CN113176274A - Automatic focusing method, device and system for detecting defects of display panel - Google Patents
Automatic focusing method, device and system for detecting defects of display panel Download PDFInfo
- Publication number
- CN113176274A CN113176274A CN202110295309.8A CN202110295309A CN113176274A CN 113176274 A CN113176274 A CN 113176274A CN 202110295309 A CN202110295309 A CN 202110295309A CN 113176274 A CN113176274 A CN 113176274A
- Authority
- CN
- China
- Prior art keywords
- camera
- image
- display panel
- focusing
- images
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 230000007547 defect Effects 0.000 title claims abstract description 53
- 238000000034 method Methods 0.000 title claims abstract description 41
- 238000011156 evaluation Methods 0.000 claims abstract description 89
- 238000006073 displacement reaction Methods 0.000 claims abstract description 43
- 238000001514 detection method Methods 0.000 claims abstract description 20
- 241001156002 Anthonomus pomorum Species 0.000 claims description 5
- 238000012544 monitoring process Methods 0.000 claims description 4
- 238000004590 computer program Methods 0.000 claims description 3
- 238000012634 optical imaging Methods 0.000 abstract description 35
- 230000005484 gravity Effects 0.000 description 14
- 238000005516 engineering process Methods 0.000 description 13
- 230000003287 optical effect Effects 0.000 description 6
- 230000000694 effects Effects 0.000 description 3
- 239000010408 film Substances 0.000 description 3
- 238000003384 imaging method Methods 0.000 description 3
- 238000010586 diagram Methods 0.000 description 2
- 230000033001 locomotion Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 230000005540 biological transmission Effects 0.000 description 1
- 238000000265 homogenisation Methods 0.000 description 1
- 238000007689 inspection Methods 0.000 description 1
- 239000004973 liquid crystal related substance Substances 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 239000010409 thin film Substances 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/84—Systems specially adapted for particular applications
- G01N21/88—Investigating the presence of flaws or contamination
- G01N21/95—Investigating the presence of flaws or contamination characterised by the material or shape of the object to be examined
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/84—Systems specially adapted for particular applications
- G01N21/88—Investigating the presence of flaws or contamination
- G01N21/8851—Scan or image signal processing specially adapted therefor, e.g. for scan signal adjustment, for detecting different kinds of defects, for compensating for structures, markings, edges
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/84—Systems specially adapted for particular applications
- G01N21/88—Investigating the presence of flaws or contamination
- G01N21/8851—Scan or image signal processing specially adapted therefor, e.g. for scan signal adjustment, for detecting different kinds of defects, for compensating for structures, markings, edges
- G01N2021/8887—Scan or image signal processing specially adapted therefor, e.g. for scan signal adjustment, for detecting different kinds of defects, for compensating for structures, markings, edges based on image processing techniques
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/84—Systems specially adapted for particular applications
- G01N21/88—Investigating the presence of flaws or contamination
- G01N21/95—Investigating the presence of flaws or contamination characterised by the material or shape of the object to be examined
- G01N2021/9513—Liquid crystal panels
Landscapes
- Chemical & Material Sciences (AREA)
- Biochemistry (AREA)
- Pathology (AREA)
- Physics & Mathematics (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Immunology (AREA)
- Analytical Chemistry (AREA)
- General Physics & Mathematics (AREA)
- General Health & Medical Sciences (AREA)
- Engineering & Computer Science (AREA)
- Computer Vision & Pattern Recognition (AREA)
- Signal Processing (AREA)
- Automatic Focus Adjustment (AREA)
- Studio Devices (AREA)
Abstract
The invention provides an automatic focusing method, device and system for detecting defects of a display panel, and relates to the technical field of defect detection of display panels. The invention discloses an automatic focusing method for detecting defects of a display panel, which comprises the following steps: acquiring an image of the display panel in real time in the pre-positioning area through a camera; adjusting the position of the camera according to a set condition so that the camera collects a plurality of images; determining an image with the highest definition evaluation score in a plurality of images through an evaluation algorithm; determining a corresponding laser displacement sensor value according to the image with the highest definition evaluation score; and adjusting the position of the camera in real time by taking the numerical value of the laser displacement sensor as a focusing reference value. According to the technical scheme, the image definition is evaluated through the evaluation algorithm, the situation that misjudgment possibly occurs in a manual focusing mode is reduced, the optical imaging system is always located at the focusing position, and the optical imaging system is enabled to clearly acquire images with high quality.
Description
Technical Field
The invention relates to the technical field of display panel defect detection, in particular to an automatic focusing method, device and system for display panel defect detection.
Background
Display panels are important raw materials for producing TFT-LCD (Thin film transistor liquid crystal display), and during the production process, due to various reasons, various defects of different types, including various defects on circuit boards, display panels and filters, are inevitably generated by parts. The defects not only affect the performance of the product and cause huge economic loss to manufacturers, but also even endanger the personal safety of users in severe cases.
