TWI489098B - Defect detection method and defect detection device - Google Patents

Description

Defect detection method and defect detecting device

The present invention relates to a detecting method, and more particularly to a defect detecting method and a defect detecting device for detecting a circuit defect.

Referring to FIG. 1, a conventional defect detecting method is used to detect a circuit board, such as a circuit defect on a glass panel on which a touch circuit is formed. Moreover, since the metal circuit and the ITO line included in the touch circuit have different reflectances to light, the existing defect detection method will be directed to a part of the glass panel, firstly having the first reflectance for the metal line. The light L1 is irradiated, and a first image (image 1) of the region is obtained, and then the second light L2 having a better reflectance for the ITO line is irradiated to obtain a second image (image 2) of the same region. Accordingly, all areas of the glass panel are sequentially scanned to respectively obtain images 1, 2, 3, . . . under the illumination of the first light L1 and the second light L2, and the first light L1 is irradiated. The images 1, 3, 5, which are obtained below are combined, that is, the complete image of the entire glass panel under the illumination of the first light 10, and the images obtained under the illumination of the second light L2 2, 4, 6... are combined to form a complete image of the entire glass panel under the illumination of the second light 20.

Then, you can complete the complete image from the images 1, 3, 5... The defect of the metal line is detected in the image, and the defect of the ITO line is detected from the complete image composed of the images 2, 4, 6 .

However, as shown in FIG. 1, since the first light emitting unit 11 that generates the first light L1 and the second light emitting unit 12 that generates the second light L2 are turned on, it takes a period of charging time TU to reach the preset. When the brightness is completely lit, and it is turned off, it also needs to pass a period of discharge time TD to be completely extinguished. Therefore, if the image capturing time t1 of the images 1, 3, 5, ... covers the charging time TU and the discharging time TD of the first light emitting unit 11, and the image capturing time t2 of the images 2, 4, 6, ... also covers the The charging time TU and the discharging time TD of the two light emitting units 12, the head and tail portions of the images 1, 3, 5, ... and the images 2, 4, 6... will be due to the first light L1 and the second light L2 The brightness of the charging time TU and the discharging time TD is insufficient, or the light mixing phenomenon of the first light L1 and the second light L2 is generated, and the captured content cannot be clearly displayed.

Accordingly, it is an object of the present invention to provide a defect detecting method and a defect detecting device which enable the image of the object to be tested to clearly show the contents of the object to be tested.

Therefore, a defect detecting method of the present invention is for obtaining an image of a test object for defect detection, and comprising: providing a light source to alternately emit a first light and a second light; When the first source of light is emitted by the light source, the image capturing unit is controlled by a controller to obtain the first time interval in which the brightness of the first light is maintained at least half of the first predetermined brightness. a first image of the object to be tested; and when the light source emits the second light, the controller controls the image capturing unit to enable The brightness of the two kinds of light is maintained in a second time interval of at least half of the second predetermined brightness to obtain a second image of the object to be tested.

Furthermore, the invention provides a defect detecting device for implementing the above method, which is used for obtaining an image of a test object for defect detection, and includes a light source, an image capturing unit and a controller; the light source is alternately emitted a first light and a second light; the image capturing unit is configured to obtain an image of the object to be tested; the controller is electrically coupled to the image capturing unit, and emits the first light at the light source And controlling the image capturing unit to obtain a first image of the object to be tested, and acquiring the first image in the first time interval in which the brightness of the first light is maintained at least half of the first predetermined brightness. When the second light is emitted, controlling the image capturing unit to obtain a second image of the object to be tested while maintaining a brightness of the second light at least a half of a second predetermined brightness .

Preferably, the controller further controls the image capturing unit to stop capturing the image in a third time interval between the first time interval and the second time interval, or obtain a third image of the object to be tested.

Preferably, the light source comprises a first light emitting unit that emits the first light and a second light emitting unit that emits the second light.

Preferably, the first lighting unit is turned off, so that when the brightness of the first type of light falls below half of the first predetermined brightness, the controller controls the second lighting unit to be turned on, and the second When the light emitting unit is turned off, such that the brightness of the second light falls below half of the second predetermined brightness, the controller controls the first light emitting unit to be turned on, thereby shortening the third time interval.

Preferably, the first light and the second light are of the same color but different in intensity, or the first light is different from the second light.

