KR100499065B1 - Method of testing backlight lamps of LCD Module - Google Patents

Abstract

The present invention relates to a test method of a liquid crystal display module (LCM), and more particularly to a test method of an LCD module with a backlight test function that can test the characteristics of the LCM backlight in the LCD module production process. It is about.

The apparatus of the present invention is an LCD module test system which is capable of testing an LCD module mounted on a pallet in accordance with a drive signal transmitted from a host computer, wherein the pallet is connected to a drive signal connecting portion and a drive signal for connecting an external drive signal. A test board comprising a drive control unit for applying a power supply, an inverter control unit for controlling an inverter, a test module including an LCD module and a power generation unit for generating power to be supplied to the inverter side, an inverter board for applying power to a backlight lamp of the LCD module, and a test result It consists of a status display board for displaying the status.

Therefore, according to the present invention, it is possible to test the backlight characteristics of up to six LCD modules, thereby enabling a more accurate test.

Description

Method of testing backlight lamps of LCD Module

The present invention relates to a test method of a liquid crystal display module (LCM), and more particularly to a test of an LCD module having a backlight test function that can also test the characteristics of the LCD module backlight in the LCD module production process. It is about a method.

In general, an LCD module (LCM) is a display device including a panel in which liquid crystal is injected between a substrate and a substrate, a driver for driving the panel, a backlight (B / L), and the like. Widely used in monitors, etc.

These LCD modules are manufactured on the basis of precise semiconductor technology, and require complex testing in the manufacturing process because they are complex systems containing a myriad of devices. In particular, in the LCD production line, a pallet is used to carry out various tests on the mounted LCD module while moving the produced LCD module along the production line to improve the test efficiency. In general, to test the LCD module, a power supply (Vdd1 / Vdd2, data level, B / L, etc.) for operating the LCD and driving signals (Vsync, Hsync, CLK, RGB data, etc.) for driving the pixels are required. In this case, the pallet for testing shall provide these signals.

However, the conventional pallet has a problem that a sufficient test is not made because the function of testing the backlight of the LCD module is insufficient.

The present invention has been proposed to solve the above problems, an object of the present invention is to provide a test method of the LCD module with a backlight test function that can test the backlight performance of the LCD module.

In order to achieve the above object, the apparatus of the present invention is an LCD module test system which is capable of testing an LCD module mounted on a pallet according to a driving signal transmitted from a host computer, wherein the pallet is

A drive board connecting part for connecting an external drive signal, a drive control part for applying a drive signal, an inverter control part for controlling the inverter, a test board including an LCD module and a power generation part for generating power to be supplied to the inverter side, and a backlight of the LCD module. Inverter board for applying power to the lamp, characterized in that consisting of a status display board for displaying the test result status.

In addition, in order to achieve the above object, the method of the present invention, in the test method of the LCD module that can test the LCD module mounted on the pallet in accordance with the drive signal transmitted from the host computer, when the pallet arrives pallet ID Reading; Receiving model information from a host computer and downloading the test data to a pallet if it matches the actual model, and storing the test data in YPIROM; Setting power sources VBL and VBR; Testing a lamp (CCFL); Storing and transmitting the test results; And setting a dog pin according to the test result.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

First, the LCD module uses a Cold Cathode Fluorescent Lamp (CCFL) as a light source of the backlight. Conventional fluorescent lamps are called Hot Cathode Fluorescent Lamps (HCFLs) by heating cathodes with filaments to generate hot electrons and discharging them. Such HCFLs have difficulty in miniaturizing electrode structures. CCFL is a simple structure with no filament and is widely used in LCD backlights. CCFL requires an inverter because a high voltage is applied to the anode to discharge electrons. That is, an inverter used as a backlight power source of the LCD module receives a DC voltage and outputs an AC voltage having a constant frequency.

FIG. 1 is a diagram illustrating a concept of testing an LCD module while moving a zone using a pallet according to the present invention. Referring to FIG. 1, the LCD production / test line is equipped with a test target LCD module, a pallet 110 for providing a driving signal and power required for the LCD module, and a transport belt 120 for transferring the pallet 110. , Consists of four test baths (a ~ d) for testing the LCD module loaded on the pallet (110). And each test is equipped with a computer system (102a, 102b, 102d) equipped with a test program, when the pallet 110 equipped with the LCD module to be tested arrives automatically connected to the set value and test for the LCD module Perform the LCD module test in this manner. At this time, each computer can be connected to the main computer via LAN.