The size of the display panel is developed from 300mm × 400mm in the first generation line to 2850mm × 3050mm in the tenth generation line, and as the size of the display panel is larger and larger, the detection accuracy is higher and higher, and the requirements on the AOI (automatic optical inspection) technology for surface defects are higher and higher. Due to the requirement of high precision, an optical imaging system with high magnification is often adopted, for example, 3.5 times, 5 times and other magnifications, and the flange distance from the lens of the optical imaging system with high magnification to the camera is very long, which causes the depth of field to be very small, usually +/-10 μm, as small as +/-5 μm. In addition, besides a small depth of field, the display panel on the air floating platform is warped to a certain extent, and the imaging definition is affected.
Disclosure of Invention
The problem solved by the invention is how to enable an optical imaging system to acquire images clearly with high quality.
In order to solve the above problems, the present invention provides an auto-focusing method for detecting defects of a display panel, comprising: acquiring an image of the display panel in real time in the pre-positioning area through a camera; adjusting the position of the camera according to a set condition so that the camera collects a plurality of images; determining an image with the highest definition evaluation score in a plurality of images through an evaluation algorithm; determining a corresponding laser displacement sensor value according to the image with the highest definition evaluation score; and adjusting the position of the camera in real time by taking the numerical value of the laser displacement sensor as a focusing reference value.
According to the automatic focusing method for detecting the defects of the display panel, the image definition is evaluated through the evaluation algorithm, the situation that misjudgment possibly occurs in a manual focusing mode is reduced, the optical imaging system is always located at the focusing position through the automatic focusing technology, and the optical imaging system is ensured to be capable of clearly acquiring images with high quality.
Optionally, the acquiring, by the camera, the image of the display panel in real time in the predetermined position area includes: and focusing and pre-positioning the camera, so that the camera moves to the pre-positioning area to acquire the image in real time.
According to the automatic focusing method for detecting the defects of the display panel, the camera is focused and pre-positioned, so that the camera moves to the pre-positioned area to acquire the image in real time, the camera acquires the image in the area near the optimal focusing position, the optical imaging system is always positioned at the focusing position through the automatic focusing technology, and the optical imaging system can acquire the image clearly with high quality.
Optionally, the adjusting the position of the camera according to the setting condition so that the camera captures a plurality of images includes: and driving a Z-axis motor according to set conditions so that the camera moves in a stroke containing the optimal focusing position to acquire the image, and recording a Z-axis position value corresponding to the image and the numerical value of the laser displacement sensor as recording data.
According to the automatic focusing method for detecting the defects of the display panel, the motor is driven according to the set conditions, so that the motor drives the camera to collect images near the optimal in-focus position, and further, the optical imaging system can be always positioned at the in-focus position through the automatic focusing technology, and the optical imaging system can be ensured to clearly collect the images with high quality; and meanwhile, after the image with the highest definition evaluation score is subsequently determined, the laser displacement sensor value corresponding to the image with the highest definition evaluation score can be determined according to the recorded data.
Optionally, the driving the Z-axis motor according to the set condition includes: and any two of the walking distance, the stroke and the acquisition times are combined to determine the acquisition frequency of the camera, and the operating frequency of the Z-axis motor is determined according to the acquisition frequency.
The automatic focusing method for detecting the defects of the display panel determines the acquisition frequency of the camera by combining any two of the walking distance, the stroke and the acquisition times, determines the operating frequency of the Z-axis motor according to the acquisition frequency, enables the motor to drive the camera to acquire images near the optimal in-focus position, and further enables the optical imaging system to be always positioned at the in-focus position through the automatic focusing technology, thereby ensuring that the optical imaging system can acquire the images clearly with high quality.
Optionally, the determining, by an evaluation algorithm, an image with a highest sharpness evaluation score in the plurality of images includes: and determining the image with the highest definition evaluation score by any one evaluation algorithm of a variance method, a Laplace energy evaluation method, an energy gradient evaluation method, a Brenner function evaluation method and a Tenegrad function evaluation method.
According to the automatic focusing method for detecting the defects of the display panel, disclosed by the invention, the image definition is evaluated through a plurality of definition evaluation algorithms, the algorithm adaptability is enhanced, the image definition judgment accuracy is improved, and therefore the optimal focusing position is accurately determined.
Optionally, the determining a corresponding laser displacement sensor value through the image with the highest sharpness evaluation score includes: and determining the laser displacement sensor value corresponding to the image with the highest definition evaluation score according to the recorded data.
According to the automatic focusing method for detecting the defects of the display panel, the laser displacement sensor value corresponding to the image with the highest definition evaluation score is determined according to the recorded data, so that the optimal focusing position is determined, and the optical imaging system can acquire the image clearly with high quality.
Optionally, the adjusting the position of the camera in real time by using the laser displacement sensor value as a focusing reference value includes: and adjusting a Z axis through the Z axis motor according to the focusing reference value so as to drive the camera to move.
According to the automatic focusing method for detecting the defects of the display panel, the Z axis is adjusted through the Z axis motor according to the focusing reference value so as to drive the camera to move, so that the camera moves to the optimal focusing position, and the optical imaging system is ensured to be capable of clearly acquiring images with high quality.
