TWI806086B - Optical inspection system and method for collaborative inspection - Google Patents

Abstract

An optical inspection system and a method for collaborative inspection are provided. The system at least includes a first imaging unit and a second imaging unit that respectively includes an imaging circuit, a lens and a light source. The first imaging unit and the second imaging unit are collaboratively operated for capturing images of different portions of an object to be inspected. The optical inspection system includes a control unit. The first and second imaging units capture the images of the object according to instructions generated by the control unit so as to generate a first image and a second image. In the meantime, the light sources which are preferably the coaxial light sources are enabled to illuminate the object to be detected simultaneously or under a time-sharing process. The light sources can be operated as front lights and back lights for the first imaging unit and the second imaging unit to captures images of the object in different directions through their lenses respectively.

Description

Optical detection system and collaborative detection method

The description discloses an optical detection technology, which particularly refers to an optical detection system and a cooperative detection method that can cooperatively detect both sides of an object to be tested.

Conventional defect detection using optical principles requires a combination of different lighting equipment to completely detect the object to be inspected, such as backlight and front lighting. The conventional technology requires a backlight source to be installed under the product, so it is impossible to perform backside inspection at the same time. To perform multi-faceted inspections of such products, it is necessary to take multiple shots by changing the illuminated facet of the product.

However, there is still a known imaging system for detecting a specific object as shown in FIG. The first light source device 103 and the first photographic lens 101 on the same side and the second light source device 104 and the second photographic lens 102 on the same side are used to photograph the reverse side of the object 10 to be inspected.

The description discloses an optical detection system and its cooperative detection method. The main device in the system includes a first image-taking unit, which includes a first image-taking circuit, a first lens and a first light source, and a second image-taking unit, which includes The second image capturing circuit, the second lens and the second light source. The optical detection system is provided with a control unit, and the first imaging unit and the second imaging unit respectively photograph different parts of an object to be detected according to the instructions generated by the control unit to form the first image and the second image, which are activated simultaneously or in time division The first light source and the second light source irradiate the object to be detected, and respectively become the front light and backlight of the object to be detected in different directions taken by the first imaging circuit through the first lens and the second image capturing circuit through the second lens.

According to the embodiment of the cooperative detection method operated by the optical detection system, firstly, an object to be detected is prepared, and then the first imaging unit and the second imaging unit of the optical detection system are initialized, and then an illumination control instruction generated by the control unit can be simultaneously Or turn on the first light source and the second light source in time division to irradiate the object to be inspected, and control the first imaging unit to photograph the object to be inspected according to a photographing control command generated by the control unit, generate the first detection image, and control the second imaging unit The object to be detected is photographed to generate a second detection image.

Preferably, the first light source or the second light source can be a coaxial light, and the coaxial light can be designed to pass through a semi-transparent and semi-reflective beam splitter. The transflective and semi-reflective spectroscopic sheet irradiates to the first lens or the second lens.

In one embodiment, the first image-taking unit and the second image-taking unit are respectively equipped with a first auxiliary light source and a second auxiliary light source, which are used to assist in improving the irradiation range of the first light source and the first light source and forming a backlight. range. Wherein, the control unit includes a light source control circuit for controlling the operation of the first light source, the second light source, the first auxiliary light source and the second auxiliary light source.

Preferably, the control unit in the system is a main control computer, and the main control computer generates instructions to control the operation of the first imaging unit and the second imaging unit, and the storage device can store the first imaging unit according to an identification code of the object to be detected. The detection image produced by the imaging unit and the second imaging unit.

The instruction can be a lighting control instruction generated by the main control computer, and the control light sources can be turned on at the same time or in time-sharing to irradiate the object to be detected, wherein, when the first light source illuminates the object to be detected, the first light source can be used as the first image-taking The positive light of the unit and the backlight of the second imaging unit; when the second light source illuminates the object to be detected, it can be used as the positive light of the second imaging unit and the backlight of the first imaging unit.

In order to further understand the features and technical content of the present invention, please refer to the following detailed description and drawings related to the present invention. However, the provided drawings are only for reference and description, and are not intended to limit the present invention.