For example, the first test control (a) is an in-line test control that mounts an LCD module on a pallet and sets a test pattern or a method required for the LCD module under test. These settings can be set on the computer in advance and downloaded from the main computer or PC and set automatically according to the type of LCD module on the pallet. When the test is finished in the first test control (a), the pallet 110 is moved to the second test control (b) by the transfer belt 120 and tested. If the second test cloud (b) is a test cloud using an external pattern, the LCD module mounted on the pallet 110 is tested according to a test pattern provided from the outside. After the test in the second tide, the pallet 110 is moved to the third test tide (c) by the transfer belt 120. If the third test bath (c) is a burn-in chamber (environmental test bath), the LCD module is tested for a predetermined time in a predetermined temperature and humidity environment. When the test is completed in the third transport, the pallet 110 is moved to the fourth test transport (d) again, and the final test is made. The amount / addition is determined according to the test result, and the test for the corresponding LCD module is completed.

As described above, the pallet 110 tests the LCD module by moving each zonal force by the transport belt 120 in the test line after mounting the LCD module as a test object.

Figure 2 is an example of the overall configuration of the test apparatus according to the present invention, the test apparatus of the present invention is connected to the PLC 202, the test PC 210, the barcode reader 204, ID card read / write to instruct the test 206, a matching unit 208, and a pallet 220, and the pallet 220 is provided with an LCD test board 230, an inverter board 240, and a status display board 250. The LCD test board 230 includes an external LCM drive signal connection unit 231, a drive control unit 232, a VBL power generation unit 233, and an inverter control unit 234, and the inverter board 240 includes six inverters ( 242-1 to 242-6). Here, VBL is an inverter input power of about 12 to 18V, and VBR is an inverter brightness power source that can vary in units of 0.1V from 0 to 3V.

Referring to Figure 2, PLC 202 is a host system for controlling the overall LCD module production process, the test PC 210 is equipped with a TAB program and LIS program to perform the test according to the present invention to control the test . The test PC 210 and the pallet 220 are contacted with each other through the matching unit 208 to supply a signal for testing, and are separated again when the test is completed.

Computer (210) is equipped with a test program (TAB & LIS) according to the present invention model information of the LCD module mounted on the pallet 220 through a barcode reader 204 and ID card lead / light 206, etc. The LCD driving information is read and transmitted to the pallet 220. The main console screen provided by the test program running on the computer 210 is as shown in FIGS. 6 to 10.

The test board 230 mounted on the pallet drives the LCM module according to the driving signal transmitted from the test PC 210 to perform a pattern test. In particular, the test board 230 according to the present invention performs a defect detection function for the backlight (CCFL) of the LCM, and provides a constant isocurrent for each CCFL.

The inverter board 240 supplies power to the backlight of the LCM to test the characteristics of the backlight, and the test results are displayed on the status display board 250. That is, the LCD test board 230 downloads the test information about the LCD module from the PC 210, stores it in the internal EPIROM, generates a driving signal, and provides the LCD module through the buffer board. The value of monitoring the Vdd and B / L voltage / current values applied to the module is compared with the set limit, and when the value is out of the limit, the status information is transmitted to the status display board 250 to display it. The inverter board 240 includes six inverters to generate and provide power for backlights of one to six LCD modules. The buffer board (not shown) receives the driving signal from the LCD test board 230 and converts the TTL driving signal, the LVDS driving signal, and the TMDS driving signal required by the LCD type to the LCD module. In addition, the status display board 250 turns on / off the corresponding lamp according to the control signal received from the LCD test board 230.

3 is a flowchart illustrating a test procedure according to the present invention, FIG. 4 is a detailed diagram of a backlight test configuration according to the present invention, and FIG. 5 is a flowchart illustrating a backlight test procedure according to the present invention.

Referring to FIG. 3, when the pallet arrives, the TAB program of the test PC 210 reads the pallet ID through the barcode reader and reads the PID through the card reader (S1 to S3). Then, the model information is downloaded from the host computer (management PC) and transferred to the LIS program (S4, S5).

The LIS program receives model information and compares it with the actual model, and if it matches, downloads data to the pallet firmware (F / W) (S6 to S8).

The pallet's firmware recognizes the test rhythm when the power is on and receives data from the LIS program when the flicker / final test rhyme (S31, S32). Then, the checksum (CS) value is checked to determine whether there is a transmission error, and if it is normal, it is stored in the Y pyrom of the pallet (S9 and S10). Then set VBL and VBR and test CCFL (S12, S13).

4, the high and low terminals of the inverters 242-1 to 242-6 are connected to each of the CCFLs CCLF1 to CCFL6. That is, inverter 1 242-1 supplies power to CCFL1, inverter 2 242-2 supplies power to CCFL2, and inverter 6 242-6 supplies power to CCFL6 in the same manner. .

In the test configuration, as shown in FIG. 5, the procedure of testing the CCFL is to turn on the inverter 1 and the inverter 6 and then check the CCFL 1 and the CCFL 6 (501, 502). After the CCFL2 and CCFL5 is checked (503, 504). In the same way, after turning on Inverter 3 and Inverter 4, check CCFL3 and CCFL4 (505,506) and if it is normal, if CCFL is normal, if any abnormality is detected in CCFL, LCM fault is displayed and then dog pin Denotes "01" (507,508).

