WO2022228379A1

WO2022228379A1 - Device for use in high-speed line-scan detection, and detection method therefor

Info

Publication number: WO2022228379A1
Application number: PCT/CN2022/088960
Authority: WO
Inventors: 谢春林; 张腾飞
Original assignee: 广东奥普特科技股份有限公司
Priority date: 2021-04-30
Filing date: 2022-04-25
Publication date: 2022-11-03
Also published as: CN113137936A

Abstract

A device for use in high-speed line-scan detection, and a detection method therefor. The device comprises a parallel light source device (1), a beam splitter (2), a backlight source (3) and a camera (4), wherein the beam splitter (2) is obliquely arranged at one end of the parallel light source device (1); and the beam splitter (2), the backlight source (3) and the camera (4) are arranged in a line. The device uses a telecentric optical path design of the parallel light source device (1), and emergent light has the characteristics of high parallelism and ultrahigh brightness, such that the amount of light passing through a lens can be increased, thereby increasing the light efficiency utilization rate, reducing the required camera acquisition and exposure time, and greatly improving the visual detection efficiency.

Description

A device applied to high-speed line scan detection and its detection method

This application claims the priority of the Chinese patent application filed on April 30, 2021 with the application number of 202110483877.0 and the invention titled "A device applied to high-speed line scan detection and its detection method", the entire contents of which are Incorporated herein by reference.

technical field

The invention belongs to the technical field of machine vision, and in particular relates to a device and a detection method applied to high-speed line scan detection.

Background technique

With the rapid development of automatic optical inspection technology, the market demand for inspection stability and inspection efficiency is getting higher and higher. During high-speed inspection, the stability of visual imaging effects and the detection speed are two important factors that affect the detection efficiency. For example, during the thermal detection of the flexible screen of a mobile phone, after the flexible screen is cut by a laser, the area next to it is melted due to the influence of the heat of the laser near the cutting line, resulting in a slight bulge. In order to evaluate the size of the bump, the camera needs to capture the flexible screen of the mobile phone and image the slightly raised heat-affected area for analysis, which requires higher stability and shooting speed of the shooting device.

In the prior art, the coaxial light source used for thermal detection of mobile phone flexible screens cannot have both the brightness and directivity of the light source at the same time. The existing coaxial light sources either have high brightness of the light source, poor directivity, and need to manually adjust the light source many times. , so that the directionality meets the shooting requirements, the operation is difficult, and the image acquisition speed is low; or the directionality is good, but the brightness of the light source is low, resulting in insufficient brightness of the light source lighting unit and unclear image acquisition.

SUMMARY OF THE INVENTION

The purpose of the present invention is to: in view of the deficiencies of the prior art, to provide a device for high-speed line scan detection and a detection method thereof, which have the characteristics of high brightness and good light directionality, and can greatly increase the amount of light entering the lens, Increase light utilization, shorten exposure time, and improve the efficiency of visual inspection.

In order to achieve the above object, the present invention adopts the following technical solutions:

A device applied to high-speed line scan detection, comprising a parallel light source device, a beam splitter, a backlight source and a camera, the beam splitter is inclined at one end of the parallel light source device, the beam splitter, the backlight source and the The cameras are arranged in a line. The telecentric optical path design is adopted, which makes the output light have high parallelism, so that the light flux of the lens is more, and the exposure time required for camera acquisition is reduced. Compared with ordinary coaxial light, the exposure can be reduced by 13 times, thereby greatly improving the visual inspection efficiency. .

Further, further, the parallel light source device includes a fixed body and an optical fiber point light source disposed in the fixed body. This structural design effectively enhances the structural firmness of the entire device.

Further, the fixing body is used to make the divergence angle of the light ≤ 1°. It ensures that the light output by the light source remains parallel and has a high coaxiality, increases the amount of light passing through the lens, and reduces the required exposure time for camera acquisition. Compared with ordinary coaxial light, the exposure can be reduced by 13 times, thereby greatly improving the visual inspection efficiency.

Further, the fixing body includes a first base body, a second base body and a third base body, one end of the first base body is provided with a first connection port, and one end of the third base body is provided with a corresponding first connection port The two ends of the second base are respectively connected to the first connection port and the second connection port, and the third base extends outward along the light exit direction to form expansion ports. This structural design makes the divergence angle of the light ≤ 1°, which improves the utilization rate of the light source, so that the light can be guaranteed to propagate in the same direction during the transmission process. The reflection effect can reduce the loss of light in the transmission process and improve the brightness of the light spot.