The present invention also provides an auto-focusing apparatus for detecting defects of a display panel, comprising: the acquisition module is used for acquiring images of the display panel in real time in the preset position area through the camera; the adjusting module is used for adjusting the position of the camera according to a set condition so as to enable the camera to collect a plurality of images; the evaluation module is used for determining the image with the highest definition evaluation score in the plurality of images through an evaluation algorithm; the sensor module is used for determining a corresponding laser displacement sensor value according to the image with the highest definition evaluation score; and the focusing module is used for adjusting the position of the camera in real time by taking the numerical value of the laser displacement sensor as a focusing reference value. The auto-focusing device for detecting the defect of the display panel and the auto-focusing method for detecting the defect of the display panel have the same advantages compared with the prior art, and are not repeated herein.
The invention also provides an automatic focusing system for detecting the defects of the display panel, which comprises a voice coil motor, a first distance measuring sensor, a position encoder and a controller, wherein the voice coil motor, the first distance measuring sensor and the position encoder are respectively and electrically connected with the controller, the distance measuring sensor is used for monitoring the spacing distance between a camera and the panel to be detected and feeding back the spacing distance to the controller, the position encoder is used for monitoring the position information of the camera and feeding back the position information to the controller, the voice coil motor is used for driving the camera to move, and the controller is used for realizing the automatic focusing method for detecting the defects of the display panel. The auto-focusing system for detecting the defect of the display panel and the auto-focusing method for detecting the defect of the display panel have the same advantages compared with the prior art, and are not repeated herein.
The present invention also provides a computer-readable storage medium storing a computer program which, when read and executed by a processor, implements the auto-focusing method for display panel defect detection as described above. The advantages of the computer-readable storage medium and the above-mentioned auto-focusing method for detecting defects of a display panel are the same as those of the prior art, and are not described herein again.
Drawings
FIG. 1 is a flowchart of an auto-focusing method for detecting defects of a display panel according to an embodiment of the present invention;
FIG. 2 is a diagram illustrating an auto-focusing method according to an embodiment of the present invention;
FIG. 3 is a block diagram of an auto focus system for detecting defects of a display panel according to an embodiment of the present invention;
FIG. 4 is a bottom view of an auto focus system for display panel defect detection according to an embodiment of the present invention;
FIG. 5 is a side view of an auto focus system for defect detection of a display panel according to an embodiment of the present invention.
Description of reference numerals:
the detection device comprises a voice coil motor 1, a first distance measuring sensor 2, a position encoder 3, a bottom plate 4, a movable plate 5, a gravity compensation mechanism 6, a guide mechanism 7, a guide movable part 71, a guide fixed part 72, a camera 8 and a panel to be detected 9.
Detailed Description
In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below.
As shown in fig. 1, an embodiment of the present invention provides an auto-focusing method for detecting defects of a display panel, including: acquiring an image of the display panel in real time in the pre-positioning area through a camera; adjusting the position of the camera according to a set condition so that the camera collects a plurality of images; determining an image with the highest definition evaluation score in a plurality of images through an evaluation algorithm; determining a corresponding laser displacement sensor value according to the image with the highest definition evaluation score; and adjusting the position of the camera in real time by taking the numerical value of the laser displacement sensor as a focusing reference value.
Specifically, in the present embodiment, the auto-focusing method for detecting defects of a display panel includes: acquiring an image of the display panel in real time through a camera in a pre-positioning area, wherein the pre-positioning area refers to an area near an optimal in-focus position, namely acquiring the image near the optimal in-focus position; adjusting the position of a camera according to a set condition to enable the camera to collect a plurality of images, so that the definition of the plurality of images can be evaluated, wherein the set condition refers to setting how far the camera collects the images at intervals, namely determining the collection frequency of the camera, so as to determine the operating frequency of a Z-axis motor; determining an image with the highest definition evaluation score in the plurality of images through an evaluation algorithm; determining the corresponding laser displacement sensor value through the image with the highest definition evaluation score, so that the position of the image which is the clearest can be determined according to the value; the position of the camera is adjusted in real time by taking the numerical value of the laser displacement sensor as a focusing reference value, and the camera is moved to the position where the image is most clear (namely the best focusing position), so that automatic focusing is realized. According to the method and the device, the image definition is evaluated through the evaluation algorithm, the situation that misjudgment possibly occurs in a manual focusing mode is reduced, the optical imaging system is always located at the focusing position through the automatic focusing technology, and the optical imaging system is ensured to be capable of clearly acquiring images with high quality.
The optical imaging system generally comprises a bottom plate, a voice coil motor, a linear guide unit moving part, a linear guide unit fixing part, a gravity compensation unit, a movable plate, an optical detection unit, a distance measurement sensor, a position encoder and a flat plate, wherein the voice coil motor, namely a stator of a Z-axis motor, is fixedly arranged on the bottom plate, and one end of a rotor of the voice coil motor is connected with the movable plate; the linear guide unit guide rail is fixedly arranged on the bottom plate, and the guide moving part is fixedly connected with the movable plate; one side of the gravity compensation unit is fixedly connected with the bottom plate, the other side of the gravity compensation unit is connected with the movable plate, and the gravity compensation unit achieves the purpose of gravity compensation of the whole device by providing a constant force which is opposite to the gravity direction of the device and approximately equal to the gravity direction of the device; the optical detection unit, namely a camera, is fixedly arranged on the movable plate and moves along with the movable plate; the distance measuring sensor, namely a laser displacement sensor, is arranged on the movable plate/optical detection unit and is used for detecting the distance from the optical lens to the surface of the flat plate; the position encoder is arranged on the movable plate and used for feeding back the walking distance of the optical detection unit to the voice coil motor in real time.
