TWI726504B - Apparatus for inspecting cover glass - Google Patents

Abstract

The invention relates to a glass cover inspection device. The first imaging device is positioned above the glass cover as the inspection object, descends in step units from the origin and obtains an image of the glass cover. The second imaging device and the first imaging device are descended in step units and simultaneously obtain an image of the glass cover. The controller detects the top position of the glass cover based on the image information obtained by the second camera device, and detects the top position of the glass cover based on the detected top position information of the glass cover and the image information obtained by the first camera device. Bad location, from which it is determined whether there is a bad authenticity.

Description

Glass cover inspection device

The present invention relates to a technique for inspecting defects of glass covers used in smartphones and the like.

The glass cover is a product located on the outermost side of the screen in order to protect the screen of a smartphone, etc. from impact and scratches. For smart phones, the glass cover is located on the outermost side of the smart phone screen to protect the smart phone's display and touch panel.

On the other hand, if there is a defect caused by foreign matter on the glass cover, the view of the screen will be obstructed due to the defect, and the visibility of the screen can be reduced. When the glass cover is composed of multiple layers (multi-layer), the defects are not only located on the surface of the glass cover, but also located inside the glass cover.

Since the surface defects of the glass cover plate can be easily repaired by surface processing or the like, it can be classified as false defects, and because the internal defects of the glass cover plate cannot be repaired, it can be classified as authenticity defects. Therefore, when the glass cover is inspected for defects, it is necessary to confirm the position of the defect to determine whether there is an authenticity defect.

technical problem

The problem of the present invention is to provide a glass cover inspection device that can improve the accuracy of the inspection by determining whether there is an authenticity defect when performing a defect inspection on a glass cover. Solution to the problem

The glass cover inspection device of the present invention for achieving the above-mentioned problems includes a first camera device, a second camera device, and a controller. The first imaging device is positioned above the glass cover as the inspection object, descends in step units from the origin and obtains an image of the glass cover. The second imaging device and the first imaging device are descended in step units and simultaneously obtain an image of the glass cover. The controller detects the top position of the glass cover based on the image information obtained by the second camera device, and detects the top position of the glass cover based on the detected top position information of the glass cover and the image information obtained by the first camera device. Bad location to determine whether there is a bad authenticity.

Among them, the controller marks the serial number according to the image obtained by the first camera device, and can subtract the image serial number obtained at the top position of the glass cover from the image serial number with the highest definition of the defective part of the glass cover The value is multiplied by the step value to detect the bad position.

The first imaging device may include: a first illuminator that illuminates the glass cover above the glass cover; and a first camera that obtains an image of the glass cover illuminated by the first illuminator. The second imaging device may include: a second illuminator that illuminates the glass cover on the side of the glass cover; and a second camera that obtains an image of the glass cover illuminated by the second illuminator. The effect of the invention

According to the present invention, when performing a defect inspection on a glass cover, it is determined whether there is a genuine defect or a false defect, and the types of defects can be classified, so that the accuracy of the inspection of the glass cover can be improved.

With reference to the drawings, the present invention will be described in detail as follows. Here, the same reference numerals are used for the same structure, and repeated descriptions or detailed descriptions of well-known functions and structures that may make the gist of the present invention unclear are omitted. The embodiments of the present invention are provided for a more complete description of the present invention for those of ordinary skill in the art. Therefore, the shapes and sizes of the structural elements in the drawings may be exaggerated for clearer description.

Fig. 1 is a structural diagram of a glass cover inspection device according to an embodiment of the present invention. FIG. 2 is a diagram showing a standby state of the first imaging device and the second imaging device at the origin position. 3 is a diagram showing a detection state in which the second imaging device is lowered to detect the tip position of the glass cover. Fig. 4 is a diagram showing a detection state in which the first imaging device is lowered to detect a defective position of the glass cover. Fig. 5 is a diagram showing images obtained by the first imaging device at each position in Figs. 2 to 4. FIG. 6 is a diagram showing images obtained by the second imaging device at each position in FIGS. 2 to 4.

