KR102132673B1 - Ultrasonic waterfall type water layer equalizing apparatus for inspection of OLED panel - Google Patents

Abstract

When inspecting the bubbles inside the OLED panel using the ultrasonic waterfall non-destructive test, the ultrasonic waterfall method is used to equalize the water layer to improve the accuracy of the inspection of the OLED panel. As a related art, an oil film forming unit that flows water to an inspection object to form an oil film, an ultrasonic wave is transmitted to an inspection object on which an oil film is formed, and a bubble detection unit and bubbles that output a signal reflected by a density difference between the inspection objects as a bubble detection signal Including an image processor that converts the bubble detection signal detected by the detector into an image, implements an oil film equalization device when inspecting an OLED panel using an ultrasonic waterfall method.

Description

{Ultrasonic waterfall type water layer equalizing apparatus for inspection of OLED panel}

The present invention relates to an equalization device for a water layer when inspecting an OLED (Organic Light Emitting Diodes) panel using an ultrasonic waterfall method, and more particularly, bubbles inside the OLED panel using ultrasonic waterfall non-destructive testing. When inspecting the, it relates to an oil film equalization device when inspecting an OLED panel using an ultrasonic waterfall method that equalizes the water layer to promote accuracy in inspecting the OLED panel.

Among the display devices, the organic light emitting display (OLED) device has attracted attention as a next-generation display device because it has a wide viewing angle, excellent contrast, and a fast response speed.

A display panel such as an organic light emitting display device may generate various types of defects during manufacture, and foreign matter or smear (stain) and surface scratches and bubbles on the display panel adversely affect the performance of the display, so it is thoroughly detected through pre-inspection. / Should be removed.

In particular, it is not possible to detect in advance that air bubbles have occurred in the OLED panel, and when manufacturing a display device using this, a defect occurs and causes a very large loss. Therefore, air bubbles in the OLED panel are detected before manufacturing the display device. It is very important to do.

In general, the display panel inspection method mainly uses a macro inspection method that detects foreign substances or the like by the naked eye, and a micro inspection method that precisely finds a defective state using a microscope.

However, there is a disadvantage in that the visual inspection is inferior in precision and the microscopic inspection takes a lot of inspection time, and new inspection methods are required.

On the other hand, conventional techniques for the inspection method of the display panel are disclosed in <Patent Documents 1> to <Patent Documents> below.

The prior art disclosed in <Patent Document 1> uses a 3D sensor formed to face the first surface of the display panel, and an image acquisition unit formed to face the second surface of the display panel, and thus the defects of the first surface and the second surface. It provides a display panel inspection apparatus and a display panel inspection method capable of simultaneously inspecting.

In addition, the prior art disclosed in <Patent Document 2> uses a camera for foreign material shooting, divides the thickness of the flat panel display panel into a plurality of heights, and then aligns the focus of the camera on each center line of the divided plurality of heights. By photographing, it is possible to clearly photograph a photographed image of a foreign substance regardless of the thickness in the vertical direction of the foreign substance, thereby inspecting the foreign substances in the flat panel display panel.

In addition, in the prior art disclosed in <Patent Document 3>, a turntable capable of supporting a panel for transmitting a light that can transmit light, a turntable rotating unit for rotating the turntable, a plurality of backlights disposed on an upper surface of the turntable, and installed on a turntable Power supply unit for supplying power to a plurality of backlights, a plurality of transmissive panel inspection cameras, a plurality of transmissive panel inspection cameras to move each of the transmissive panel inspection cameras so that each of the transmissive panel inspection cameras can sequentially photograph various parts of the panel for the transmissive display Transmissive Panel Inspection Camera Implements an inspection device for a display panel, including a mobile unit, a control unit that receives a captured image from a plurality of transparent panel inspection cameras, analyzes it, and controls the overall operation of the device.

Through such a configuration, there is provided an inspection device for a display panel that can continuously and quickly inspect various display panels.

In addition, the prior art disclosed in <Patent Document 4> is a panel seating table having a plurality of panel seating portions through which light can pass, a table rotating device for rotating the panel seating table, and an inspection for obtaining an image of a panel for light transmissive display. By using a camera, a panel for various light transmissive displays is continuously and rapidly inspected.