The implementation of the present invention is described below through specific specific examples, and those skilled in the art can understand the advantages and effects of the present invention from the content disclosed in this specification. The present invention can be implemented or applied through other different specific embodiments, and various modifications and changes can be made to the details in this specification based on different viewpoints and applications without departing from the concept of the present invention. In addition, the drawings of the present invention are only for simple illustration, and are not drawn according to the actual size, which is stated in advance. The following embodiments will further describe the relevant technical content of the present invention in detail, but the disclosed content is not intended to limit the protection scope of the present invention.

It should be understood that although terms such as "first", "second", and "third" may be used herein to describe various elements or signals, these elements or signals should not be limited by these terms. These terms are mainly used to distinguish one element from another element, or one signal from another signal. In addition, the term "or" used herein may include any one or a combination of more of the associated listed items depending on the actual situation.

Generally, when performing defect detection, it is necessary to use different lighting equipment in combination to form a multi-directional light that illuminates an object to be inspected. Backlight and front light can be roughly classified. To perform multi-directional inspection on such products, it is necessary to change the lighting of the product Faced with multiple shots. This disclosure proposes an optical detection system and its cooperative detection method. The system is equipped with at least two groups of imaging units to perform a cooperative detection operation, and can take photographs and detection images of an object to be detected in different directions.

FIG. 2 shows a schematic diagram of one embodiment of the optical detection system proposed in the disclosure. In this embodiment figure, the optical equipment in the optical detection system mainly includes a first imaging unit 21 and a second imaging unit 22, and the control device can be The control unit 207 is represented in the figure.

According to the embodiment shown, the main components of the first image capturing unit 21 include the first image capturing circuit 201, the first lens 203 and the first light source 205, and the main components of the second image capturing unit 22 include the second image capturing circuit 202, the second The lens 204 and the second light source 206 . Wherein the first image-taking circuit 201 and the second image-taking circuit 202, such as photosensitive elements and related control circuits in a camera, are respectively connected to the first lens 203 and the second lens 204, and wherein the light source can also adopt a kind of light source that can generate light in the same direction as the lens. The coaxial light source of the light can make the light reflected by the object to be detected and the lens be on the same axis. Its main purpose is to form the front light and backlight of each imaging unit when the object to be detected is detected.

The first image-taking circuit 201 and the second image-taking circuit 202 are electrically connected to the control unit 207 in the system, and can be realized by a main control computer, so that the image-taking unit can control the shooting position according to the instructions generated by the control unit 207, and are opposite to each other. The object to be inspected 20 placed on the carrying device 200 takes an inspection image. During the operation of the optical detection system, according to one embodiment, the operator can set the imaging circuits and lenses in the first imaging unit 21 and the second imaging unit 22 through the control interface on the main control computer (control unit 207). Detection parameters, such as moving the position where the lens captures the object 20 to be detected by the driving mechanism in the first imaging unit 21 and the second imaging unit 22, setting the shooting angle and related shooting parameters (such as aperture, shutter and photosensitive temperature, etc.), and also includes setting the operating parameters of the first light source 205 and the second light source 206, such as on-off sequence, brightness, color temperature and other parameters.

The optical detection system can additionally be hung with an auxiliary light source, as shown in FIG. There is an auxiliary light source, as shown in the schematic diagram, the first auxiliary light source 301 and the second auxiliary light source 302 mounted on the first lens 203 and the second lens 204 respectively, the purpose of which is to assist in improving the above-mentioned first light source 205 and first light source 206 The range of illumination and the range of forming backlight.

According to an embodiment, the first auxiliary light source 301 can be a ring-shaped light source mounted on the first lens 203, which serves as an auxiliary light source for the front of the object 20 to be detected when the first imaging circuit 201 takes pictures, and also serves as a second imaging circuit. 202 to photograph the backlight of the same detected object in different directions. Similarly, the second auxiliary light source 302 can be a ring-shaped light source mounted on the second lens 204. In addition to being used as a front light source for the second image capturing circuit 202 to photograph the detected object 20, it can also be used as the first image capturing circuit 201 at the same time. The backlight of the object 20 to be inspected is photographed.

For a circuit embodiment of the optical detection system, refer to FIG. 4 , which shows a circuit block diagram.