1 to 6, the glass cover inspection apparatus 100 according to an embodiment of the present invention includes a first camera device 110, a second camera device 120 and a controller 130.

The first imaging device 110 is above the glass cover 10 that is the inspection object, descends in step units from the origin, and obtains an image of the glass cover 10. As shown in FIG. 5, the first imaging device 110 descends in step units from above the defective part 11 of the glass cover 10 to obtain the most perfect focused image for the defective part 11 of the glass cover 10, that is, to obtain the highest definition The image can be provided to the controller 130.

The glass cover 10 is in a positioned state on the horizontal surface of the table 101, and the first camera device 110 can perform the lifting action according to the lifting device 102. The first imaging device 110 descends from the origin in step units according to the state where the lifting device 102 rises to the origin, and can obtain an image of the glass cover 10.

Wherein, the step value may be much larger than the depth of focus of the first imaging device 110. The depth of focus is the range that can be moved in focus when the position of the object is changed according to the optical axis of the lens, and refers to the distance at which a clear image can be captured. Therefore, the first imaging device 110 can obtain an image focused on the defective part 11 of the glass cover 10 according to different steps. The bottom dead center of the first imaging device 110 can be set to obtain an image of the bottom end of the glass cover plate 10.

The lifting device 102 may be constituted by a linear actuator such as a piezoelectric actuator. The table top 101 is moved horizontally according to a horizontal movement tool (not shown), and thereby the glass cover 10 can be moved horizontally. Therefore, the first imaging device 110 scans the glass cover 10 while performing a horizontal relative movement, so that defective parts of the glass cover 10 can be detected in advance. Of course, the first camera device 110 can also move horizontally when the table top 101 is in a positioning state.

As an example, the first imaging device 110 may include: a first illuminator 111 to illuminate the glass cover 10 from above the glass cover 10; and a first camera 116 to obtain the glass illuminated by the first illuminator 111 The image of the cover plate 10.

The first illuminator 111 may include a light source 112, a mirror 113a, and a beam splitter 113b. The light source 112 may be composed of an LED (light emitting diode). The light source 112 may be arranged on the upper surface of the glass cover 10 so as to irradiate light in a vertical direction. The mirror 113a transmits the light emitted from the light source 112 to the beam splitter 113b. The beam splitter 113 b reflects light, illuminates the glass cover 10 from above, and transmits the light reflected from the glass cover 10 to the first camera 116.

The first imaging device 110 may transmit the light reflected from the glass cover plate 10 to the first camera 116 via an objective lens 114 and a tube lens 115. The objective lens 114 is composed of an objective lens for near-infrared rays, and can compensate for chromatic aberrations from the visible light band to the near-infrared wavelength band. The tube lens 115 can determine the magnification together with the objective lens 114 and compensate for chromatic aberration. For example, the tube lens 115 may have 0.75 magnification, and the objective lens 114 may have 10 magnification. That is, the first imaging device 110 includes a microscope optical system, and image information of the defective portion 11 of the glass cover 10 can be obtained.

The second camera device 120 and the first camera device 110 are descended in a step unit and simultaneously obtain an image of the glass cover 10. As shown in FIG. 6, the second camera device 120 descends in step units and can provide the top position information of the glass cover 10 to the controller 130. The second camera device 120 is fixed to the lifting support body together with the first camera device 110, and can perform lifting actions according to the lifting device 102.

For example, the second camera device 120 may include: a second illuminator 121 to illuminate the glass cover 10 from the side of the glass cover 10; and a second camera 126 to obtain the glass illuminated by the second illuminator 121 The image of the cover plate 10. The second illuminator 121 can irradiate light at an inclination angle with respect to the upper surface of the glass cover plate 10. The second illuminator 121 includes a laser light source or an LED light source, and can illuminate light in the form of a linear beam. That is, the second imaging device 120 includes an optical triangulation optical system, and the tip position information of the glass cover plate 10 can be obtained.

