TWI794731B - Air floatation platform and optical inspection system comprising thereof - Google Patents

Abstract

The present invention provides a air floatation platform for placing a test workpiece. The air floatation platform comprises a supporting platform and a hollow structure carrier arranged on the supporting platform. The hollow structure carrier has a bearing surface and a supporting surface, so that the test workpiece is carried on the bearing surface. The hollow structure carrier comprises a hollow structure, and an inner side wall defines a bearing surface opening and a supporting surface opening. The test workpiece, the hollow structure carrier and the supporting platform constitute a closed cavity. Wherein, a plurality of exhaust holes are formed on the inner side wall, so as to output air in the closed cavity through a positive pressure to provide a central air floating zone.

Description

Air bearing platform and its optical detection system

The invention provides a stage structure, in particular to an air-floating stage capable of floating a workpiece to be tested and an optical detection system thereof.

With the development of the fully automated industry, Automatic Optical Inspection (AOI) is a common representative method in industrial processes. To detect defects such as foreign objects or abnormal patterns, and because of the non-contact inspection, it can be used to inspect semi-finished products during the production line. Based on the advantages of automatic optical identification system detection, it has been widely used in the visual inspection of circuit board assembly production lines in the electronics industry and replaced the previous manual visual inspection (Visual Inspection).

Generally, the optical inspection platform performs front inspection and back inspection, mainly by taking double-sided images of the workpiece through the optical inspection device. After turning over, the second set of optical detection devices on the moving line will take a second image of the workpiece on the moving line. Another way is to take the image of the first side of the workpiece by the optical detection device on the moving path of the workpiece, and after the workpiece is turned over by the turning device, the original moving line returns and the optical detection device takes the image of the first side of the workpiece Two-sided image, so as to obtain a double-sided image of the workpiece to be measured. Regardless of the first method or the second method above, it is necessary to design at least two or more platforms on the moving line (such as the first group of optical detection devices, the second group of optical detection devices, and the turning device) In order to realize the function of double-sided detection, it will not only increase the cost of manufacturing the detection equipment, but also take up too much space.

The main purpose of the present invention is to provide an air bearing platform for placing a workpiece to be tested. The air bearing platform includes a support platform and a hollow structural carrier arranged on the support platform. The hollow structure carrier has a carrying surface and a supporting surface, so that the workpiece to be measured is carried on the carrying surface. Wherein the hollow structural carrier defines a loading surface opening and a supporting surface opening through an inner wall. Wherein the workpiece to be tested, the hollow structural carrier and the supporting platform form a closed cavity. Wherein a plurality of exhaust holes are formed on the inner wall to output air in the closed cavity through a positive pressure supply device to form a central air flotation area.

Another object of the present invention is to provide an optical inspection system for inspecting a workpiece to be inspected. The system includes a support platform, a hollow structure carrier arranged on the support platform, a first image capture device, and an image detection device. The hollow structure carrier has a bearing surface and a supporting surface, so that the workpiece to be measured is carried on the bearing surface, wherein the hollow structure carrier defines a bearing surface opening and a supporting surface opening through an inner side wall. The first image capturing device is arranged on one side of the supporting surface, and is used for capturing the first surface image of the workpiece to be measured. The image detection device is coupled to the first image capture device to detect the first surface image of the workpiece to be measured. Wherein the workpiece to be tested, the hollow structural carrier and the supporting platform form a closed cavity. Wherein a plurality of exhaust holes are formed on the inner wall to output air in the closed cavity through a positive pressure supply device to form a central air flotation area.

Therefore, the present invention can perform detection from the back of the carrier, increasing the flexibility of equipment configuration and moving lines. On the other hand, the present invention can level the surface of the workpiece to be tested while photographing the workpiece to be tested, and use positive pressure to prop up the workpiece to be tested evenly, thereby increasing the accuracy of the detection results.