In the part of optical detection, it mainly includes a first imaging unit 41 and a second imaging unit 42. The first imaging unit 41 includes a first communication unit 411, a first light source controller 412 and a controlled first light source 413. , the first imaging circuit 414 and the first lens 415; the second imaging unit 42 correspondingly includes the first communication unit 421, the second light source controller 422 and the controlled second light source 423, the second imaging circuit 424 and the second lens 425 .

The control unit in the optical detection system can be divided into the control host 45 and the light source control circuit 43 according to the function. The control host 45 can connect the first communication unit 411 in the first imaging unit 41 in a specific communication mode through the communication circuit. And the second communication unit 421 of the second image capturing unit 42 , through which commands can be transmitted to control the operation of each image capturing circuit and lens, and receive the detection data formed after shooting. The light source control circuit 43 is electrically connected to the first light source controller 412 in the first image capturing unit 41, thereby controlling the operation of the first light source 413, and the light source control circuit 43 is electrically connected to the second light source controller of the second image capturing unit 42. The controller 422, thereby controlling the operation of the second light source 423. The first light source controller 412 of the first light source 413 mainly determines the operating parameters of the first light source 413 according to the control command generated by the light source control circuit 43, such as the above-mentioned opening and closing sequence, brightness and color temperature, etc., and the second light source 423 similarly Controlled by the second light source controller 422 , it operates according to the control command generated by the light source control circuit 43 .

When the optical detection system is in operation, the control unit is respectively connected to the first communication unit 411 of the first imaging unit 41 and the second communication unit 421 of the second imaging unit 42 through a communication line to transmit instructions, which can be controlled separately. Respective imaging circuits and light sources. The first image capturing unit 41 and the second image capturing unit 42 respectively photograph different parts of the object to be detected according to the instructions generated by the control unit (the control host 45 and the light source control circuit 43), forming static or dynamic first images and second images respectively , wherein the first light source 413 and the second light source 423 can be activated simultaneously or in time-division to irradiate the object to be detected, and become the first imaging circuit 414 passing through the first lens 415 and the second imaging circuit 424 passing through the second lens 425 respectively. Shoot the positive light and backlight of the object to be detected in different directions.

According to the above embodiment, it can be seen that the optical detection system is mainly composed of two groups of imaging units ( 41 , 42 ) that can work together, and the structural design of one of the imaging units can refer to the embodiment diagram shown in FIG. 5 .

Figure 5 shows the image pickup circuit 501 in the image pickup unit, connected to a lens 503, the set light source is preferably a coaxial light source 507, and an auxiliary light source can be mounted on the lens 503, such as the ring light source 505 shown in the figure .

In the imaging unit of this example, the light source is coaxial light, and a semi-transparent and semi-reflective beam splitter 509 is provided on the path of the object 513 to be detected on the carrier device 511 photographed by the lens 503, which is used to reflect the light emitted by the coaxial light source 507 Shine toward the object to be detected 513, and the light reflected from the object to be detected 513 can pass through the semi-transparent and semi-reflective beam splitter 509 and then enter the lens 503, where it is sensed by a photosensitive element in the imaging circuit 501 to generate a detection image .

Correspondingly, the mechanism design of another imaging unit in the optical detection system is also shown in the legend shown in FIG. 5 , which is provided with another coaxial light source and a corresponding semi-transparent and semi-reflective beam splitter. This semi-transparent and semi-reflective spectroscopic sheet reflects two coaxial light rays in the imaging units on both sides to different parts (such as the front and back) of the detected object 513, and then is reflected by the detected object 513 and penetrates the respective semi-transparent and semi-reflective The beam splitter shoots to the first lens and the second lens in the two imaging units.

According to the description of the above embodiment, as shown in Fig. 2, Fig. 3 and Fig. 4, the control host 45 in the control unit generates commands to control the operation of the first image capturing unit 41 and the second image capturing unit 42, and the light source control circuit 43 The generated control instructions are used to control the first light source 413 and the second light source 423, and can further control the operation of the first auxiliary light source and the second auxiliary light source. The operation of the light source and the imaging circuit can not only operate simultaneously to capture the object to be detected In addition to the detected images, it can also be run in a time-sharing manner. For a related timing example, refer to FIG. 6 . For a system running a cooperative detection method, refer to the flow chart of the embodiment shown in FIG. 7 .