Republic of Korea Registered Patent 10-1584767 (announced on December 12, 2016) (display panel inspection device and display panel inspection method) Republic of Korea Registered Patent 10-1789651 (Announcement of October 25, 2017) (Foreign material inspection method of flat panel display panel) Republic of Korea Registered Patent 10-1146721 (announced on May 17, 2012) (inspection device for display panels) Republic of Korea Registered Patent 10-1146722 (announced on May 17, 2012) (inspection device for display panels)

However, the above prior arts are a method of inspecting a display panel using a vision device such as a camera, and it is possible to externally inspect the OLED panel with a vision camera, but there is a limitation in inspecting the bubbles inside.

Therefore, in recent years, as another method of inspecting bubbles inside the OLED panel, a method of detecting bubbles by an ultrasonic method using an ultrasonic probe has also been proposed.

In the method of inspecting the OLED panel using ultrasonic waves in a non-destructive manner, water flows to the inspection object (OLED panel), ultrasonic waves are transmitted to the inspection object through which the water is flowed using a transducer, an ultrasonic probe, and the density of the inspection object After detecting the signal reflected by the vehicle as a bubble detection signal, a method of converting and displaying the bubble detection signal detected through the image processor into an image is used.

In the case of inspecting the bubbles of the OLED panel using the ultrasonic probe transducer, the ultrasonic waves do not reach the inspection object if there is air between the transducer (probe) and the inspection object. Therefore, it is very important to form a water layer without air bubbles. However, the proposed method of forming an oil film without air bubbles is not provided in the proposed ultrasonic type OLED panel inspection apparatus, and thus the reliability of the inspection equipment is deteriorated.

Therefore, the present invention has been proposed to solve various problems occurring in the prior art as described above, and when inspecting the bubbles inside the OLED panel using ultrasonic waterfall non-destructive inspection, the water layer is equalized to make the OLED panel The purpose of the present invention is to provide an oil film equalization device for inspection of an OLED panel using an ultrasonic waterfall method to promote accuracy in inspection.

Another object of the present invention, when examining the bubbles inside the OLED panel using the ultrasonic waterfall non-destructive inspection, by forming an oil layer (water layer) without air bubbles (Air), the ultrasonic waterfall to promote the accuracy of the inspection of the OLED panel In this way, it is to provide an oil film equalization device when inspecting an OLED panel.

In order to achieve the object as described above, when inspecting an OLED panel by an ultrasonic waterfall method according to the present invention, an oil film equalization device includes: an oil film forming unit that flows water to an inspection object to form an oil film; A bubble detection unit that transmits ultrasonic waves to the inspection object on which the oil film is formed, and outputs a signal reflected by the density difference of the inspection object as a bubble detection signal; And an image processor that converts the bubble detection signal detected by the bubble detection unit into an image.

The object to be inspected in the above is characterized in that it is a liquid crystal display panel or an OLED (Organic Light Emitting Diodes) panel.

In the above, the oil film forming part has a circular body having a space therein; First and second water supply pipes which are installed opposite to one end of the body and have a space formed therein to supply water; A first vortex prevention jaw to prevent water from being supplied through the first water supply pipe rapidly and colliding with water supplied through the second water supply pipe to generate vortex; A second vortex prevention jaw to prevent water bubbles caused by vortex from colliding with the water supplied through the first water supply pipe by rapidly supplying water supplied through the second water supply pipe; It is characterized in that it comprises a hole formed in the lower portion of the body to form an oil film on the inspection object by discharging the water passing through the first vortex prevention jaw and the second vortex prevention jaw downward.

In the above, it is characterized in that a plurality of oil film forming holes are formed to form an even oil film at a small flow rate.

In the above, the oil film forming unit further includes first and second flow sensors for detecting the amount of water supplied through the first and second water supply pipes.

In addition, the oil film equalization device when inspecting an OLED panel using the ultrasonic waterfall method according to the present invention further comprises a manual stage that moves the bubble detection unit up and down to adjust the distance between the probe (transducer) and the inspection object. It is characterized by including.

In the above, the manual stage includes distance adjusting means for adjusting the distance between the probe and the inspection object by controlling the vertical movement of the bubble detection unit according to the flow rate detected through the first and second flow sensors built in the oil film forming unit. It is characterized by.