The detailed description and technical contents of the present invention are described as follows with respect to the accompanying drawings. Furthermore, for the convenience of explanation, the proportions of the drawings in the present invention are not necessarily drawn according to the actual scale, but are exaggerated. These drawings and their proportions are not intended to limit the scope of the present invention.

The present invention is used to carry out back detection or double-side detection of the workpiece to be tested, and transmit the captured image to the automatic optical inspection equipment, so as to confirm the defects of the workpiece to be tested by machine vision through the automatic optical inspection equipment, thereby completing the automatic optical inspection Procedure (Automated Optical Inspection).

In an embodiment of the present invention, the workpiece to be tested can be any substrate, such as a printed circuit board (Printed Circuit Board), a flexible printed circuit board (Flexible Printed Circuit, FPC), a wafer, a light guide plate, a polarizer, Panels, or other such workpieces, are not limited in the present invention.

For one embodiment of the present invention, please refer to "Fig. 1", which is a schematic block diagram of a single-sided detection embodiment of the optical detection system in the present invention, as shown in the figure.

The present invention provides an optical inspection system 100 for inspecting a workpiece W to be inspected. The optical detection system 100 includes a support platform 10 , a hollow structure carrier 20 , a first image capture device 30 , and an image detection device 50 .

The support platform 10 is used for setting the hollow structure carrier 20 , and the support platform 10 can be any mechanism or device to make one side of the hollow structure carrier 20 form a closed area. The combination of the support platform 10 and the hollow structure carrier 20 will constitute an air bearing platform. When the workpiece W to be measured is placed on the other side of the hollow structure carrier 20, the support platforms 10 on both sides and the workpiece W to be measured will The inner side of the hollow structure carrier 20 forms a closed cavity CB.

The hollow structure carrier 20 is arranged on the supporting platform 10, and has a carrying surface 21 and a supporting surface 22. The workpiece W to be measured is configured to be carried on the carrying surface 21, the supporting surface 22 is combined with the supporting platform 10, and forms a closed section through the supporting platform 10 or the cavity of the supporting platform 10, wherein the hollow structure carrier 20 sees through the inner wall 23 defines the loading surface opening 231 and the supporting surface opening 232 . A plurality of exhaust holes 233 are formed on the inner wall 23 to output air in the closed cavity CB through the positive pressure supply device 234 to form a central air flotation area. In the drawings, the bearing surface opening 231 is directed toward the upper direction in FIG. 1 (such as arrow A1), the supporting surface opening 232 is directed toward the lower direction in FIG. The wall surface in the direction, the ring-shaped outer wall surface 24 is the outer wall surface of the hollow structure carrier 20 away from the hollow structure, the upper side plane of the hollow structure carrier 20 is the bearing surface 21, and the lower side plane of the hollow structure carrier 20 is the supporting surface twenty two. In one embodiment, a plurality of adsorption holes 211 are formed on the bearing surface 21 to form a peripheral adsorption area, so that the workpiece W to be measured is adsorbed on the bearing surface 21 through the negative pressure providing device 214 .

In one embodiment, the hollow structural carrier 20 is circular; in other embodiments, the hollow structural carrier 20 can also be square, polygonal, irregular or other arbitrary shapes in addition to circular , these shapes are not within the scope of the present invention.

The first image capture device 30 is disposed on one side of the supporting surface 22 for capturing a first surface image of the workpiece W to be measured. The first image capture device 30 faces the direction of the opening 232 of the supporting surface (such as arrow A1), and is used to capture the backside image of the workpiece W to be measured through the opening 232 of the supporting surface; the first surface image referred to herein refers to the workpiece W to be measured The position relative to the hollow structure carrier 20 does not necessarily refer to the front or back of the workpiece W to be tested, which will be described here first. In one embodiment, the first image capturing device 30 includes an auxiliary light source 31 and an image sensing device 32 . The auxiliary light source 31 provides light to the first surface of the workpiece W to be measured. The image sensing device 32 is used to obtain a first surface image of the workpiece W to be measured. In one embodiment, the auxiliary light source 31 may be, for example but not limited to, a coaxial light source, a ring light source, a side light source, or an ambient light source, etc., which are not limited in the present invention. In one embodiment, the image sensing device 32 may be a line scan camera (Line Scan Camera) or an area scan camera (Area Scan Camera), which is not limited in the present invention.