The controller 130 detects the top position of the glass cover 10 based on the image information obtained by the second imaging device 120, and based on the detected top position information of the glass cover 10 and the image information obtained by the first imaging device 110, The defective position of the glass cover plate 10 is detected to determine whether there is a defective authenticity.

For example, the controller 130 marks the serial number according to the image obtained by the first imaging device 110, and may subtract the image number at the top of the glass cover 10 from the image serial number with the highest resolution for the defective part of the glass cover 10 The value obtained from the image number is multiplied by the step value to detect the defective position.

That is, the controller 130 can detect the defective position of the glass cover based on the position of the top end of the glass cover 10 according to the following formula 1. [Math 1]

Bad position = Nth image sequence number x step value

Among them, the Nth image serial number corresponds to the serial number sequentially numbered from the image obtained from the top position of the glass cover 10 to the image with the highest resolution from the defective part 11 of the glass cover 10.

In the process of the second camera device 120 descending in step units to obtain the image of the glass cover plate 10, the controller 130 may transfer the image from the second illuminator 121 through the glass cover plate 10 as shown in (b) of FIG. The starting position of the reflected light sensed by the setting area of the second camera 126 is determined as the top position of the glass cover 10. The setting area of the second camera 126 may be equivalent to the central area of the shooting part of the second camera 126, but is not limited to the illustrated content. The controller 130 can store the image serial number obtained according to the first camera device 110 in the memory at the top position of the glass cover 10.

In the process of the first imaging device 110 descending in step units and obtaining the image of the glass cover plate 10, the controller 130 selects the defect portion 11 of the glass cover plate 10 with the highest definition as shown in FIG. 5(c) Image, its image serial number can be stored in the memory.

Among them, the controller 130 uses edge-based methods that measure the degree of spread of edges in space to estimate sharpness, or uses frequency-based methods that measure frequency distribution to estimate sharpness (spectral-based methods). based methods), etc., comparing multiple images obtained by the first imaging device 110 for each step, so that the image with the highest definition of the defective part 11 of the glass cover 10 can be selected.

Therefore, the controller 130 can detect the defective position of the glass cover plate 10 according to the above-mentioned Mathematical Formula 1. If the controller 130 determines that the detected defective position is located between the top end and the bottom end of the glass cover 10, that is, is located inside the glass cover 10, it is determined that the authenticity is poor. If the controller 130 determines that the detected defect position is located at the top or bottom end of the glass cover 10, that is, on the surface of the glass cover 10, it is determined as a false defect.

The method of inspecting the defects of the glass cover plate 10 according to the aforementioned glass cover plate inspection device 100 will be described as follows.

First, as shown in FIG. 2, the first imaging device 110 scans the horizontal relative movement of the glass cover 10 at the height of the origin, so that the defective part 11 of the glass cover 10 can be detected in advance. At this time, the controller 130 compares the image obtained by scanning by the first imaging device 110 with the reference image, so that the defective portion 11 of the glass cover 10 can be detected.

If the defective part 11 of the glass cover 10 is detected, the first imaging device 110, as shown in FIG. 3, is above the defective part 11 of the glass cover 10 and descends in step units from the origin to obtain the glass cover 10 Of the image. At the same time, the second camera device 120 and the first camera device 110 descend in step units and obtain an image of the glass cover 10.

In this process, the controller 130 detects the top position of the glass cover plate 10 based on the image information obtained by the second camera device 120. At this time, as shown in FIG. 6(b), the controller 130 may determine the starting point of the light reflected from the second illuminator 121 via the glass cover plate 10 to be sensed by the set area of the second camera 126 as the glass cover The top position of the plate 10 can store the image serial number obtained by the first camera device 110 in the memory at the top position of the glass cover 10.