In the embodiment, the image definition is evaluated through an evaluation algorithm, the situation that misjudgment possibly occurs in a manual focusing mode is reduced, the optical imaging system is always located at a focusing position through an automatic focusing technology, and the optical imaging system is ensured to be capable of clearly acquiring images with high quality.
Optionally, the acquiring, by the camera, the image of the display panel in real time in the predetermined position area includes: and focusing and pre-positioning the camera, so that the camera moves to the pre-positioning area to acquire the image in real time.
Specifically, in the present embodiment, acquiring an image of the display panel in real time by the camera at the predetermined position area includes: and focusing and pre-positioning the camera, so that the camera moves to a pre-positioning area to acquire an image in real time. When focusing is performed for prepositioning, a manual mode or an automatic mode can be adopted, wherein the manual mode is that an operator identifies definition through human eyes to manually adjust the position of the camera, and the automatic mode is that the position of the camera is automatically and preliminarily adjusted through image definition pre-comparison. In the embodiment, the camera is focused and pre-positioned, so that the camera moves to the pre-positioned area to acquire the image in real time, the camera acquires the image in the area near the optimal focusing position, and then the optical imaging system can be always positioned at the focusing position through the automatic focusing technology, so that the optical imaging system can acquire the image clearly with high quality.
In the embodiment, the camera is focused and pre-positioned, so that the camera moves to the pre-positioned area to acquire an image in real time, the camera acquires the image in the area near the optimal in-focus position, and then the optical imaging system can be always positioned at the in-focus position through the automatic focusing technology, so that the optical imaging system can acquire the image clearly with high quality.
Optionally, the adjusting the position of the camera according to the setting condition so that the camera captures a plurality of images includes: and driving a Z-axis motor according to set conditions so that the camera moves in a stroke containing the optimal focusing position to acquire the image, and recording a Z-axis position value corresponding to the image and the numerical value of the laser displacement sensor as recording data.
Specifically, in this embodiment, adjusting the position of the camera according to the setting condition so that the camera captures a plurality of images includes: and driving a Z-axis motor according to set conditions so that the camera moves in a stroke containing the optimal focusing position to acquire an image, and recording a Z-axis position value corresponding to the image and a laser displacement sensor value as recording data. Referring to fig. 2, the arrow direction at the upper left corner is a Z-axis direction, the camera and the laser displacement sensor move up and down along the Z-axis, the laser displacement sensor is mounted on the camera and used for detecting the distance from the lens to the surface of the display panel, the layer a0 is the layer with the highest definition, other virtual layers such as Am and An layers are all layers with lower definition, and the focusing pre-positioning in step 2 means that the focusing position of the camera is close to the layer a0 (for example, any plane within ± 0.5mm of the layer a 0) through the Z-axis movement; the motor is driven according to the set conditions, so that the motor drives the camera to acquire images near the optimal in-focus position, and the optical imaging system can be always positioned at the in-focus position through the automatic focusing technology, and the optical imaging system can acquire the images clearly with high quality; and meanwhile, after the image with the highest definition evaluation score is subsequently determined, the laser displacement sensor value corresponding to the image with the highest definition evaluation score can be determined according to the recorded data.
In the embodiment, the motor is driven according to the set conditions, so that the motor drives the camera to collect images near the optimal in-focus position, and further, the optical imaging system can be always positioned at the in-focus position through the automatic focusing technology, and the optical imaging system can be ensured to collect the images clearly with high quality; and meanwhile, after the image with the highest definition evaluation score is subsequently determined, the laser displacement sensor value corresponding to the image with the highest definition evaluation score can be determined according to the recorded data.
Optionally, the driving the Z-axis motor according to the set condition includes: and any two of the walking distance, the stroke and the acquisition times are combined to determine the acquisition frequency of the camera, and the operating frequency of the Z-axis motor is determined according to the acquisition frequency.
Specifically, in the present embodiment, driving the Z-axis motor according to the set condition includes: and any two combinations of the walking distance, the stroke and the acquisition times are used as set conditions to determine the acquisition frequency of the camera, and the operating frequency of the Z-axis motor is determined according to the acquisition frequency.
Referring to fig. 2, for example, a stroke and a collection frequency are set, a stroke 1mm (a walking direction is ± 0.5mm) is set, the collection frequency is 100 times, where a collection interval is 1000/100 μm/time, and a walking interval and a stroke or a combination of a walking interval and a collection frequency are also similar, so as to set how far the camera collects images, that is, determine a collection frequency of the camera, thereby determining an operating frequency of a Z-axis motor, so that the motor drives the camera to move on a Z-axis, and the camera performs equidistant image collection according to the collection interval, as above, one image can be collected every 10 μm, and a Z-axis position corresponding to each image and a position of the laser displacement sensor are recorded. The acquisition frequency of the camera is determined by combining any two of the walking distance, the stroke and the acquisition times, and the running frequency of the Z-axis motor is determined according to the acquisition frequency, so that the motor drives the camera to acquire images near the optimal in-focus position, and then the optical imaging system can be always positioned at the in-focus position through the automatic focusing technology, and the optical imaging system can be ensured to clearly acquire the images with high quality.