The image detection device 50 is coupled to the first image capture device 30 to detect the first surface image of the workpiece W to be measured. The image detection device 50 can acquire defects on the workpiece W to be tested through traditional image analysis algorithms, or analyze images through machine learning (Machine Learning), deep learning (Deep Learning), or other similar neural networks and obtain detection results, and then No limitation is imposed in the present invention. In one embodiment, the image detection device 50 can process the image and obtain the detection result through visual inspection by personnel, which is not limited in the present invention.

For another embodiment of the present invention, please refer to "Fig. 2", which is a schematic block diagram of an embodiment of the double-sided detection of the optical detection system in the present invention, as shown in the figure.

The main difference between this embodiment and the previous embodiment lies in the number and installation positions of the image capture devices, and other similar parts will not be repeated hereafter.

The present invention provides an optical inspection system 200 for double-sided inspection. In this embodiment, the first image capturing device 30 is disposed on one side of the support surface 22 for capturing a first surface image of the workpiece W to be measured. The first image capturing device 30 faces toward the opening 232 of the supporting surface (as shown by arrow A2 ), and is used for capturing the backside image of the workpiece W to be measured through the opening 232 of the supporting surface.

In order to photograph the other side (second side image) of the workpiece W to be measured, this embodiment further includes a second image capture device 40, which is arranged on one side of the bearing surface 21, to obtain the image of the workpiece W to be measured. Second image. The second image capture device 40 faces toward the opening 231 of the carrying surface (as shown by arrow A3), and is used to capture a front image of the workpiece W to be measured. In one embodiment, the second image capturing device 40 includes an auxiliary light source 41 and an image sensing device 42 . The auxiliary light source 41 provides light to the second surface of the workpiece W to be measured. The image sensing device 42 is used to obtain a second surface image of the workpiece W to be measured. In one embodiment, the auxiliary light source 41 may be, for example but not limited to, a coaxial light source, a ring light source, a side light source, or an ambient light source, etc., which are not limited in the present invention. In one embodiment, the image sensing device 42 may be a line scan camera (Line Scan Camera) or an area scan camera (Area Scan Camera), which is not limited in the present invention.

The image detection device 50 is coupled to the first image capture device 30 and the second image capture device 40 to receive the first surface image and the second surface image of the workpiece W to be measured, and the first surface image and the second surface image Image detection is performed on the second-side images separately, so as to realize the function of double-side detection.

Two different specific embodiments of the air bearing platform in the present invention will be described below. The first embodiment Please refer to "Fig. 3", "Fig. 4", "Fig. 5" and "Fig. 6" together, which are the schematic view of the appearance, the side view, and the cross-sectional view of the air bearing platform of the first embodiment of the present invention. , and the top view of the air bearing platform, as shown in the figure.

This embodiment discloses an optical inspection system 300 for inspecting a workpiece W to be inspected. The optical detection system 300 mainly includes an air bearing stage SA, a first image capture device 30A, a second image capture device 40A, and an image detection device 50A.

The functions of the first image capture device 30A, the second image capture device 40A, and the image detection device 50A have been described in detail in the previous embodiments, and the hardware configuration thereof will not be repeated here.

The first image capture device 30A is arranged on one side of the support surface 22A of the air bearing stage SA to capture the image of the first surface of the workpiece W to be measured. The first image capture device 30A includes an auxiliary light source 31A and an image sensor Measuring device 32A; the second image capturing device 40A is arranged on one side of the bearing surface 21A of the air bearing stage SA to capture the second surface image of the workpiece W to be measured, and the second image capturing device 40A includes an auxiliary light source 41A and image sensing device 42A. The image detection device 50A is coupled to the first image capture device 30A and the second image capture device 40A.

