KR20240164055A - Faulty pixel detecting method and faulty pixel detecting system for led electric sign board - Google Patents

Abstract

The present invention relates to a method for detecting defective pixels in an LED display board and a device for detecting defective pixels. LED display board according to the present invention
The method for detecting bad pixels is (a) lighting the pixels constituting the LED display board in horizontal line units, and each horizontal line
A step of measuring the horizontal line luminance value for a line; (b) the pixels constituting the LED display board as vertical line units.
A step of lighting and measuring the vertical line luminance value for each vertical line; (c) the measured horizontal line luminance values
and a step of determining whether the measured vertical line luminance values are outside the preset reference luminance range; (d)
Horizontal and vertical lines corresponding to horizontal line luminance values and vertical line luminance values that are outside the reference luminance range are crossed.
It is characterized by including a step of judging a pixel at a position of a difference as a bad pixel. Accordingly, the reference luminance range
Detect horizontal and vertical lines that deviate from each other, and mark pixels at the locations where the detected horizontal and vertical lines intersect as defective.
By judging by pixels, defective pixels that occur among the LEDs that make up each pixel of the LED display board are detected on a pixel-by-pixel basis.
It becomes possible.

Description

FAULTY PIXEL DETECTING METHOD AND FAULTY PIXEL DETECTING SYSTEM FOR LED ELECTRIC SIGN BOARD

The present invention relates to a method for detecting defective pixels in an LED display board and a device for detecting defective pixels. More specifically, <1>

Method for detecting defective pixels in an LED display board capable of detecting defective pixels on a pixel-by-pixel basis on the entire screen of the display board and defective pixels

It's about the detection device.

<2> LED (Light Emitting Diode) refers to a light-emitting diode, a semiconductor device that emits light, and is available in red, green, blue, and yellow.

It is widely used in various electronic products and electronic display panels such as instrument panels in various colors.

<3> Among these, the LED display board arranges multiple LEDs in a matrix form, and multiple LEDs arranged in a matrix form display images.

By forming pixels for display, it is possible to display images. These LED display boards are used for advertising and various types of information.

It is installed and used in various forms on the outside or inside of buildings for transmission.

<4> Typically, the entire screen of an LED display board is composed of N×M pixels, as shown in Figure 1, with each pixel

It consists of red LED, green LED and blue LED, and implements full color depending on whether it is lit and the light intensity of each LED.

That is, the LEDs that constitute each pixel are selectively turned on according to the image data received from an image source such as a computer.

By lighting it, various information such as letters, pictures, and videos are displayed.

<5> There may be a problem in the manufacturing process of the LED display board, a defect in the LED itself that occurs during use, or a problem in supplying power to each LED.

Defective pixels may occur due to short circuits or disconnection of wires connected to the LED display. Such defective pixels may occur due to short circuits or disconnection of wires connected to the LED display.

This will act as a factor that reduces the image quality. These defective pixels are replaced during the manufacturing process or use of the LED display board.

In order to do this, a process of detecting defective pixels among all pixels that make up the entire screen of the LED display board must be performed first.

Do it.

<6> Korean Patent No. 0815587 is a failure detection device for a light-emitting diode dot matrix module capable of detecting defective pixels.

The fault detection device disclosed in the Korean registered patent is a main control device that outputs data and control signals.

It has a wealth, normal mode and detection mode and receives data and control signals from the main control unit to operate in normal or detection mode.

Open/close at least one light emitting diode of the light emitting diode dot matrix module to output display information in the light mode.

When a short circuit occurs, it includes a detection unit that outputs detection information corresponding to each open/short circuit to the main control unit.

By detecting the open/short and normal states of the LEDs in response to various operation modes, the current light emission level is

It allows you to check the operating status of the iodine and light-emitting diode dot matrix modules.

<7> However, in the case of the fault detection device disclosed in the above Korean registered patent, a separate circuit is used to detect a fault in the LED display board.

There is a disadvantage in that it increases manufacturing costs because the configuration is added, and errors such as failures occur in the fault detection device itself.

In this case, there is a disadvantage in that detection of bad pixels itself becomes impossible.