In this embodiment, the acquisition frequency of the camera is determined by combining any two of the walking distance, the travel and the acquisition times, and the operating frequency of the Z-axis motor is determined according to the acquisition frequency, so that the motor drives the camera to acquire an image near the optimal in-focus position, and further the optical imaging system can be always located at the in-focus position through the automatic focusing technology, thereby ensuring that the optical imaging system can clearly acquire the image with high quality.
Optionally, the determining, by an evaluation algorithm, an image with a highest sharpness evaluation score in the plurality of images includes: and determining the image with the highest definition evaluation score by any one evaluation algorithm of a variance method, a Laplace energy evaluation method, an energy gradient evaluation method, a Brenner function evaluation method and a Tenegrad function evaluation method.
Specifically, in this embodiment, the determining, by the evaluation algorithm, the image with the highest sharpness evaluation score among the plurality of images includes: and determining the image with the highest definition evaluation score by any one evaluation algorithm of a variance method, a Laplace energy evaluation method, an energy gradient evaluation method, a Brenner function evaluation method and a Tenegrad function evaluation method. The image definition is evaluated through various definition evaluation algorithms, algorithm adaptability is enhanced, and image definition judgment accuracy is improved, so that the optimal focusing position is accurately determined.
Among them, since a sharply focused image has a larger gray difference than a blurred image, a variance function can be used as an evaluation function. The image with clear focus has larger gray difference between its data compared with the image with fuzzy focus, i.e. the variance of the gray data of the image is larger, and the image definition can be measured by the variance of the gray data of the image, and the larger the variance is, the better the definition is.
The method comprises the steps of performing template convolution on an image by utilizing a Laplacian operator to obtain a high-frequency component of the image, then summing the high-frequency components of the image, and using the sum of the high-frequency components as a definition evaluation standard of the image.
The energy gradient function takes the square sum of the difference between the gray values of the adjacent pixels in the x direction and the y direction as the gradient value of each pixel point, and the gradient values of all the pixels are accumulated to be used as a definition evaluation function value.
Among them, the Brenner gradient function is the simplest gradient evaluation function, and the sharpness is evaluated by calculating the square of the gray difference between two adjacent pixels.
The Tenegrad function is a commonly used image definition evaluation function and is a function based on gradient. In image processing, it is generally believed that the in-focus image has sharper edges and therefore larger gradient function values.
In the embodiment, the image definition is evaluated through a plurality of definition evaluation algorithms, so that the algorithm adaptability is enhanced, the image definition judgment accuracy is improved, and the optimal focusing position is accurately determined.
Optionally, the determining a corresponding laser displacement sensor value through the image with the highest sharpness evaluation score includes: and determining the laser displacement sensor value corresponding to the image with the highest definition evaluation score according to the recorded data.
Specifically, in this embodiment, determining the corresponding laser displacement sensor value from the image with the highest sharpness evaluation score includes: and determining the laser displacement sensor value corresponding to the image with the highest definition evaluation score according to the recorded data. After the image with the highest sharpness evaluation score is determined, because the Z-axis position value and the laser displacement sensor value corresponding to the image are recorded as the recording data when the camera moves to collect the image in the stroke containing the best in-focus position, the laser displacement sensor value corresponding to the image with the highest sharpness evaluation score can be determined through the recording data, which is equivalent to determining the best in-focus position of the camera.
In the embodiment, the laser displacement sensor value corresponding to the image with the highest definition evaluation score is determined according to the recorded data, so that the optimal focusing position is determined, and the optical imaging system can acquire the image clearly with high quality.
Optionally, the adjusting the position of the camera in real time by using the laser displacement sensor value as a focusing reference value includes: and adjusting a Z axis through the Z axis motor according to the focusing reference value so as to drive the camera to move.
Specifically, in this embodiment, the adjusting the position of the camera in real time by using the laser displacement sensor value as the focusing reference value includes: and adjusting a Z axis through a Z axis motor according to the focusing reference value to drive the camera to move. Namely, the camera position is adjusted according to the focusing reference value, so that the camera moves to the optimal focusing position, and the optical imaging system can clearly acquire images with high quality.
In the embodiment, the Z axis is adjusted by the Z axis motor according to the focusing reference value to drive the camera to move, so that the camera moves to the optimal focusing position, and the optical imaging system is ensured to clearly acquire images with high quality. The voice coil motor capable of moving at high frequency can be adopted to achieve the effect of focusing in real time in the acquisition process.