Please refer to "Fig. 5" and "Fig. 6" for the detailed structure of the air bearing stage SA in this embodiment. The air bearing platform SA mainly includes a flat plate of transparent material 10A, and a hollow structure carrier 20A arranged on the flat plate of transparent material 10A. In this embodiment, the hollow structure carrier 20A includes bearing surfaces 21A and support surfaces 22A arranged on both sides. The hollow structure in the middle of the hollow structure carrier 20A is a circular through hole 25A, and the circular through hole 25A passes through the hollow The center of the structural carrier 20A thus forms a loading surface opening 251A and a supporting surface opening 252A on both sides. The transparent material plate 10A closes the opening 252A of the supporting surface to close the circular through hole 25A in the side direction. When the workpiece W to be measured is placed on the bearing surface 21A, the workpiece W to be measured, the hollow structure carrier 20A and the transparent material plate 10A form a closed cavity CB1. With the configuration of the transparent material plate 10A, the first image capture device 30A (as shown in FIG. 4 ) can capture the first surface image of the workpiece W to be measured through the transparent material plate 10A.

In this embodiment, the bearing surface 21A is provided with an adsorption hole 211A for absorbing the workpiece W to be measured. The adsorption hole 211A is connected to the through hole 213A on the annular outer wall surface 24A via the channel 212A inside the hollow structure carrier 20A, so as to It is connected to a vacuum device (not shown) through the through hole 213A, so as to form a negative pressure providing device together with the vacuum device. In one embodiment, the vacuum device may be, for example, a vacuum pump or a vacuum unit, which is not limited in the present invention.

The inner side wall 23A is provided with an exhaust hole 231A for outputting air in the closed cavity CB1 to form the central air flotation area FA. The exhaust hole 231A is connected to the annular outer wall surface through the channel 232A inside the hollow structure carrier 20A. The through hole 233A on 24A is connected to the gas output device (not shown) through the through hole 233A, so as to form a positive pressure providing device together with the gas output device. In one embodiment, the gas output device may be, for example, an electric gas pump, or a gas cylinder, etc., which are not limited in the present invention.

In this embodiment, the adsorption holes 211A and the exhaust holes 231A are distributed in a staggered manner on the hollow structural carrier 20A in a circular manner, so that the through holes 213A and the through holes 233A can alternately be arranged on the annular outer wall surface 24A.

In one embodiment, a guide inclined surface 26A is provided at the inner periphery of the hollow structure carrier 20A toward the supporting surface opening 252A, and the guiding inclined surface 26A is tapered from the supporting surface opening 252A toward the bearing surface opening 251A, and passes through the guiding inclined surface 26A Therefore, the position of the workpiece W to be measured corresponding to the central air-floating area FA is protected from light.

The following describes the second embodiment of the present invention. Please refer to "Fig. 7", "Fig. 8" and "Fig. 9" together, which are the schematic appearance, side view and air bearing of the second embodiment of the present invention. A cross-sectional schematic diagram of the platform is shown in Fig.

This embodiment discloses an optical inspection system 400 for inspecting a workpiece W to be inspected. The optical detection system 400 mainly includes an air bearing stage SB, a first image capture device 30B, a second image capture device 40B, and an image detection device 50B.

The functions of the first image capture device 30B, the second image capture device 40B, and the image detection device 50B have been described in detail in the previous embodiments, and the hardware configuration thereof will not be repeated here.

The first image capture device 30B is set on one side of the support surface 22B of the hollow structure carrier 20B to capture the first surface image of the workpiece W to be measured. The first image capture device 30B includes an auxiliary light source 31B and an image sensor Measuring device 32B; the second image capturing device 40B is arranged on one side of the carrying surface 21B of the hollow structure carrier 20B to capture the second surface image of the workpiece W to be measured, and the second image capturing device 40B includes an auxiliary light source 41B and image sensing device 42B. The image detection device 50B is coupled to the first image capture device 30B and the second image capture device 40B.