Further, a heat dissipation device is built in the first base body, and the heat dissipation device is used for heat dissipation. This structural design effectively prolongs the service life of the parallel light source device, and avoids the occurrence of equipment failure due to excessive heat generated by the light source during operation.

Further, the backlight source is used to increase the backlight amount of the product to be inspected. The purpose of adding the backlight is to assist the camera to photograph the outer contour of the product to be inspected, so as to facilitate the camera to locate and capture the product to be inspected.

Further, the distance between the upper end surface of the backlight source and the lower end surface of the product to be detected is 19.5 mm˜20.5 mm. With this structural design, the light flux of the camera lens is large, and the quality of the contour image of the product to be detected captured by the camera is improved.

Further, the distance between the lower end face of the spectroscope and the upper end face of the product to be detected is 9.5 mm˜10.5 mm. With this structural design, the light flux of the camera lens is large, and the quality of the contour image of the product to be detected captured by the camera is improved.

Further, the distance between the end face of the camera lens and the upper end face of the product to be inspected is 105mm˜145mm. With this structural design, the light flux of the camera lens is large, and the quality of the contour image of the product to be detected captured by the camera is improved.

Further, the camera is a 16K line scan camera. The 16K line scan camera has a high resolution, and can continuously collect images of the mobile phone flexible screen without interruption; the continuous acquisition of the mobile phone flexible screen moving in a straight line improves the image collection efficiency.

Further, the lens of the camera is a 0.8x telecentric lens. The use of a 0.8x telecentric lens can improve the clarity of the collected mobile phone flexible screen images, thereby greatly improving the visual inspection efficiency.

A detection method applied to high-speed line scan, which adopts the above-mentioned device applied to high-speed line scan detection to detect, comprising the following steps:

Step 1: Adjust the relative positions of the parallel light source device (1), the beam splitter (2), the backlight source (3) and the camera (4), and turn on the parallel light source device (1), Make the light spot fall in the middle of the field of view of the camera (4);

Step 2: pair the camera (4) with the computer, open the camera acquisition software, and set the exposure time;

Step 3: The product to be inspected (5) moves at a constant speed above the backlight source (3), and the camera (4) takes a picture of the product to be inspected (5).

The camera (4) described in the above step 3 shoots the product to be detected (5), and the details are as follows:

Step 3-1: the camera (4) locates the outer contour of the product to be detected (5);

Step 3-2: The camera (4) continuously shoots the outer contour of the product to be detected (5).

The beneficial effects of the present invention are as follows: a device applied to high-speed line scan detection and a detection method thereof, comprising a parallel light source device, a beam splitter, a backlight source and a camera, wherein the beam splitter is obliquely arranged at one end of the parallel light source device, The beam splitter, the backlight source and the camera are arranged in line. The parallel light source device adopts a telecentric optical path design, the output light has high parallelism and has the characteristics of ultra-high brightness, which can make the lens light pass more light, increase the light efficiency utilization rate, and reduce the required camera acquisition and exposure time. Axial light can reduce exposure by 13 times, thereby greatly improving the efficiency of visual inspection.

Description of drawings

FIG. 1 is a schematic structural diagram of a device applied to high-speed line scan detection in Embodiment 1 of the present invention.

in:

1-parallel light source device; 11-fixed body; 111-first base body; 112-second base body; 113-third base body; 12-heat dissipation device;

2- beam splitter;

3- Backlight;

4- camera;

5- Products to be tested.

Detailed ways

If certain terms are used in the description and claims to refer to specific components, those skilled in the art should understand that manufacturers may use different terms to refer to the same component. The description and claims do not use the difference in name as a way to distinguish components, but use the difference in function of the components as a criterion for distinguishing. As mentioned in the entire specification and claims, "comprising" is an open-ended term, so it should be interpreted as "including but not limited to". "Approximately" means that within an acceptable error range, those skilled in the art can solve technical problems within a certain error range, and basically achieve technical effects.

In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "upper", "lower", "front", "rear", "left", "right", horizontal" etc. is based on the accompanying drawings The orientation or positional relationship shown is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the indicated device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a reference to the present invention. limits.

In the present invention, unless otherwise expressly specified and limited, the terms "installed", "connected", "connected", "fixed" and other terms should be understood in a broad sense, for example, it may be a fixed connection or a detachable connection , or integrally connected; it can be a mechanical connection or an electrical connection; it can be a direct connection, or an indirect connection through an intermediate medium, or the internal communication between the two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments, but it is not intended to limit the present invention.

