XYZ value, CIE L^*a^*b^*Value, CIE h_abAnd C^* _abValue, CIE is the color system, CIE XYZ, CIE L^*a^*b^*、CIE h_ab、C^* _abA color space different for said color system, an

9. The film quality inspection system of claim 8, wherein the quality determination unit is specifically configured to:

10. The film quality inspection system of claim 9, further comprising:

before determining whether the quality of the film to be detected at each position is qualified, a judging condition setting unit determines a qualified data space and an unqualified data space of the image data according to the attribute of the image data at each position in the plurality of positions, and sets a quality judging condition according to a boundary of the qualified data space and the unqualified data space, so as to determine whether the quality of the film to be detected is qualified according to the quality judging condition; and

and a defect value determining unit for determining Blobn (i, j) of the image data according to the attribute of the image data, the qualified data space and the unqualified data space.