For the detailed structure of the air bearing stage SB in this embodiment, please refer to "Fig. 9". In this embodiment, the air bearing platform SB mainly includes a box body 10B and a hollow structure carrier 20B disposed on the box body 10B. In this embodiment, the hollow structure carrier 20B includes bearing surfaces 21B and support surfaces 22B arranged on both sides. The hollow structure in the middle of the hollow structure carrier 20B is a circular through hole 25B, and the circular through hole 25B passes through the hollow The center of the structural carrier 20B thereby forms a bearing surface opening 251B and a supporting surface opening 252B on both sides. The box body 10B is combined with the opening 252B of the supporting surface, and has an accommodating space 11B for accommodating the first image capturing device 30B. When the workpiece W to be measured is placed on the bearing surface 21B, the workpiece W to be measured, the hollow structural carrier 20B and the accommodation space 11B of the box 10B form a closed cavity CB2. The bearing surface 21B is provided with an adsorption hole 211B for absorbing the workpiece W to be measured, and the inner wall 23B is provided with an exhaust hole 231B for outputting air in the closed cavity CB2 to form a central air flotation area FB. In addition to being disposed on the hollow structure carrier 20B, the exhaust hole may also be disposed inside the box body 10B, which is not limited in the present invention.

With the configuration of the box 10B, the first image capturing device 30B can capture the first surface image of the workpiece W to be measured through the opening 252B of the support surface of the hollow structure carrier 20B.

In summary, the present invention can perform detection from the back of the carrier, increasing the flexibility of equipment configuration and moving lines. On the other hand, the present invention can level the surface of the workpiece to be tested while photographing the workpiece to be tested, and use positive pressure to prop up the workpiece to be tested evenly, thereby increasing the accuracy of the detection results.

The present invention has been described in detail above, but the above description is only one of the preferred embodiments of the present invention, and should not limit the scope of the present invention with this, that is, all equivalents made according to the patent scope of the present invention Changes and modifications should still fall within the scope of the patent coverage of the present invention.

100: Optical detection system W: workpiece to be tested 10: Support platform 20: Hollow Structure Vehicle 21: Bearing surface 211: adsorption hole 214: Negative pressure providing device 22: Support surface 23: inner wall 231: Loading surface opening 232: Support surface opening 233: exhaust hole 234: positive pressure supply device 24: Annular outer wall 30: The first image capture device 31: Auxiliary light source 32: Image sensing device 50: Image detection device CB: closed cavity A1: Arrow 200: Optical detection system 40: Second image capturing device 41: Auxiliary light source 42: Image sensing device A2: Arrow A3: Arrow 300: Optical detection system SA: air bearing stage 10A: transparent material plate 20A: Hollow structure carrier 21A: bearing surface 211A: adsorption hole 212A: channel 213A: Through hole 22A: Support surface 23A: Medial wall 231A: exhaust hole 232A: channel 233A: Through hole 24A: Annular outer wall 25A: Round through hole 251A: Loading surface opening 252A: Support surface opening 26A: guide slope 30A: the first image capture device 31A: auxiliary light source 32A: Image sensing device 40A: the second image capture device 41A: auxiliary light source 42A: Image sensing device 50A: Image detection device CB1: closed cavity FA: central air flotation area 400: Optical detection system SB: air bearing platform 10B: Box 20B: Hollow Structure Vehicle 21B: bearing surface 211B: adsorption hole 22B: Support surface 23B: Medial wall 231B: exhaust hole 25B: Round through hole 251B: Loading surface opening 252B: Support surface opening 30B: the first image capture device 31B: Auxiliary light source 32B: Image sensing device 40B: the second image capture device 41B: Auxiliary light source 42B: Image sensing device 50B: Image detection device FB: central air flotation area CB2: closed cavity

Fig. 1 is a schematic block diagram of a single-sided detection embodiment of an optical detection system in the present invention.

Fig. 2 is a schematic block diagram of an embodiment of double-sided detection of the optical detection system in the present invention.