Example 1

As shown in FIG. 1, a device applied to high-speed line scan detection includes a parallel light source device 1, a beam splitter 2, a backlight source 3 and a camera 4. The beam splitter 2 is inclined and arranged at one end of the parallel light source device 1, and the beam splitter 2 , the backlight source 3 and the camera 4 are arranged in a line. The parallel light source device 1 adopts a telecentric optical path design, so that the parallelism of the emitted light is high, and it is convenient to realize rapid detection. For example, in the thermal detection of the flexible screen of the mobile phone, the device can be used for detection, which can image the slightly raised area caused by the thermal of the flexible screen of the mobile phone, and quickly capture and shoot. At the same time, due to the high parallelism and ultra-high brightness of the light generated by the device, it can increase the light flux of the lens and reduce the acquisition and exposure time required by the camera 4. Compared with ordinary coaxial light, the exposure can be reduced by 13 times. , thereby greatly improving the visual inspection efficiency.

The beam splitter 2 is inclined at 45°, which is used to reflect the light emitted by the parallel light source device 1 to the product through the beam splitter 2 , and the light is reflected by the product through the beam splitter 2 and finally enters the lens of the camera 4 .

Further, the parallel light source device 1 includes a fixed body 11 and an optical fiber point light source disposed in the fixed body 11 . This structural design effectively enhances the structural firmness of the entire device.

Further, the fixing body 11 is used to make the divergence angle of the light ≤ 1°. It ensures that the light output by the light source remains parallel and has a high degree of coaxiality, increases the amount of light passing through the lens, and reduces the required exposure time for camera 4 acquisition. Compared with ordinary coaxial light, the exposure can be reduced by 13 times, thereby greatly improving the visual inspection efficiency.

Further, the fixing body 11 includes a first base body 111 , a second base body 112 and a third base body 113 . One end of the first base body 111 is provided with a first connection port, and one end of the third base body 113 is provided with a first connection port corresponding to the first connection port. Two connection ports, two ends of the second base body 112 are respectively connected to the first connection port and the second connection port, and the third base body 113 extends outward along the light exit direction to form expansion ports. This structural design makes the divergence angle of the light ≤ 1°, which improves the utilization rate of the light source, so that the light can be guaranteed to propagate in the same direction during the transmission process. It has a reflection effect on light, which can reduce the loss of light in the transmission process and improve the brightness of the light spot.

Further, the first base body 111 has a built-in heat dissipation device 12, and the heat dissipation device 12 is used for heat dissipation. This structural design effectively prolongs the service life of the parallel light source device 1 and avoids the occurrence of equipment failure due to excessive heat generated by the light source during operation.

Further, the backlight source 3 is used to increase the backlight amount of the product 5 to be inspected. The purpose of adding the backlight is to assist the camera 4 to photograph the outer contour of the product 5 to be inspected, so that the camera 4 can locate and capture the product 5 to be inspected.

Further, the distance between the upper end surface of the backlight source 3 and the lower end surface of the product to be inspected 5 is 19.5 mm˜20.5 mm. This structural design enables a large amount of light to pass through the lens of the camera 4 , and improves the quality of the contour image of the product 5 to be inspected captured by the camera 4 .

Further, the distance between the lower end surface of the spectroscope 2 and the upper end surface of the product to be inspected 5 is 9.5 mm˜10.5 mm. This structural design enables a large amount of light to pass through the lens of the camera 4 , and improves the quality of the contour image of the product 5 to be inspected captured by the camera 4 .

Further, the distance between the end face of the lens of the camera 4 and the upper end face of the product 5 to be inspected is 105 mm˜145 mm. This structural design enables a large amount of light to pass through the lens of the camera 4 , and improves the quality of the contour image of the product 5 to be inspected captured by the camera 4 .

Further, the camera 4 is a 16K line scan camera 4. The 16K line scan camera 4 has a high resolution and can continuously capture images of the mobile phone flexible screen without interruption; the continuous acquisition of the mobile phone flexible screen moving in a straight line improves the acquisition of images efficiency.

Further, the lens of the camera 4 is a 0.8x telecentric lens. The use of a 0.8x telecentric lens can improve the clarity of the collected mobile phone flexible screen images, thereby greatly improving the visual inspection efficiency.