Preferably, the image capturing unit is controlled to take image in the first time interval in which the brightness of the first light is maintained at more than 90% of the first predetermined brightness, and the image capturing unit is controlled at The brightness of the second light is maintained in the second time interval of more than ninety percent of the second predetermined brightness.

The present invention controls the image capturing time of the image capturing unit to be maintained in a first time interval in which the brightness of the first light is maintained at least half of the first predetermined brightness, and controls the image capturing time of the image capturing unit in the second The brightness of the light is maintained in a second time interval of at least half of the second predetermined brightness, so that the image capturing unit takes an image when the brightness of the first light and the second light is maintained at least 50% or more. The problem that the head end of the image obtained in the prior art cannot be clearly presented due to insufficient brightness is solved.

1‧‧‧Light source

2‧‧‧Image capture unit

3‧‧‧ Controller

11‧‧‧First lighting unit

12‧‧‧second lighting unit

T1‧‧‧ first time interval

T2‧‧‧ second time interval

T3‧‧‧ third time interval

TU‧‧‧Charging time

TD‧‧‧ discharge time

L1‧‧‧ first light

L2‧‧‧second light

S1~S3‧‧‧ steps

Other features and effects of the present invention will be apparent from the following description of the drawings, wherein: FIG. 1 shows a schematic diagram of a conventional defect detecting method for obtaining an image of a test object; FIG. 2 shows a defect detecting method of the present invention. FIG. 3 is a circuit block diagram of a preferred embodiment of the defect detecting device of the present invention; FIG. 4 shows the first time interval T1 and the second time interval of the present embodiment. T2 obtains a schematic diagram of an image of the object to be tested; FIG. 5 shows a waveform diagram of the first light and the second light of the embodiment; FIG. 6 shows the first time interval T1 and the second time interval T2 of the present embodiment. A schematic diagram of the image of the object to be tested is obtained in the third time interval T3; and FIG. 7 shows a schematic diagram in which the third time interval T3 of the embodiment can be shortened.

Referring to Figures 2 and 3, a preferred embodiment of the defect detecting method of the present invention uses a defect detecting device 100 to obtain an image of a test object (not shown) for defect detection. The defect detecting device 100 mainly includes a light source 1, an image capturing unit 2, and a controller 3 electrically coupled to the light source 1 and the image capturing unit 2.

In order to obtain a clear image of the object to be tested, it is necessary to provide a certain brightness, and in this example, to detect, for example, a circuit defect on a glass panel (subject to be tested) on which a touch circuit is formed, The metal lines and ITO lines included in the control circuit have a large difference in reflectance of light, and cannot be detected by the same light. Therefore, first, as shown in step S1 of FIG. 2, the light source 1 alternately emits a first light L1 and a second light L2 at a predetermined frequency, that is, a so-called stroboflash, the waveform thereof The alternating cycle is shown in Figure 4. Therefore, the light source 1 includes a first light emitting unit 11 that emits the first light L1 and a second light emitting unit 12 that emits the second light L2, wherein the first light L1 has a better reflectivity for the metal line, Two kinds of light L2 has better reflectivity for ITO lines. For example, the first light L1 and the second light L2 are light of the same color but different in intensity, or the first light L1 and the second light L2 are light of different colors.

Of course, if the object to be tested contains a line composed of three or more materials, and the difference in reflectance of the three or more lines is large, three or more different lights (intensities are required) Or the color is different) The object to be measured is taken separately.

In this embodiment, the image capturing unit 2 is a CCD or CMOS image sensor for acquiring an image of the object to be tested. The image capturing unit 2 of the embodiment is an elongated image sensor array, and the light source 1 and the image capturing unit 2 are disposed together and moved at the same time, similar to the scanner, and the image capturing unit 2 is sequentially moved. The object to be tested is sequentially scanned from top to bottom to obtain images of each part of the object to be tested, and further, it is preferably taken by line scan, and the image capturing unit The scanning (taking) frequency of 2 is the same as the preset frequency of the light source 1. However, the foregoing line scan is only an example, and the present invention is not limited thereto.

As shown in FIG. 5, since the first light emitting unit 11 that generates the first light L1 and the second light emitting unit 12 that generates the second light L2 are turned on, it takes a period of charging time TU to reach the preset. When the brightness is completely lit, and it is turned off, it also needs to pass a period of discharge time TD to be completely extinguished.