<8> In addition, in the manufacturing process of LED display boards, LED modules are manufactured in units of n×m, for example, 16×16, and then multiple LED modules are manufactured.

The entire screen of the LED display is configured by arranging the LED modules in matrix form again, and each LED module is used to detect defective pixels.

Measure the brightness above, and if the measured brightness is outside a certain range, it is judged as a defective LED module.

We are using a method to find defective pixels that have occurred inside the LED module.

<9> Here, although it is more accurate to measure brightness per pixel to detect bad pixels, it is more accurate to measure brightness per LED module.

Measuring brightness on a pixel-by-pixel basis is technically difficult and requires a lot of cost and time.

This point was taken into consideration.

<10> The present invention has been devised to solve the above problems, and does not add a separate circuit configuration to the LED display board.

Provided is a method for detecting defective pixels of an LED display board and a device for detecting defective pixels, which can detect defective pixels without

That's the purpose.

<11> The above purpose is, according to the present invention, in a method for detecting defective pixels of an LED display board, (a) a pixel constituting the LED display board

A step of lighting the LED display board in units of horizontal lines and measuring the horizontal line luminance value for each horizontal line; (b) lighting the pixels constituting the LED display board in units of vertical lines and measuring the vertical line luminance value for each vertical line.

Step of determining; and (c) the measured horizontal line luminance values and the measured vertical line luminance values are set as a preset reference luminance.

(d) a step of determining whether the horizontal line luminance value and the vertical line luminance value are out of the reference luminance range;

Includes a step of judging a pixel at a position where a horizontal line and a vertical line corresponding to a line luminance value intersect as a bad pixel.

This is achieved by a method for detecting defective pixels in an LED display board, characterized by:

Here, in the step (a) and the step (b), the horizontal line luminance value and the <12> vertical line luminance value are

Measured based on the luminance value of image data acquired by shooting with the camera in a state where the vertical line units above are lit.

It is characterized by being.

<13> Meanwhile, the above purpose is achieved by a device for detecting defective pixels of an LED display board according to another embodiment of the present invention.

A luminance measuring unit for capturing the screen of the light plate; a data storage unit for storing information on the reference luminance range; and the above

Controls the pixels constituting the LED display board to blink in horizontal line units and vertical line units, and the LED display board

The brightness measuring unit is turned on in the horizontal line unit and the vertical line unit, respectively, of the LED display board.

Controlling the screen to capture images, and capturing the images by horizontal line unit and horizontal line unit from the luminance measuring unit

Based on the image data, the horizontal line luminance value for each horizontal line and the vertical line luminance value for each vertical line

Detecting the degree value and whether the horizontal line luminance value and the vertical line luminance value are outside the preset reference luminance range

It determines whether the horizontal line luminance value and the vertical line luminance value corresponding to the horizontal line luminance value that are outside the above reference luminance range are

It is characterized by including a bad pixel detection control unit that determines a pixel at a position where a human and vertical lines intersect as a bad pixel.

This is also achieved by a defective pixel detection device of an LED display board.

<14> Here, information on the reference luminance range and the horizontal line luminance value and vertical line luminance value that are outside the reference luminance range

A data storage unit in which bad line information for horizontal and vertical lines corresponding to the luminance value is stored, and an image is displayed

It further includes a display unit; and the bad pixel detection control unit detects the bad line information and the bad pixel.

A log file for one piece of information can be generated and displayed via the display section.

<15> According to the present invention, the reference brightness range is set without adding a separate circuit configuration within the LED display board by the above configuration.

Detect horizontal and vertical lines that are removed, and mark pixels at the locations where the detected horizontal and vertical lines intersect as defective.

By detecting by judging by pixels, it is possible to easily replace defective pixels during the manufacturing process or use of LED display boards.

all.

<45> Figure 1 is a drawing showing the configuration of a defective pixel detection device of an LED display board according to the present invention.
<46> Fig. 2 is a control block diagram of the bad pixel detection device of Fig. 1.
<47> Figure 3 is a drawing showing the pixel configuration of an LED display board according to the present invention.
<48> Figures 4 and 5 are control flow charts for explaining a method for detecting defective pixels in an LED display board.
<49><Explanation of main numbers in the drawing>
10: LED display board 30 <50>: Bad pixel detection device
<51> 31: Luminance measurement unit 32: Bad pixel detection control unit
<52> 33: Data storage unit 34: Display unit

<16> Hereinafter, the present invention will be described in detail with reference to the attached drawings.