As shown in FIG. 4, the first camera device 110 continues to descend in step units and obtains an image of the glass cover plate 10. The first camera device 110 is lowered to the bottom end position of the glass cover 10 to obtain an image of the glass cover 10. In this process, the controller 130 can select the image with the highest definition of the defective part 11 of the glass cover 10. At this time, as shown in FIG. 5(c), the controller 130 can store the image number with the highest resolution of the defective part 11 of the glass cover 10 in the memory.

Next, the controller 130 reads the image serial number with the highest resolution of the defective part 11 of the glass cover 10 and the image serial number obtained at the top position of the glass cover 10 from the memory, and can retrieve the defective part 11 of the glass cover 10 from the memory. A value obtained by subtracting the image number obtained at the top position of the glass cover 10 from the image number with the highest resolution of the part 11 is multiplied by the step value to detect the defective position.

Next, if the controller 130 determines that the detected defective position is located between the top and bottom ends of the glass cover 10, that is, is located inside the glass cover 10, it is determined to be a bad authenticity. If the controller 130 determines that the detected defect position is located at the top or bottom end of the glass cover 10, that is, on the surface of the glass cover 10, it is determined as a false defect.

As described above, when the glass cover inspection device 100 performs a defect inspection on the glass cover 10, it is determined whether there is a genuine defect or a false defect, and the types of defects can be classified. Therefore, the inspection accuracy of the glass cover 10 can be improved.

Although the present invention is described with reference to an embodiment shown in the accompanying drawings, this is only illustrative. As long as a person of ordinary skill in the art to which the present invention belongs, it should be understood that various modifications and other equivalent implementations can be realized. example. Therefore, the true protection scope of the present invention should only be defined by the appended patent scope.

10: Glass cover 11: Bad parts 100: Glass cover inspection device 101: Countertop 102: Lifting equipment 110: The first camera equipment 111: The first illuminator 112: light source 113a: Mirror 113b: beam splitter 114: Objective 115: tube lens 116: The first camera 120: second camera equipment 121: second illuminator 126: second camera 130: Controller

Fig. 1 is a structural diagram of a glass cover inspection device according to an embodiment of the present invention. FIG. 2 is a diagram showing a standby state of the first imaging device and the second imaging device at the origin position. 3 is a diagram showing a detection state in which the second imaging device is lowered to detect the tip position of the glass cover. Fig. 4 is a diagram showing a detection state in which the first imaging device is lowered to detect a defective position of the glass cover. Fig. 5 is a diagram showing images obtained by the first imaging device at each position in Figs. 2 to 4. FIG. 6 is a diagram showing images obtained by the second imaging device at each position in FIGS. 2 to 4.

10: Glass cover

11: Bad parts

100: Glass cover inspection device

101: Countertop

102: Lifting equipment

110: The first camera equipment

111: The first illuminator

112: light source

113a: Mirror

113b: beam splitter

114: Objective

115: tube lens

116: The first camera

120: second camera equipment

121: second illuminator

126: second camera

130: Controller

Claims (2)

A glass cover inspection device, which is characterized by comprising: a first camera device, above the glass cover as the inspection object, descends in step units from the origin to obtain an image of the glass cover; second An imaging device that obtains an image of the glass cover while descending in step units together with the first imaging device; and a controller that detects the glass cover based on the image information obtained by the second imaging device The top position of the plate, based on the detected top position information of the glass cover and the image information obtained by the first imaging device, to detect the defective position of the glass cover to determine whether there is a bad authenticity, wherein , The controller marks the serial number according to the image obtained by the first imaging device, and subtracts all the images on the glass cover from the image serial number with the highest definition of the defective part of the glass cover. The value obtained from the image sequence number obtained at the top position is multiplied by the step value to detect the defective position. The glass cover inspection device according to claim 1, wherein the first imaging device includes: a first illuminator that illuminates the glass cover above the glass cover; and a first camera , Obtaining the image of the glass cover illuminated by the first illuminator; and the second imaging device includes: a second illuminator, on the side of the glass cover, facing the glass The cover plate is illuminated; and a second camera to obtain the image of the glass cover plate illuminated by the second illuminator.

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