In this process, an object to be detected is initially prepared and placed on the carrier device in the system (step S701), and then the first imaging unit and the second imaging unit are initialized according to the initialization command issued by the control unit (step S701). S703), including initializing the imaging circuit, lens, light source, power supply and related circuits.

Afterwards, the system starts to operate according to the control command of the control unit. You can refer to the timing diagram of the operation of the light source and the imaging circuit shown in FIG. 6 , but the actual implementation is not limited to the timing example shown in FIG. 6 . When the system is running, the control unit generates a lighting control command, and transmits the lighting control command to the first imaging unit and the second imaging unit through the communication line, so as to turn on the first light source 413 and the second light source 423 at the same time or time-sharing To irradiate the object to be detected (step S705 ), the illustration shows that the first light source 413 is turned on earlier than the second light source 423 by an illumination control time difference t1.

According to the timing diagram of the operation of the optical detection system shown in Figure 6, the control unit then generates a photography control command, which is sent to the first imaging unit and the second imaging unit in the system through the communication line, so as to drive The mechanism positions the first lens and the second lens in the first imaging unit and the second imaging unit to a certain position and starts to photograph the object to be detected. During the shooting process, the first light source and the second light source respectively become the first imaging circuit The front light and backlight of the object to be detected in different directions are photographed through the first lens and the second image pickup circuit through the second lens. In this example, the first imaging circuit 414 is activated first, and then the control of shooting the object to be detected can be started (step S707), and the first detection image is generated (step S709). After the shooting control time difference t2, the second imaging circuit 424 is activated, And control to photograph the object to be detected (step S711 ), and generate a second detection image (step S713 ).

After the first image-taking unit and the second image-taking unit generate the first detection image and the second detection image respectively, they can be sent back to the control unit, such as the control host 45 shown in FIG. An identification code (ID) stores the generated first and second detection images (step S715 ). Therefore, in the storage device of the control host 45, the corresponding detection data can be stored respectively according to the identification codes of different objects to be detected. After this process is completed, the optical detection system can be reset (step S717 ) to prepare for the next collaborative detection operation.

To sum up, according to the optical detection system and cooperative detection method described in the above embodiments, the system is mainly composed of two groups of imaging units plus a control unit and related circuits. Using coaxial light as the light source, this novel inspection system can perform multi-face inspection to obtain images of different parts of an object to be inspected at a time, and can also inspect at the same time.

The content disclosed above is only a preferred feasible embodiment of the present invention, and does not therefore limit the scope of the patent application of the present invention. Therefore, all equivalent technical changes made by using the description and drawings of the present invention are included in the application of the present invention. within the scope of the patent.

10: The substance to be detected 100: Carrying mechanism 103: The first light source device 101 first camera lens 104 second light source device 102: Second camera lens 21, 21': the first imaging unit 201: The first imaging circuit 203: First shot 205: The first light source 22, 22': the second imaging unit 202: The second imaging circuit 204: Second shot 206: Second light source 200: carrying device 20: Object to be detected 207: Master computer 301: The first auxiliary light source 302: Second auxiliary light source 45: Control host 43: Light source control circuit 41: The first imaging unit 411: The first communication unit 412: The first light source controller 413: The first light source 414: The first imaging circuit 415: first shot 42: The second imaging unit 421: The first communication unit 422: Second light source controller 423: Second light source 424: The second imaging circuit 425:Second shot 501: Image acquisition circuit 503: Lens 505: ring light source 507: Coaxial light source 507: Semi-transparent and semi-reflective beam splitter 511: carrying device 513: Object to be detected t1: lighting control time difference t2: Photography Control Time Lag S701～S717: steps

Figure 1 shows a conventional imaging system for detecting specific objects; Figure 2 shows a schematic diagram of one embodiment of an optical detection system; Fig. 3 shows the second schematic diagram of the embodiment of the optical detection system; 4 shows a schematic diagram of a circuit block embodiment of an optical detection system; Fig. 5 shows the embodiment diagram of the imaging unit in the optical detection system; FIG. 6 shows a timing diagram of the operation of the optical detection system; and Fig. 7 shows a flowchart of an embodiment of a cooperative detection method using an optical detection system.