Another embodiment of the present invention provides an auto-focusing apparatus for detecting defects of a display panel, including: the acquisition module is used for acquiring images of the display panel in real time in the preset position area through the camera; the adjusting module is used for adjusting the position of the camera according to a set condition so as to enable the camera to collect a plurality of images; the evaluation module is used for determining the image with the highest definition evaluation score in the plurality of images through an evaluation algorithm; the sensor module is used for determining a corresponding laser displacement sensor value according to the image with the highest definition evaluation score; and the focusing module is used for adjusting the position of the camera in real time by taking the numerical value of the laser displacement sensor as a focusing reference value.
Another embodiment of the present invention provides an auto-focusing system for panel defect detection, and with reference to fig. 3 to 5, the auto-focusing system includes a voice coil motor 1, a first distance measuring sensor 2, a position encoder 3 and a controller, the voice coil motor 1, the first distance measuring sensor 2 and the position encoder 3 are respectively electrically connected to the controller, the distance measuring sensor is configured to monitor a distance between a camera 8 and a panel 9 to be detected and feed back the distance to the controller, the position encoder 3 is configured to monitor position information of the camera 8 and feed back the position information to the controller, the voice coil motor 1 is configured to drive the camera 8 to move, and the controller is configured to implement the auto-focusing method for display panel defect detection according to the above embodiment.
Optionally, as shown in fig. 4, the auto-focusing system for detecting defects of a display panel further includes a bottom plate 4 and a movable plate 5, a stator of the voice coil motor 1 is disposed on the bottom plate 4, a mover of the voice coil motor 1 is connected to the movable plate 5, the movable plate 5 is adapted to move relative to the bottom plate 4, and the movable plate 5 is adapted to be disposed with the camera 8.
Optionally, the auto-focusing system for detecting defects of a display panel further includes a gravity compensation mechanism 6, the gravity compensation mechanism 6 is connected to the movable plate 5, and the gravity compensation mechanism 6 is configured to output a constant force opposite to the gravity direction of the camera 8.
Optionally, the auto-focusing system for detecting defects of a display panel further comprises a guiding mechanism 7, wherein the guiding mechanism 7 is used for limiting the moving direction of the movable plate 5 relative to the bottom plate 4.
Since the panel 9 to be detected is up and down fluctuated on the air floating platform, the camera 8 should move up and down along with the panel to be detected in order to ensure the imaging effect of the camera 8, in order to limit the motion track of the camera 8 relative to the bottom plate 4, a guide mechanism needs to be arranged on the bottom plate 4, and the moving direction of the movable plate 5 relative to the bottom plate 4 is limited through the guide mechanism 7 so as to limit the moving direction of the camera 8 arranged on the movable plate 5.
Optionally, the guiding mechanism 7 includes a guiding movable member 71 and a guiding fixed member 72, the guiding fixed member 72 is disposed on the bottom plate 4, the guiding movable member 71 is connected to the movable plate 5, and the guiding movable member 71 is adapted to move along an extending direction of the guiding fixed member 72 relative to the guiding fixed member 72.
The extending direction of the guide fixing member 72 is the vertical direction.
Specifically, the guide fixing member 72 is slidably connected to the guide moving member 71, and the guide moving member 71 can only move up and down by the restriction of the guide fixing member 72, so that the guide moving member 71 is connected to the movable plate 5 by disposing the guide fixing member 72 on the bottom plate 4, so that the movable direction of the movable plate 5 with respect to the bottom plate 4 is an up-down direction, thereby defining the movable direction of the camera 8 as an up-down direction.
Optionally, the guiding fixing member 72 includes two guide rails, the two guide rails are parallel and spaced apart from each other, and the gravity compensation mechanism 6 is disposed between the two guide rails.
Specifically, the gravity compensation mechanism 6 is arranged between the two guide rails, so that the compactness of the whole structure of the automatic focusing device is improved, and the size of the automatic focusing system for detecting the panel defects is convenient to reduce.
Wherein the guide rail may be an air-floating guide rail as described below.
Optionally, the guide fixing member 72 includes an air-float guide rail, an air film gap is formed between the guide moving member 71 and the air-float guide rail, and the air-float guide rail is disposed on the bottom plate 4.
Specifically, because an air film gap is formed between the guide moving member 71 and the air-floating guide rail, the friction force between the air-floating guide rail and the guide moving member 71 is low, and compared with a traditional contact type transmission mode adopting a linear guide rail, the friction and wear are reduced, and the service life is prolonged; on the other hand, the conventional linear guide has inconsistent deflection deformation at each positioning position, which results in inconsistent positioning accuracy of the movable guide when the movable guide is positioned at a short distance or a long distance, making it difficult to accurately move the camera 8 to the optimal imaging position. The air-float guide rail has the function of error homogenization, and can realize consistent positioning precision of the movable guide piece when the movable guide piece is positioned at a short distance or a long distance, thereby improving the accuracy of the focusing process of the camera 8.
Optionally, the guide movable member 71 includes an air bearing, an air film gap is formed between the air bearing and the guide fixed member 72, and the air bearing is connected to the movable plate 5. The same effects as those of the above embodiment can be achieved by this embodiment.
Another embodiment of the present invention provides a computer-readable storage medium storing a computer program, which when read and executed by a processor, implements the auto-focusing method for display panel defect detection as described above.