<17> The defective pixel detection device (30) of the LED display board (10) according to the present invention comprises a luminance measuring unit, as shown in FIGS. 1 and 2.

(31), a display unit (34), a data storage unit (33), and a bad pixel detection control unit (32). Here, the display

The laser beam (34), data storage unit (33) and bad pixel detection control unit (32) are, as shown in Fig. 1, computer-like

It can be provided in the form of a processing device.

<18> The brightness measurement unit (31) captures the screen of the LED display board (10) and measures the brightness of the image displayed on the screen. Here, the brightness

The measurement unit (31) is provided in the form of a CCD camera or a CMOS camera and captures an image obtained by capturing the screen of the LED display board (10).

The information is transmitted to the bad pixel detection device (30).

<19> The data storage unit (33) contains the reference luminance range (RBL to RBH, see Figs. 4 and 5) that serves as a criterion for detecting defective pixels.

Information is stored. The display unit (34) displays an image on the screen under the control of the bad pixel detection control unit (32).

By displaying the log file generated by the control unit (32) on the screen, information on defective pixels is displayed.

Display visually.

<20> The bad pixel detection control unit (32) detects the pixels constituting the LED display board (10) by blinking in horizontal line units and vertical line units.

And, the bad pixel detection control unit (32) controls the LED display board (10) to detect horizontal lines and vertical lines.

In each lit state, the brightness measuring unit (31) is controlled to capture the screen of the LED display board (10).

<21> Referring to Fig. 3, a defective pixel detection control unit (32) detects n horizontal pixels constituting an LED display board (10).

The LED display board (10) is controlled so that the lines are sequentially lit, for example, from the top to the bottom. Here, the bad pixel detection control unit (32) controls the LED display board (10) by applying a video signal to light only a specific horizontal line.

The light plate (10) can be controlled to light up in horizontal line units.

In this process, the bad pixel detection control unit (32) detects the LED brightness when one horizontal line is lit.

Controlling the screen of the scoreboard (10) to capture image data for each horizontal line (hereinafter referred to as 'horizontal image data')

is transmitted from the luminance measuring unit (31).

<23> In the same way, the bad pixel detection control unit (32) detects m vertical lines that constitute the LED display board (10), for example, on the left.

The LED display board (10) is controlled to light sequentially from the west to the right. Then, the defective pixel detection control unit (32) is

Control the luminance measuring unit (31) to capture the screen of the LED display board (10) while my vertical line is lit, so that each vertical

Image data for the line (hereinafter referred to as “vertical image data”) is received from the luminance measurement unit (31).

<24> Through the above method, horizontal image data and vertical image data for each horizontal line and vertical line of the LED display board (10)

When data is acquired, the bad pixel detection control unit (32) detects each image based on the horizontal image data and the vertical image data.

Detect luminance values for horizontal and vertical lines. Here, the luminance values detected based on horizontal image data are

The luminance value detected based on the vertical image data is called the vertical line luminance value (VB, see Fig. 4).

It is defined and explained as (see Fig. 5).

<25> Meanwhile, the bad pixel detection control unit (32) detects the horizontal line for each horizontal line and vertical line of the LED display board (10) as described above.

When the human luminance value (HB) and vertical line luminance value (VB) are detected, the horizontal line luminance value (HB) and vertical line luminance value (VB) are data.

It determines whether the reference luminance range (RBL ~ RBH) stored in the storage unit (33) is out of range, and the reference luminance range (RBL ~ RBH) is

Defective lines for horizontal and vertical lines corresponding to horizontal line luminance value (HB) and vertical line luminance value (VB) that deviate from the horizontal line luminance value

Generates information. Here, the bad pixel detection control unit (32) can store the bad line information in the data storage unit (33).

all.

<26> And, the bad pixel detection control unit (32) detects horizontal line luminance values (HB) and vertical line luminance values that are outside the standard luminance range (RBL ~ RBH).