In the above, the distance adjusting means compares the detected flow rate with the reference flow rate, and controls the transport of the bubble detection unit so that the distance between the water guide and the transducer increases when the detected flow rate is greater than the reference flow rate, and the detected flow rate is the reference flow rate. When the flow rate is smaller than the flow rate, it is characterized in that the bubble detection unit is controlled to control the distance between the water guide and the transducer.

According to the present invention, when inspecting the bubbles inside the OLED panel using the ultrasonic waterfall non-destructive inspection, there is an effect that the water layer is equalized to improve the accuracy of the inspection of the OLED panel.

In addition, according to the present invention, when inspecting the bubbles inside the OLED panel using the ultrasonic waterfall non-destructive inspection, there is also an effect of forming an oil layer without air (air) to promote accuracy in the inspection of the OLED panel.

1 is a schematic diagram of an oil film equalization device when inspecting an OLED panel using an ultrasonic waterfall method according to the present invention;
2 is a perspective view of an oil film equalization device when inspecting an OLED panel using an ultrasonic waterfall method according to the present invention;
3 is a bottom view of an oil film equalization device when inspecting an OLED panel using an ultrasonic waterfall method according to the present invention;
4 is a partial cross-sectional view of an oil film equalization device when inspecting an OLED panel using an ultrasonic waterfall method according to the present invention;
Figure 5 is an explanatory diagram of the distance between the inspection object and the transducer in the present invention,
FIG. 6 is an exemplary view of an image according to a distance between a water guide and a transducer compared to an amount of water supplied.

Hereinafter, an oil film equalization device when inspecting an OLED panel using an ultrasonic waterfall method according to a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

1 is a configuration diagram of an oil film equalization device when inspecting an OLED panel by an ultrasonic waterfall method according to a preferred embodiment of the present invention, and FIG. 2 is an oil film equalization device when inspecting an OLED panel by an ultrasonic waterfall method according to the present invention 3 is a bottom view of an oil film equalization device when inspecting an OLED panel with an ultrasonic waterfall method according to the present invention, and FIG. 4 is a part of an oil film equalization device when inspecting an OLED panel with an ultrasonic waterfall method according to the present invention It is a cross section.

When inspecting an OLED panel by the ultrasonic waterfall method according to the present invention, the oil film equalization device flows water on the inspection object (OLED panel or liquid crystal display panel) 10 to form an oil film 20, the oil film Bubble detection unit 30 that transmits ultrasonic waves to the formed inspection object 10 and outputs a signal reflected by the density difference of the inspection object 10 as a bubble detection signal, detects bubbles detected by the bubble detection unit 30 An image processor 40 for converting a signal into an image, and a manual stage 50 for adjusting the distance between the probe (transducer) 31 and the inspection target 10 by moving the bubble detector 30 up and down ).

The oil film forming unit 20 is a circular body 24 having a space formed therein, and is installed opposite to one end of the body 24, and spaces 21b and 22b are formed therein to supply water. And second water supply pipes 21 and 22, and water supplied through the first water supply pipe 21 is rapidly supplied to collide with water supplied through the second water supply pipe 22 to generate vortex. The first vortex prevention jaw (21a) to prevent the, water supplied through the second water supply pipe 22 is suddenly supplied and collides with the water supplied through the first water supply pipe (21) to cause bubbles caused by vortex The second vortex prevention jaw 22a, which is prevented from being generated, is formed on the lower portion of the body 24, and discharges water that has passed through the first vortex prevention jaw 21a and the second vortex prevention jaw 22a downward to be inspected. (10) includes an oil film forming hole 23 for forming an oil film. Here, it is preferable that a plurality of oil film forming holes 23 are formed to form an even oil film at a small flow rate.

In addition, the oil film forming unit 20 may include first and second flow sensors 21c and 22c that detect the amount of water supplied through the first and second water supply pipes 21 and 22. have.

In addition, the bubble detection unit 30 generates an ultrasonic pulse, and transmits the ultrasonic wave generated from the pulse/receiver 32 and the pulse/receiver 32 that converts the reflected ultrasonic signal into an electrical signal to the inspection target 10 Then, a probe 31 that receives the signal reflected from the inspection object 10 and transmits it to the pulse/receiver 32, and converts the electrical signal received from the pulse/receiver 32 into a digital signal. It includes an analog-to-digital converter 33 to deliver to the image processor 40.