Although the present disclosure has been described above, the scope of the present disclosure is not limited thereto. Various changes and modifications may be effected therein by one of ordinary skill in the pertinent art without departing from the spirit and scope of the present disclosure, and these changes and modifications are intended to be within the scope of the present disclosure.
Claims (10)
1. An auto-focusing method for detecting defects of a display panel, comprising:
acquiring an image of the display panel in real time in the pre-positioning area through a camera;
adjusting the position of the camera according to a set condition so that the camera collects a plurality of images;
determining an image with the highest definition evaluation score in a plurality of images through an evaluation algorithm;
determining a corresponding laser displacement sensor value according to the image with the highest definition evaluation score;
and adjusting the position of the camera in real time by taking the numerical value of the laser displacement sensor as a focusing reference value.
2. The auto-focusing method for defect detection of a display panel according to claim 1, wherein said acquiring an image of the display panel in real time by the camera at the predetermined position area comprises:
and focusing and pre-positioning the camera, so that the camera moves to the pre-positioning area to acquire the image in real time.
3. The auto-focusing method for detecting defects of a display panel according to claim 1, wherein the adjusting the position of the camera according to the setting condition to make the camera capture a plurality of images comprises:
and driving a Z-axis motor according to set conditions so that the camera moves in a stroke containing the optimal focusing position to acquire the image, and recording a Z-axis position value corresponding to the image and the numerical value of the laser displacement sensor as recording data.
4. The auto-focusing method for defect detection of a display panel according to claim 3, wherein the driving the Z-axis motor according to the set condition comprises:
and any two of the walking distance, the stroke and the acquisition times are combined to determine the acquisition frequency of the camera, and the operating frequency of the Z-axis motor is determined according to the acquisition frequency.
5. The auto-focusing method for detecting defects of a display panel according to claim 1, wherein the determining an image with a highest sharpness evaluation score among a plurality of images by an evaluation algorithm comprises:
and determining the image with the highest definition evaluation score by any one evaluation algorithm of a variance method, a Laplace energy evaluation method, an energy gradient evaluation method, a Brenner function evaluation method and a Tenegrad function evaluation method.
6. The auto-focusing method for defect detection of a display panel according to claim 3, wherein the determining the corresponding laser displacement sensor value from the image with the highest sharpness evaluation score comprises:
and determining the laser displacement sensor value corresponding to the image with the highest definition evaluation score according to the recorded data.
7. The auto-focusing method for detecting defects of a display panel according to claim 3, wherein the adjusting the position of the camera in real time by using the laser displacement sensor value as a focusing reference value comprises:
and adjusting a Z axis through the Z axis motor according to the focusing reference value so as to drive the camera to move.
8. An auto-focus apparatus for defect detection of a display panel, comprising:
the acquisition module is used for acquiring images of the display panel in real time in the preset position area through the camera;
the adjusting module is used for adjusting the position of the camera according to a set condition so as to enable the camera to collect a plurality of images;
the evaluation module is used for determining the image with the highest definition evaluation score in the plurality of images through an evaluation algorithm;
the sensor module is used for determining a corresponding laser displacement sensor value according to the image with the highest definition evaluation score;
and the focusing module is used for adjusting the position of the camera in real time by taking the numerical value of the laser displacement sensor as a focusing reference value.
9. An automatic focusing system for detecting defects of a display panel is characterized by comprising a voice coil motor (1), a first distance measuring sensor (2), a position encoder (3) and a controller, the voice coil motor (1), the first distance measuring sensor (2) and the position encoder (3) are respectively electrically connected with the controller, the distance measuring sensor is used for monitoring the spacing distance between the camera (8) and the panel (9) to be detected and feeding back the spacing distance to the controller, the position encoder (3) is used for monitoring the position information of the camera (8) and feeding back the position information to the controller, the voice coil motor (1) is used for driving the camera (8) to move, and the controller is used for realizing the automatic focusing method for detecting the defects of the display panel according to any one of claims 1 to 7.