Pixels at the intersection of horizontal and vertical lines corresponding to the luminance value (VB) are judged as defective pixels.

<27> For example, referring to Fig. 3, the horizontal line luminance value (HB) for the third horizontal line among the horizontal lines is the reference luminance.

The vertical line luminance value (VB) for the second vertical line is out of the reference luminance range (RBL ~ RBH).

If it is judged to be out of (RBL ~ RBH), the pixel where the 3rd horizontal line and the 2nd vertical line intersect, i.e. m×n

The third pixel from the top and the second pixel from the left are detected as defective pixels.

<28> Here, the bad pixel detection control unit (32) generates a log file for bad line information and bad pixel information.

It can be stored in the data storage unit (33), and the generated log file can be displayed through the display unit (34) as described above.

You can do it.

<29> Through the above configuration, without adding a separate circuit configuration within the LED display board (10), the standard brightness range (RBL ~ RBH)

Detect horizontal and vertical lines that are out of range, and fire the pixels at the positions where the detected horizontal and vertical lines intersect.

By detecting by judging by the quantity of pixels, defective pixels can be easily replaced during the manufacturing process or use of the LED display board (10).

It happens.

<30> In the above-described embodiment, the bad pixel detection control unit (32) detects the horizontal line luminance value (HB) for the entire horizontal line and vertical line.

It was explained that the vertical line luminance value (VB) is detected and then compared with the reference luminance range (RBL ~ RBH), but one horizontal

Detection and reference luminance range of horizontal line luminance value (HB) (or vertical line luminance value (VB)) for a line (or vertical line)

After detection of a bad line through comparison with (RBL ~ RBH) is completed, detection for the next horizontal line (or vertical line)

And of course, the comparison can proceed. Also, the order of detection and comparison of horizontal and vertical lines can be changed.

Of course.

<31> Hereinafter, a method for detecting defective pixels of an LED display board (10) according to the present invention will be described in detail with reference to FIGS. 4 and 5.

Here, the LED display board (10) is composed of m×n pixels, i.e., n horizontal lines and m vertical lines.

Let me explain using an example of what it consists of.

<32> First, the horizontal line luminance value (HB) for the first horizontal line is measured when the first horizontal line is lit (S40).

(S41). Here, the method of measuring the horizontal line luminance value (HB) is as described above, so a detailed description thereof is omitted.

Then, it is determined whether the measured horizontal line luminance value (HB) is within the preset reference luminance range (RBL ~ RBH) <33>.

And (S42), if it is determined that the horizontal line luminance value (HB) is within the reference luminance range (RBL ~ RBH), the first horizontal

Turn off the line (S44).

<34> On the other hand, if the horizontal line luminance value (HB) at step S42 is judged to be outside the reference luminance range (RBL ~ RBH),

When the horizontal line is judged to be a bad line (S43), the corresponding information is stored in the data storage unit (33) and then the first horizontal line is

Turn off the light (S44).

<35> And, the measurement of the horizontal line luminance value (HB) and the judgment of whether it is included within the reference luminance range (RBL ~ RBH) are performed for all horizontal lines.

Determine whether the horizontal line has been terminated (S45), and if not terminated for all horizontal lines, proceed to the next horizontal line.

After lighting the human body (S46), steps S41 to S45 are performed to detect defective lines among the entire horizontal lines.

<36> Meanwhile, when the detection of defective lines for all horizontal lines is completed through the above process (S45), the detection of defective lines for vertical lines is completed.

Detection of bad lines proceeds as shown in Fig. 5.

<37> First, the vertical line luminance value (VB) for the first vertical line is measured when the first vertical line is lit (S50).

(S51). Here, the method of measuring the vertical line luminance value (VB) is as described above, so a detailed description thereof is omitted.

<38> Then, it is determined whether the measured vertical line luminance value (VB) is within the preset reference luminance range (RBL ~ RBH).

And (S52), if it is determined that the vertical line luminance value (VB) is within the reference luminance range (RBL ~ RBH), the first vertical

Turn off the line (S54).