Therefore, in order to prevent the head and tail portions of the obtained image from being insufficiently displayed due to insufficient brightness of the first light L1 and the second light L2 in the charging time TU and the discharging time TD interval, step S2 and FIG. 4 of FIG. 2 are omitted. Shown When the image capturing unit 2 sequentially scans the object to be tested, the controller 3 controls the brightness of the first light L1 of the image capturing unit 2 to reach a first preset each time the light source 1 emits the first light L1. A first time interval T1 of at least half of the brightness obtains a first image of the object under the first light L1, that is, images 1, 3, 5, .

As shown in step S3 of FIG. 2, the controller 3 controls the image capturing unit 2 to achieve at least a second predetermined brightness of the second light L2 when the light source 1 emits the second light L2. More than half of the second time interval T2 obtains a second image of the object under the second light L2, that is, images 2, 4, 6, . Thereby, the image capturing unit 2 is controlled to take images when the brightness of the first light L1 and the second light L2 is maintained at least 50% or more, so as to solve the problem that the head and tail ends of the image obtained in the prior art are insufficient in brightness. It is impossible to clearly present the problem.

When the first light L1 and the second light L2 are light of the same color but different in intensity, the first preset brightness (the preferred reflectance to the metal line) is smaller than the second preset brightness (for the ITO line) Good reflectance), and if the first light L1 and the second light L2 are different colors of light, the first preset brightness (for metal lines) can be compared with the second preset brightness according to actual application requirements (for ITO lines) are the same or different. Further, if the first light L1 and the second light L2 are light of the same color but different in intensity, it is also possible to alternately emit light of different intensities using only a single light-emitting unit.

Preferably, in the embodiment, the image capturing unit 2 is to be measured in the first time interval T1 when the brightness of the first light L1 is maintained at (or reaches) 90% of the first predetermined brightness. Taking images (photographing), and The object to be measured is imaged in a second time interval T2 in which the brightness of the second light L2 is maintained at (or reaches) 90% of the second predetermined brightness, but in the first time interval T1 and the second time interval a third time interval T3 between the time interval T2 (including the discharge time TD of the first light L1 and the charging time TU of the second light L2, or the charging time TU and the second light including the first light L1) The discharge time TD of L2 is not taken. Thereby, the imaging time of the image capturing unit 2 is completely avoided by the charging time TU and the discharging time TD interval of the first light L1 and the second light L2, thereby solving the problem that the head and tail ends of the image obtained in the prior art cannot be Clearly present the problem and have almost the same image quality at the head and tail of the resulting image and the middle portion of the image.

Finally, in the subsequent processing, the images 1, 3, 5, ... obtained under the illumination of the first light L1 are combined, that is, the entire object to be tested (glass panel) is irradiated under the first light L1. a complete image, and the images 2, 4, 6... obtained under the illumination of the second light L2 are combined, that is, the complete image of the entire object to be tested (glass panel) under the illumination of the second light 20 .

Then, the defects of the metal line can be detected from the complete image composed of the images 1, 3, 5, ..., and the defects of the ITO line are detected from the complete image composed of the images 2, 4, 6 .

Referring to FIG. 6 again, another embodiment of the present embodiment is that the controller 3 controls the image capturing unit 2 to continuously take images, that is, control the image capturing unit 2 except for the first time interval T1 of the first type of light L1. The second time interval T2 of the second light L2 is taken out of the image, and is also taken in the third time interval T3 between the first time interval T1 and the second time interval T2, so in this embodiment Next, the image capturing unit 2 sequentially acquires the images 1, 2, 3, . . . , so the scanning (taking) frequency of the image capturing unit 2 is twice the preset frequency of the light source 1.

Then, in the subsequent processing, the images 1, 5, ... obtained in each of the first time intervals T1 are combined to form a complete image of the object (glass panel) under the illumination of the first light L1. And combining the images 3, 7, and ... obtained in each of the second time intervals T2 to form a complete image of the object to be tested (glass panel) under the illumination of the second light L2, and at each third time The images 2, 4, 6... obtained in the interval T3 are discarded.