Here, the probe 31 may be embodied as various devices for transmitting ultrasonic waves and receiving reflected ultrasonic signals, but in the present invention, ultrasonic waves are transmitted to the inspection object 10 and signals reflected from the inspection object 10 are reflected. It will be described as an example of using a transducer that receives and converts it into an electrical signal.

In addition, the manual stage 50 controls the vertical movement of the bubble detection unit 30 according to the flow rates detected through the first and second flow sensors 21c and 22c built in the oil film forming unit 20. It includes a distance adjusting means for adjusting the distance between the probe 31 and the inspection object (10). Here, the distance adjusting means compares the detected flow rate with the reference flow rate, controls the transport of the bubble detection unit 30 so that the distance between the water guide and the transducer increases when the detected flow rate is greater than the reference flow rate, and the detected flow rate is When it is smaller than the reference flow rate, the transport of the bubble detection unit 30 is controlled so that the distance between the water guide and the transducer is reduced.

In addition, the image processor 40 is an image converter that converts the bubble detection signal detected by the bubble detection unit 30 into an image, and a display unit that displays bubble generation information by displaying the image signal converted by the image converter on a screen. And, it may include a bubble detection unit that analyzes the pixel color information of the unit image image converted by the image converter to determine the presence or absence of bubbles detection, and a bubble detection alarm unit that alerts when bubbles are detected in the bubble determination unit.

The operation of the oil film equalization device when inspecting the OLED panel by the ultrasonic waterfall method according to the present invention configured as described above will be described in detail as follows.

First, in the state where the OLED panel, which is the inspection object 10, is seated at the inspection position, water is flowed through the oil film forming unit 20 to the inspection object 10 to form a water layer.

Here, when an oil film is formed on the inspection object 10 by the ultrasonic waterfall method, if there is air bubbles between the probe 31 and the inspection object 10, the ultrasonic waves do not reach the inspection object 10 and are reflected. , It is difficult to accurately inspect the inspection target 10.

Therefore, it is very important to form an oil film without bubbles on the inspection object 10.

In the present invention, when an oil film is formed on the inspection object 10, in order to prevent bubbles from occurring in the oil film, water supplied through the first water supply pipe 21 and the second water supply pipe 22 collides with each other to vortex. Prevents it from occurring.

For example, the water supplied through the first water supply pipe 21 is rapidly supplied by using the first vortex prevention jaw 21a formed in the space inside the oil film forming portion 20 to supply the second water supply pipe 22 It prevents vortices from colliding with the water supplied. Here, due to the first vortex prevention jaw 21a, water supplied through the first water supply pipe 21 is blocked from being rapidly supplied, and the supplied water is stored in the space 21b. Subsequently, when the water level of the water stored in the space 21b reaches a certain level or more, the stored water flows gently to the rear end on the first vortex prevention jaw 21a. In this way, the water supplied through the first water supply pipe 21 is prevented from being suddenly supplied. In addition, the water supplied through the second water supply pipe 22 is rapidly supplied using the second vortex prevention jaw 22a formed in the space inside the oil film forming portion 20 to supply the first water supply pipe 21. It prevents vortices from colliding with the water supplied. Here, the supply of water supplied through the second water supply pipe 22 is suddenly blocked due to the second vortex prevention jaw 22a, and the supplied water is stored in the space 22b. Subsequently, when the level of the water stored in the space 22b reaches a certain level or more, the stored water flows gently to the rear end on the second vortex prevention jaw 22a. Thus, the water supplied through the second water supply pipe 22 is prevented from being suddenly supplied.

As a result, the water supplied through the first water supply pipe 21 and the second water supply pipe 22 is prevented from colliding with each other, thereby preventing the generation of bubbles caused by the vortex during the collision. do.

As described above, in the state in which bubbles are suppressed by suppressing vortices, an oil film is formed on the inspection object 10 using the oil film forming hole 23 so that an appropriate water pressure is evenly supplied and an oil film is evenly formed.

Here, the oil film forming hole 23 is formed in plural in the lower portion of the body 24 to discharge water that has passed through the first vortex prevention jaw 21a and the second vortex prevention jaw 22a downward to be inspected 10 To form an oil film. Here, the oil film forming hole 23 is formed in plural in the same size while maintaining a predetermined interval, and is formed in a circular shape around the probe 31 to spray water on the same principle as a shower, so that a sufficient oil film is obtained even at a small flow rate. Can form.