Fig. 3 is a schematic view of the appearance of the first embodiment of the present invention.

Fig. 4 is a schematic side view of the first embodiment of the present invention.

Fig. 5 is a schematic cross-sectional view of the air bearing platform in the first embodiment of the present invention.

Fig. 6 is a top view of the air bearing platform in the first embodiment of the present invention.

Fig. 7 is a schematic view of the appearance of the second embodiment of the present invention.

Fig. 8 is a schematic side view of the second embodiment of the present invention.

Fig. 9 is a schematic cross-sectional view of the air bearing platform in the second embodiment of the present invention.

100: Optical detection system

W: workpiece to be tested

10: Support platform

20: Hollow Structure Vehicle

21: Bearing surface

211: adsorption hole

214: Negative pressure providing device

22: Support surface

23: inner wall

231: Loading surface opening

232: Support surface opening

233: exhaust hole

234: positive pressure supply device

24: Annular outer wall

30: The first image capture device

31: Auxiliary light source

32: Image sensing device

50: Image detection device

CB: closed cavity

A1: Arrow

Claims (11)

An air bearing platform for placing a workpiece to be tested, comprising: a support platform; and A hollow structure carrier is arranged on the support platform, and has a bearing surface and a support surface, so that the workpiece to be measured is carried on the bearing surface, wherein the hollow structure carrier defines a bearing surface through an inner wall surface opening and a supporting surface opening; Wherein the workpiece to be tested, the hollow structural carrier and the supporting platform form a closed cavity; Wherein a plurality of exhaust holes are formed on the inner wall to output air in the closed cavity through a positive pressure supply device to form a central air flotation area. The air bearing platform described in item 1 of the scope of the patent application, wherein a plurality of adsorption holes are formed on the bearing surface to form a peripheral adsorption area, so that the workpiece to be measured is adsorbed on the carrier surface through a negative pressure supply device. bearing surface. The air bearing platform described in item 1 of the scope of the patent application, wherein the support platform includes a transparent material flat plate. The air bearing platform described in item 1 of the scope of the patent application, wherein the inner wall is provided with a guide slope. The air bearing platform described in item 1 of the scope of the patent application, wherein the support platform includes a box body with an accommodation space. An optical detection system for detecting a workpiece to be measured, the system comprising: a support platform; A hollow structure carrier is arranged on the support platform, and has a load surface and a support surface, so that the workpiece to be measured is carried on the load surface, wherein the hollow structure defines an opening of the load surface through an inner wall open with a supporting surface; a first image capturing device, arranged on one side of the supporting surface, for capturing the image of the first surface of the workpiece to be measured; and an image detection device, coupled to the first image capture device, to detect the image of the first surface of the workpiece to be measured; Wherein the workpiece to be tested, the hollow structural carrier and the supporting platform form a closed cavity; Wherein a plurality of exhaust holes are formed on the inner wall to output air in the closed cavity through a positive pressure supply device to form a central air flotation area. The optical inspection system as described in item 6 of the scope of the patent application, wherein a plurality of adsorption holes are formed on the carrier surface to form a peripheral adsorption area, so that the workpiece to be tested is adsorbed on the carrier through a negative pressure supply device face. In the optical inspection system described in item 6 of the scope of the patent application, wherein the supporting platform includes a flat plate made of transparent material, whereby the first image capture device captures the image of the first surface of the workpiece to be tested through the flat plate made of transparent material. The optical inspection system as described in item 6 of the scope of the patent application, wherein the support platform includes a box body with an accommodation space for placing the first image capture device. The optical inspection system as described in item 6 of the scope of the patent application, wherein the first image capture device includes: an auxiliary light source, providing a light source to the first surface of the workpiece to be measured; and An image sensing device is used to obtain the first surface image of the workpiece to be measured. The optical inspection system described in item 6 of the scope of the patent application further includes a second image capture device disposed on one side of the bearing surface to obtain a second image of the workpiece to be inspected.

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