Referring again to FIG. 7, the controller 3 of the present embodiment is further electrically coupled to the light source 1 and is turned off at the first light emitting unit 11, so that the brightness of the first light L1 is lowered to half of the first predetermined brightness. In the following, the controller 3 controls the second lighting unit 12 to be turned on, and when the second lighting unit 12 is turned off, so that the brightness of the second light L2 falls below half of the second predetermined brightness, the controller 3 Controlling that the first light emitting unit 11 is turned on, thereby overlapping the discharge time TD of the first light L1 with the charging time TU of the second light L2, and making the discharge time TD of the second light L2 and the first light L1 The charging time TU overlaps to shorten the third time interval T3, thereby improving the scanning (taking) efficiency of the image capturing unit 2.

In summary, the above embodiment maintains the brightness of the first type of light L1 at least half of the first predetermined brightness by controlling the image capturing time of the image capturing unit 2, for example, the first of 90% or more. The time interval, and the image capturing time of the control image taking unit are maintained at at least half of the second predetermined brightness in the second light L2, for example, a second time of more than 90% The interval is such that the image capturing unit 2 takes an image when the brightness of the first light L1 and the second light L2 is maintained at least 50% or more, thereby solving the brightness of the head and tail of the image obtained in the prior art. The problem that is insufficient and cannot be clearly presented achieves the efficacy and purpose of the present invention.

The above is only the preferred embodiment of the present invention, and the scope of the present invention is not limited thereto, that is, the simple equivalent changes and modifications made by the patent application scope and patent specification content of the present invention, All remain within the scope of the invention patent.

S1~S3‧‧‧ steps

Claims (10)

A defect detecting method for obtaining an image of a test object for detecting a defect thereof, comprising: providing a light source to alternately emit a first light and a second light; when the light source sends out In the first type of light, an image capturing unit is controlled by a controller, and when the brightness of the first light is maintained at a first time interval of at least half of the first predetermined brightness, the object to be tested is obtained. a first image; and when the light source emits the second light, the controller controls the image capturing unit to maintain a brightness of the second light at least half of a second predetermined brightness In the second time interval, a second image of the object to be tested is obtained. The defect detecting method of claim 1, wherein the controller further controls the image capturing unit to stop capturing the image in a third time interval between the first time interval and the second time interval, or obtain the to-be-tested a third image of the object. The defect detecting method of claim 2, wherein the light source comprises a first light emitting unit that emits the first light and a second light emitting unit that emits the second light. The defect detecting method of claim 3, wherein the controller controls the second when the first lighting unit is turned off such that the brightness of the first type of light falls below half of the first predetermined brightness The light emitting unit is turned on, and when the second light emitting unit is turned off, the second light is turned on The controller controls the first lighting unit to be turned on when the brightness falls below half of the second predetermined brightness, thereby shortening the third time interval. The defect detecting method of claim 1, wherein the image capturing unit is controlled to take image in the first time interval in which the brightness of the first light is maintained at more than 90% of the first predetermined brightness. And the image capturing unit is controlled to take image in the second time interval in which the brightness of the second light is maintained at more than ninety percent of the second predetermined brightness. A defect detecting device is configured to obtain an image of a test object for defect detection, and includes: a light source alternately emitting a first light and a second light; and an image capturing unit for obtaining An image of the object to be tested; and a controller electrically coupled to the image capturing unit, and controlling the brightness of the image capturing unit to be maintained at the first light when the light source emits the first light Acquiring a first image of the object to be tested at a first time interval of at least half of the first predetermined brightness, and controlling the image capturing unit at the second when the light source emits the second light The brightness of the light is maintained in a second time interval of at least half of the second predetermined brightness to obtain a second image of the object to be tested. The defect detecting device of claim 6, wherein the controller further controls the image capturing unit to stop capturing the image in a third time interval between the first time interval and the second time interval, or obtain the to-be-tested a third image of the object. The defect detecting device of claim 7, wherein the light source comprises a hair a first light emitting unit of the first light and a second light emitting unit emitting the second light. The defect detecting device of claim 8, wherein the first lighting unit is turned off, such that when the brightness of the first type of light falls below half of the first predetermined brightness, the controller controls the second lighting When the unit is turned on, and the second light emitting unit is turned off, such that the brightness of the second light falls below half of the second predetermined brightness, the controller controls the first light emitting unit to be turned on, thereby shortening The third time interval. The defect detecting device of claim 6, wherein the image capturing unit is controlled to capture the first time interval in which the brightness of the first type of light is maintained at more than ninety percent of the first predetermined brightness. And the image capturing unit is controlled to take image in the second time interval in which the brightness of the second light is maintained at more than ninety percent of the second predetermined brightness.