On the other hand, the present invention is possible to form an oil film on the inspection object 10 in the same manner as described above, but as another method, the flow rate of the supplied water is sensed, and the transducer 31 and the inspection object ( 10) It is possible to use a method of optimally forming an oil film by adjusting the distance between them.

For example, the oil film forming unit 20 uses first and second flow sensors 21c and 22c to detect the amount of water supplied through the first and second water supply pipes 21 and 22, The flow rates of water supplied through the first and second water supply pipes 21 and 22 are respectively detected and transmitted to the distance adjusting means of the manual stage 50.

The distance adjustment means of the manual stage 50 moves the bubble detection unit 30 up and down to adjust the distance between the probe (transducer) 31 and the inspection object 10.

That is, the distance adjusting means controls the up and down feed of the bubble detection unit 30 according to the flow rate detected through the first and second flow rate sensors 21c and 22c built in the oil film forming unit 20 to probe ( 31) Adjust the distance between the object to be inspected (10). Here, the distance adjusting means compares the detected flow rate with a preset reference flow rate, controls the transfer of the bubble detection unit 30 so that the distance between the water guide and the transducer increases when the detected flow rate is greater than the reference flow rate, and detects the detected flow rate. When the flow rate is smaller than the reference flow rate, the transport of the bubble detection unit 30 is controlled such that the distance between the water guide and the transducer is reduced. As a method of controlling the transfer, a commonly known gear device can be used. The gear device may use a ball nut type, a rack pinion type, or the like.

5 is an explanatory diagram of the distance between the inspection object and the transducer in the present invention, A is the distance between the water guide (water guide) and the transducer (31), is the distance that is the most important for forming the oil film. B is the distance between the water guide and the object to be inspected 10 and does not affect the formation of the oil film at all. C is the total length of the oil film, and has a fixed value as the focal length of the transducer 31. The water guide means the bottom end of the body 24 of the oil film forming portion 30.

If the amount of water compared to the above A is large or does not fit, there is a problem in acquiring the image during inspection due to air in the waterpath as shown in the upper image shown in FIG. 6, and if the size of A compared to the amount of water supplied is appropriate As shown in the lower image shown in 6, an optimal image can be obtained during inspection.

Therefore, the present invention is a method of detecting a flow rate of water supplied using a flow sensor, and using the distance adjusting means of the manual stage 50 according to the detected flow rate to move the bubble detection unit 30 up and down the transducer 31 ), the distance between the transducer 31 and the water guide is adjusted to form an optimal oil film according to the flow rate.

On the other hand, in the state in which an oil film is formed on the object 10 to be inspected in the same manner as described above, the pulse corresponding to the high-frequency ultrasound is generated and transmitted to the probe 31 by the pulse/receiver 32 of the bubble detection unit 30. The transducer probe 31 transmits the transmitted high-frequency ultrasonic waves to the inspection target 10. Thereafter, the ultrasonic signal reflected from the inspection object 10 is received by the probe 31 and transmitted to the pulse/receiver 32.

Here, in the OLED panel, the FSM and the FSA or FSP are adhered to the lower FSM, and TFT & OLED are positioned on the upper part of the OLED panel. In the process of the FSM and the FSA or FSP, air bubbles are generated in the FSC material during instability. At this time, due to the difference in density of the material, ultrasonic reflection or transmission is performed in each region, and ultrasonic reflection is performed in the region where bubbles are generated. The ultrasonic wave reflected from the air bubbles is received by the probe 31 in the next step, and in the next step, the probe 31 converts the reflected ultrasonic wave into an electrical signal and transmits it to the pulse/receiver 32. In the next step, the analog-to-digital converter 33 converts the analog electrical signal transmitted through the pulse/receiver 32 into a digital signal corresponding thereto. The digital signal converted here becomes a bubble detection signal. The bubble detection signal thus converted is transmitted to the image processor 40 in the next step.

The image processor 40 collects the bubble detection signal detected by the bubble detection unit 30 in the image converter, and converts the bubble detection signal collected by the image processing algorithm into an image. Subsequently, the image converter displays the converted image signal on a screen through a display.