10. A computer-readable storage medium, characterized in that it stores a computer program which, when read and executed by a processor, implements the auto-focusing method for display panel defect detection according to any one of claims 1 to 7.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110295309.8A CN113176274A (en) | 2021-03-19 | 2021-03-19 | Automatic focusing method, device and system for detecting defects of display panel |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110295309.8A CN113176274A (en) | 2021-03-19 | 2021-03-19 | Automatic focusing method, device and system for detecting defects of display panel |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN113176274A true CN113176274A (en) | 2021-07-27 |
Family
ID=76922175
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110295309.8A Pending CN113176274A (en) | 2021-03-19 | 2021-03-19 | Automatic focusing method, device and system for detecting defects of display panel |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113176274A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115327740A (en) * | 2022-07-19 | 2022-11-11 | 信利光电股份有限公司 | Detection equipment capable of automatically adjusting object distance and detection method thereof |
| CN115514884A (en) * | 2022-08-23 | 2022-12-23 | 苏州华星光电技术有限公司 | Precise ultrahigh-speed position correction method and device |
| CN117056148A (en) * | 2023-08-30 | 2023-11-14 | 昆山迈致治具科技有限公司 | Method for detecting abnormal display of screen |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2007248616A (en) * | 2006-03-14 | 2007-09-27 | Olympus Imaging Corp | Focusing state display device for camera |
| CN106249325A (en) * | 2016-10-14 | 2016-12-21 | 北京信息科技大学 | A kind of bionical quick focus adjustment method of vision based on liquid lens |
| CN106303242A (en) * | 2016-08-18 | 2017-01-04 | 上海交通大学 | The focusing system quickly of muti-spectrum imaging and method |
| CN109557694A (en) * | 2019-01-16 | 2019-04-02 | 厦门福信光电集成有限公司 | A kind of automatic optical detection device and image-pickup method in the step electrode region of liquid crystal display |
| CN109696788A (en) * | 2019-01-08 | 2019-04-30 | 武汉精立电子技术有限公司 | A kind of fast automatic focusing method based on display panel |
| CN109752831A (en) * | 2017-11-02 | 2019-05-14 | 山东颐泽天泰医疗科技有限公司 | A kind of microscope auto focusing method, system and device that focal time is controllable |
| CN112230491A (en) * | 2020-10-30 | 2021-01-15 | 广西代达科技有限公司 | Application method of technical camera capable of automatically focusing |
-
2021
- 2021-03-19 CN CN202110295309.8A patent/CN113176274A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2007248616A (en) * | 2006-03-14 | 2007-09-27 | Olympus Imaging Corp | Focusing state display device for camera |
| CN106303242A (en) * | 2016-08-18 | 2017-01-04 | 上海交通大学 | The focusing system quickly of muti-spectrum imaging and method |
| CN106249325A (en) * | 2016-10-14 | 2016-12-21 | 北京信息科技大学 | A kind of bionical quick focus adjustment method of vision based on liquid lens |
| CN109752831A (en) * | 2017-11-02 | 2019-05-14 | 山东颐泽天泰医疗科技有限公司 | A kind of microscope auto focusing method, system and device that focal time is controllable |
| CN109696788A (en) * | 2019-01-08 | 2019-04-30 | 武汉精立电子技术有限公司 | A kind of fast automatic focusing method based on display panel |
| CN109557694A (en) * | 2019-01-16 | 2019-04-02 | 厦门福信光电集成有限公司 | A kind of automatic optical detection device and image-pickup method in the step electrode region of liquid crystal display |
| CN112230491A (en) * | 2020-10-30 | 2021-01-15 | 广西代达科技有限公司 | Application method of technical camera capable of automatically focusing |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115327740A (en) * | 2022-07-19 | 2022-11-11 | 信利光电股份有限公司 | Detection equipment capable of automatically adjusting object distance and detection method thereof |
| CN115514884A (en) * | 2022-08-23 | 2022-12-23 | 苏州华星光电技术有限公司 | Precise ultrahigh-speed position correction method and device |
| CN117056148A (en) * | 2023-08-30 | 2023-11-14 | 昆山迈致治具科技有限公司 | Method for detecting abnormal display of screen |
| CN117056148B (en) * | 2023-08-30 | 2024-02-09 | 昆山迈致治具科技有限公司 | Method for detecting abnormal display of screen |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN113176274A (en) | Automatic focusing method, device and system for detecting defects of display panel | |
| WO2018224015A1 (en) | Fully-automatic microscopic scanner | |
| CN103033919B (en) | System capable of automatically compensating and focusing in process of automatic scanning and method and application thereof | |
| CN113219622A (en) | Objective lens focusing method, device and system for panel defect detection | |
| CN112752021B (en) | Automatic focusing method of camera system and automatic focusing camera system | |
| CN109557694B (en) | Automatic optical detection device and image acquisition method for step electrode area of liquid crystal display | |
| KR20100124742A (en) | Electronic component inspecting method and apparatus used in the method | |
| CN108401153B (en) | Dual-camera module correction device and correction method thereof | |
| JP2012078164A (en) | Pattern inspection device | |
| CN113219618B (en) | Automatic focusing control method for panel detection and panel defect detection method | |
| JP2012149928A (en) | Characteristic inspection device of af lens unit and characteristic inspection method for the same, control program, readable storage medium | |
| CN210803857U (en) | Double-objective switching mechanism | |
| CN107796336B (en) | Automatic optical detector | |
| CN113176273B (en) | Automatic focusing device, method and panel defect detection system | |
| CN204065545U (en) | Based on microscopical digital slices scanning laser focusing device | |
| CN111487042A (en) | Measuring system and measuring method for parallelism and uniformity of collimated light beams | |
| CN116087222A (en) | Wafer dark field detection device and detection method | |
| JPH0949759A (en) | Objective-replacing mechanism for infrared camera | |
| CN109916335B (en) | Image measuring equipment and automatic focusing method thereof | |
| CN114354629A (en) | Detection equipment | |
| CN218416469U (en) | Bidirectional scanning large-format image acquisition device based on image splicing technology | |
| JPH07280537A (en) | Imaging type inspection method and apparatus | |
| CN113176278B (en) | Panel defect detection equipment and panel defect detection method | |
| CN217210758U (en) | Image instrument | |
| CN218481432U (en) | High-precision detection device for surface defects of optical element |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20210727 |