The working principle of a device applied to high-speed line scan detection: adjust the relative positions of the parallel light source device 1, the beam splitter 2, the backlight source 3, the camera 4 and the product to be detected 5, set up the corresponding detection program, and connect Computer, start the camera 4 acquisition software, set the appropriate exposure time, and then turn on the parallel light source device 1, so that the parallel light source device 1 emits a group of high-brightness light with high parallelism and high coaxiality, passing through the beam splitter 2. Total reflection, the light is reflected on the surface of the workpiece to be inspected, and then reflected by the surface of the workpiece to be inspected, and through the transmission effect of the beam splitter 2, the beam of light enters the camera 4 arranged above the workpiece to be inspected, and the backlight source 3 is used to increase the The amount of backlight assists the camera 4 to capture and photograph the outer contour of the product 5 to be inspected, which facilitates the camera 4 to locate the product to be inspected 5 . The device utilizes the light emitting characteristics of ultra-bright parallel coaxial light and parallel coaxial structure, which greatly increases the amount of light entering the lens, and makes the thermal effect of the product 5 photographed by the camera 4 more obvious.

Example 2

The present embodiment 2 provides a detection method applied to a high-speed line scan, which adopts a device applied to the high-speed line scan detection of the embodiment 1 for detection, and the details are as follows:

Step 1: Adjust the relative positions of the parallel light source device (1), the beam splitter (2), the backlight source (3) and the camera (4), and turn on the parallel light source device (1) so that the light spot falls on the camera (4) field of view. middle;

Step 3: The product to be detected (5) moves at a constant speed above the backlight source (3), and the camera (4) shoots the product to be detected (5).

The camera (4) of the above-mentioned step 3 shoots the product to be detected (5), and the details are as follows:

Step 3-2: The camera (4) continuously shoots the outer contour of the product (5) to be detected.

Based on the disclosure and teaching of the above specification, those skilled in the art to which the present invention pertains can also make changes and modifications to the above-described embodiments. Therefore, the present invention is not limited to the above-mentioned specific embodiments, and any obvious improvement, replacement or modification made by those skilled in the art on the basis of the present invention falls within the protection scope of the present invention. In addition, although some specific terms are used in this specification, these terms are only for convenience of description and do not constitute any limitation to the present invention.

Claims

A device applied to high-speed line scan detection, characterized in that it comprises a parallel light source device (1), a beam splitter (2), a backlight source (3) and a camera (4), wherein the beam splitter (2) is arranged in an inclined manner At one end of the parallel light source device (1), the beam splitter (2), the backlight source (3) and the camera (4) are arranged in a line.
A device applied to high-speed line scan detection according to claim 1, wherein:

The parallel light source device (1) comprises a fixed body (11) and an optical fiber point light source arranged in the fixed body (11).
A device applied to high-speed line scan detection according to claim 2, wherein:

The fixing body (11) is used to make the divergence angle of the light ≤ 1°.
A device applied to high-speed line scan detection according to claim 3, wherein:

The fixed body (11) includes a first base body (111), a second base body (112) and a third base body (113), one end of the first base body (111) is provided with a first connection port, and the third base body One end of (113) is provided with a second connection port corresponding to the first connection port, and both ends of the second base body (112) are respectively connected to the first connection port and the second connection port, so The third base body (113) extends outward along the light exit direction to form expansion ports.
A device applied to high-speed line scan detection according to claim 4, wherein:

A heat dissipation device (12) is built in the first base body (111), and the heat dissipation device (12) is used for heat dissipation.
A device applied to high-speed line scan detection according to claim 1, wherein:

The backlight source (3) is used to increase the backlight amount of the product (5) to be inspected.
A device applied to high-speed line scan detection according to claim 6, wherein:

The distance between the lower end face of the spectroscope (2) and the upper end face of the product to be detected (5) is 9.5mm to 10.5mm;

The distance between the upper end surface of the backlight source (3) and the lower end surface of the product to be inspected (5) is 19.5 mm˜20.5 mm.
A device applied to high-speed line scan detection according to claim 6, wherein:

The distance between the end face of the lens of the camera (4) and the upper end face of the product to be inspected (5) is 105mm˜145mm.
A detection method applied to a high-speed line scan detection device according to any one of claims 1 to 8, characterized in that it comprises the following steps:

Step 1: Adjust the relative positions of the parallel light source device (1), the beam splitter (2), the backlight source (3) and the camera (4), and turn on the parallel light source device (1), Make the light spot fall in the middle of the field of view of the camera (4);

Step 2: pair the camera (4) with the computer, open the camera acquisition software, and set the exposure time;

Step 3: The product to be inspected (5) moves at a constant speed above the backlight source (3), and the camera (4) takes a picture of the product to be inspected (5).
A kind of using method applied to the high-speed line scan detection device according to claim 9, is characterized in that:

The camera (4) described in the above step 3 shoots the product to be detected (5), and the details are as follows:

Step 3-1: the camera (4) locates the outer contour of the product to be detected (5);

Step 3-2: The camera (4) continuously shoots the outer contour of the product to be detected (5).