The inspector looks at the inspection image displayed on the screen of the display and visually checks whether air bubbles are generated.

This method may cause discomfort for the examiner to constantly look at the screen when examining the examination object.

Therefore, in order to solve the inconvenience of the manual determination method, the bubble determination unit may automatically determine the presence or absence of bubble detection by analyzing color information for each pixel of the unit image image converted by the image converter.

If a bubble is generated to the extent that a defect is caused as a result of the determination, the bubble detection alarm unit is informed.

As a result of the determination by the bubble determination unit, the bubble detection alarm unit generates an alarm for bubble detection through audio-visual if the bubble is detected information.

When such an automatic method is used, the inspector can recognize the presence or absence of air bubbles in the inspection object by conveniently recognizing that an alarm is generated while performing other tasks without the inconvenience of constantly viewing the screen.

The invention made by the present inventors has been described in detail according to the above embodiment, but the present invention is not limited to the above embodiment and can be changed in various ways without departing from the gist thereof. It is obvious to those who have it.

The present invention is applied to a technique for detecting bubbles in an OLED panel by a non-destructive inspection method.

10: Inspection target (OLED panel)
20: oil film forming part
21, 22: first and second water supply pipes
21a, 22a: first and second vortex prevention jaws
21b, 22b: space
21c, 22c: first and second flow sensors
30: bubble detection unit
31: transducer (probe)
40: image processor
50: manual stage

Claims (8)

An apparatus for controlling the formation of an oil film when detecting bubbles in a display panel by an ultrasonic waterfall type non-destructive inspection method,
An oil film forming unit that flows water to the inspection object to form an oil film;
A bubble detection unit that transmits ultrasonic waves to the inspection object on which the oil film is formed, and outputs a signal reflected by the density difference of the inspection object as a bubble detection signal; And
And an image processor for converting the bubble detection signal detected by the bubble detection unit into an image,
The oil film forming portion has a circular body having a space therein; First and second water supply pipes which are installed opposite to one end of the body and have a space formed therein to supply water; A first vortex prevention jaw to prevent water from being supplied through the first water supply pipe rapidly and colliding with water supplied through the second water supply pipe to generate vortex; A second vortex prevention jaw to prevent water bubbles caused by vortex from colliding with the water supplied through the first water supply pipe by rapidly supplying water supplied through the second water supply pipe; It is formed on the lower portion of the body and the OLED panel in the form of an ultrasonic waterfall, characterized in that it comprises an oil film forming hole for discharging water passing through the first vortex prevention jaw and the second vortex prevention jaw downward to form an oil film on the inspection object Equalization device at the time of inspection.
The method according to claim 1, The inspection object is a liquid crystal display panel or an OLED (Organic Light Emitting Diodes) panel, an ultrasonic waterfall method characterized in that the oil film equalization device for inspection of the OLED panel.
delete The method according to claim 1, The oil film forming hole is formed in a plurality, located at regular intervals of the same size to form a uniform film even at a small flow rate.
The method of claim 1, wherein the oil film forming unit further includes first and second flow sensors for detecting the amount of water supplied through the first and second water supply pipes during the inspection of the OLED panel using the ultrasonic waterfall method. Oil film equalization device.
The method according to claim 1, Manual bubble (Manual stage) for adjusting the distance between the probe (transducer) and the inspection object by moving the bubble detection unit up and down further comprising an oil film during inspection of the OLED panel Equalization device.
The method according to claim 6, The manual stage is a distance adjustment means for adjusting the distance between the probe and the inspection target by controlling the up and down conveyance of the bubble detection unit according to the flow rate detected through the first and second flow sensors built in the oil film forming unit An ultrasonic waterfall method characterized in that it comprises an oil film equalization device for inspection of the OLED panel.
In claim 7, the distance adjusting means compares the detected flow rate and the reference flow rate, and if the detected flow rate is greater than the reference flow rate, controls the transport of the bubble detection unit so that the distance between the water guide and the transducer increases, and the detected flow rate When it is smaller than the reference flow rate, an ultrasonic waterfall method, characterized in that controlling the transport of the bubble detection unit so that the distance between the water guide and the transducer is smaller, the oil film equalization device during inspection of the OLED panel.

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