21: The first imaging unit

201: The first imaging circuit

203: First shot

205: The first light source

22: The second imaging unit

202: The second imaging circuit

204: Second shot

206: Second light source

200: carrying device

20: Object to be detected

207: Control unit

Claims (10)

A cooperative detection method applied to an optical detection system, comprising: preparing an object to be detected; initializing a first imaging unit and a second imaging unit of the optical detection system, wherein the first imaging unit is provided with a first imaging unit An image capturing circuit, a first lens and a first light source, the second image capturing unit is provided with a second image capturing circuit, a second lens and a second light source; according to an illumination control instruction generated by a control unit, the Or turn on the first light source and the second light source to illuminate the object to be inspected in time-sharing; and control the first imaging unit to photograph the object to be inspected according to a photographing control command generated by the control unit to generate a first inspection image, and controlling the second imaging unit to photograph the object to be detected to generate a second detection image, wherein the first light source and the second light source respectively become the first imaging circuit through the first lens and the second imaging circuit The circuit shoots the front light and back light of the object to be detected in different directions through the second lens. The collaborative detection method as described in claim 1, wherein the first image-taking unit and the second image-taking unit of the optical detection system are respectively provided with a first auxiliary light source and a second auxiliary light source for assisting in improving the first A light source and the irradiation range of the first light source and the range forming the backlight. The cooperative detection method as described in claim 1, wherein the control unit generates instructions for controlling the operation of the first image capturing unit and the second image capturing unit, and stores the first image capturing according to an identification code of the object to be detected The unit generates the first detection image and the second detection image generated by the second imaging unit. The cooperative detection method as described in claim 1, wherein the first light source or the second light source of the optical detection system is a coaxial light, wherein the first light source illuminates the object to be detected, as the first imaging unit The positive light and the backlight of the second imaging unit; the second light source illuminates the object to be detected as the positive light of the second imaging unit and the backlight of the first imaging unit. The cooperative detection method as described in any one of claims 1 to 4, wherein, according to According to the illumination control instruction, the first light source is turned on earlier than the second light source by an illumination control time difference; according to the photography control instruction, the first imaging circuit is first activated to photograph the object to be detected, and after a photography control time difference, Start the second imaging circuit to photograph the object to be detected. An optical detection system, comprising: a first imaging unit, provided with a first imaging circuit, a first lens and a first light source; a second imaging unit, provided with a second imaging circuit, a second lens and a second light source; and a control unit electrically connected to the first imaging unit and the second imaging unit; wherein the optical detection system operates a cooperative detection method, including: preparing an object to be detected; initializing the The first image-taking unit and the second image-taking unit of the optical detection system; according to an illumination control command generated by the control unit, the first light source and the second light source are turned on simultaneously or in time-division to illuminate the object to be detected; and according to A photography control command generated by the control unit controls the first imaging unit to photograph the object to be detected to generate a first detection image, and controls the second imaging unit to photograph the object to be detected to generate a second detection image, Wherein the first light source and the second light source respectively become the front light and the back light of the first image-taking circuit through the first lens and the second image-taking circuit through the second lens to photograph the object to be detected in different directions. The optical detection system as described in Claim 6, wherein the first light source or the second light source is coaxial light, which reflects the light onto the detected object through a semi-transparent and semi-reflective beam splitter, and then the detected object reflect and pass through the transflective beam splitter to the first lens or the second lens. The optical detection system as described in claim 6, wherein the first image-taking unit and the second image-taking unit are respectively provided with a first auxiliary light source and a second auxiliary light source for assisting in improving the first light source and the second light source. A range of irradiation of a light source and a range of forming a backlight. The optical detection system as claimed in claim 6, wherein the control unit generates control The first image-taking unit and the second image-taking unit operate according to an identification code of the object to be detected and store the detection images produced by the first image-taking unit and the second image-taking unit. The optical inspection system as described in claim 6, wherein an illumination control command is generated in the control unit, and the illumination control command is transmitted to the first imaging unit and the second imaging unit through the communication line, so as to simultaneously or Turn on the first light source and the second light source in time-sharing to irradiate the object to be detected; the control unit generates a photography control command, and transmits the photography control command to the first imaging unit and the second imaging unit through the communication line; The image unit is used to make the first lens and the second lens reach a certain position through a mechanism to start photographing the object to be inspected.

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