<39> On the other hand, if the vertical line luminance value (VB) at step S52 is judged to be outside the reference luminance range (RBL ~ RBH),

When the vertical line is judged to be a bad line (S53), the corresponding information is stored in the data storage unit (33) and then the first vertical line is

Turn off the light (S44).

<40> And, the measurement of the vertical line luminance value (VB) and the judgment of whether it is included within the reference luminance range (RBL ~ RBH) are performed for all vertical lines.

Determine whether the vertical line has been terminated (S55), and if not terminated for all vertical lines, proceed to the next vertical line.

After lighting the human body (S56), steps S51 to S55 are performed to detect defective lines among the entire vertical lines.

<41> When the detection of defective lines for all horizontal and vertical lines is completed (S55), the vertical lines judged as defective lines are

By judging the pixel where the line and the horizontal line intersect (S57), the pixel is detected as a defective pixel, and the correction for the defective pixel is made.

The view is displayed on the display unit (34) (S58).

<42> In the above-described embodiment, the reference luminance range (RBL to RBH) for horizontal lines and vertical lines is explained as an example.

However, it is of course possible that the value may be different.

<43> In addition, in the above-described bad pixel detection method, bad pixels of vertical lines are detected after detecting bad lines of horizontal lines.

Although this is an example, the order can be changed, and for horizontal lines (or vertical lines, the same applies hereinafter).

After the horizontal line luminance value (HB) for the entire horizontal line is measured, comparison with the reference luminance range (RBL ~ RBH) may be performed.

there is.

<44> Although some embodiments of the present invention have been illustrated and described, those skilled in the art will appreciate that

It will be appreciated that those skilled in the art may modify the present embodiments without departing from the principles or spirit of the invention.

The scope of the alias will be determined by the appended claims and their equivalents.

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Claims (4)

In a method for detecting defective pixels in an LED display board,
(a) The pixels constituting the LED display board are illuminated in horizontal line units, and the horizontal line brightness for each horizontal line is
Step of measuring the degree value;
(b) The pixels constituting the LED display board are illuminated in vertical line units, and the vertical line brightness for each vertical line is
Step of measuring the degree value;
(c) The measured horizontal line luminance values and the measured vertical line luminance values are outside the preset reference luminance range.
A step for determining whether or not;
(d) Horizontal line and vertical line corresponding to horizontal line luminance values and vertical line luminance values that are outside the above reference luminance range.
A defective LED display board characterized by including a step of determining a pixel at a position where a person intersects as a defective pixel.
How to detect cows. In the first paragraph,
In the above steps (a) and (b), the horizontal line luminance value and the vertical line luminance value are
It is measured based on the luminance value of image data acquired by shooting with a camera while the unit is lit in vertical lines.
A method for detecting defective pixels in an LED display board characterized by: In a defective pixel detection device of an LED display board,
A luminance measuring unit for capturing the screen of the above LED display board;
A data storage unit in which information about a reference luminance range is stored;
The pixels constituting the LED display board are controlled to blink in horizontal line units and vertical line units, and the LED display board is controlled to blink in horizontal line units and vertical line units.
The luminance measuring unit is turned on when the light plate is turned on in each of the horizontal line units and the vertical line units.
Controlling the screen of the light plate to capture an image, and measuring the brightness from the luminance measuring unit in units of horizontal lines and units of horizontal lines.
Based on the captured image data, the horizontal line luminance value for each horizontal line and the vertical line for each vertical line
Detecting the line luminance value, and determining whether the horizontal line luminance value and the vertical line luminance value are outside the preset reference luminance range
It determines whether or not to do so, and corresponds to horizontal line luminance values and vertical line luminance values that are outside the above-mentioned reference luminance range.
Including a bad pixel detection control unit that determines a pixel at a position where a horizontal line and a vertical line intersect as a bad pixel
A defective pixel detection device for an LED display board characterized by: In the third paragraph,
Information on the above reference luminance range and horizontal line luminance values and vertical line luminance values that fall outside the above reference luminance range.
A data storage unit in which bad line information for corresponding horizontal and vertical lines is stored,
Further comprising a display portion on which an image is displayed;
The above bad pixel detection control unit generates a log file for the bad line information and the information on the bad pixel.
A defective pixel detection device for an LED display board characterized by displaying the above through the display unit.