After testing the CCFL as described above, the state is output, the result is stored, and the result is transmitted to the LIS program (S14, S15). The LIS program determines the processing result and if it is normal, it writes ST = 2 and IN = 0 in LIPA. If abnormal, ST = 2, IN = X and transmits the result to the TAB program (S16 ~ S19).

The TAB program checks the LIPA file (LIPA.ini) and sends the PID to the host computer (management PC), and receives the backlight file information file (bllamp information.txt) from the host computer. Is set to "11", if there is an error in the pallet, the dog pin is set to "10" and if there is an error in the LCM module, the dog pin is set to "01" and the PLC is operated to end the test. At this time, the test result is stored in the backlight test file (blchk.txt) (S20 ~ S24). In FIG. 3, step S33 indicates a retry, and if the state is an error even after two or more retries, the error is displayed by setting the dog pin to "10" (S34). S35 represents model information, S36 and S38 represent a backlight inspection file (blchk.txt), and S37 represents a backlight lamp information file (bllamp information.txt).

6 is a main screen of the LIS program according to the present invention. The main screen is divided into a status console screen on the left and a control console screen on the right, and corresponds to the "information control" of the control console screen to set desired information. Click in the box to enter it. That is, in order for the test program to provide data related to the setting to the pallet, the corresponding LCD module must be registered in advance. In the case of a new model, the new LCD module must be registered in the test program before input.

To register a new model, click the relevant box (any one of System Information, LCM Information, Pattern Information, or Manual Test Mode) in "Information Control". A window for requesting a password will appear. At this time, the 'LCM information' box is used to newly register the LCD or to add, change, or delete the information of the registered LCD, that is, the LCD resolution, driving timing, driving voltage, driving pattern file, and limit information. The 'information' box is used to create a pattern or to add, change or delete information about the driving pattern for driving in an internal test or aging chamber. The 'System Information' box is used to change the information on whether or not to perform an internal test.

Clicking on the 'System Information' box of the information control opens the system information screen as shown in FIG. Referring to FIG. 7, a box of 'ZONE selection' is used to distinguish whether the system is an AGING or FINAL, and a 'production line setting' box selects a line ID. There are LCD mode control, port selection, and pre-aging control. Afterimage pattern setting and FPGA download information can be displayed and inputted.

When the 'LCM information' box is clicked, the LCM information screen as shown in FIG. 8 appears. When registering a new LCD module, set the model name in "New Model Information", and set the on / off and shutdown on / off of the inverter to be used in "Inverter Setting Information". The upper and lower limits of the VBL are set in "Voltage Limit Information" and the upper and lower limits of the IBL are set in "Current Limit Information". Set VBL and VBR in "VBL Setting" and "VBR Setting" and click the "Register" button to register. Here, the CCL test time can be set on the LCM information screen, and the CCFL type can be set.

Next, the operation of the present invention configured as described above will be described with reference to FIG.

Referring to FIG. 3, when the pallet arrives at the test bath, contact is automatically made. At this time, information data, an input voltage, and an external tester pattern signal for driving the LCD module are input through the automatic connection connector.

Subsequently, if the automatic contact is determined to be successful or not, the time is checked and if the time exceeds the predetermined time, the automatic connection failure error occurs and then terminates.

If Auto-Contact is successful, turn on and reset the power, and then receive various information such as LCD type, operating power, data signal level, display pattern, display time, current voltage value from the test program of the computer, Store in this pyrom. Based on the information from the computer, the pallet assembly determines the LCD drive clock, panel operating power, and data signal level.

When the setting is completed as described above, select whether it is a test by an external pattern or a test by an internal pattern, turn on the LCD driving power, and drive the LCD with an internal pattern or an external pattern signal to drive the LCD according to the selection. That is, the pallet assembly outputs the VCC, VDD, B / L power supply, LCD driving signal and data signal according to the setting information transmitted from the computer. At this time, VCC and VDD are input to the LCD module, and BL power is supplied through the inverter to turn on the backlight of the LCD module. The external tester pattern signal, that is, the external drive signal and the data signal are input to the pallet assembly through the PC side connector and transmitted to the LCD module through the buffer board.

In this way, the LCD module is driven according to the set driving pattern to monitor the voltage / current values of power applied to the LCD module while displaying the pattern. The sensed voltage / current value is read by the CPU through the A / D converter and sent back to the computer. If the current sensing value is larger or smaller than the set limit, it indicates overcurrent or no lighting. In addition, it checks the VDD and the output signal and transmits the error to the PC.

As described above, according to the present invention, after setting various parameters required for the test target LCD module in the line for producing and testing the LCD module, the test set is automatically downloaded according to the test target LCD module. By shortening the test time of the LCD module, the test can be efficiently performed. In particular, according to the present invention, it is possible to test the backlight characteristics of up to six LCD modules, thereby enabling a more accurate test.

In addition, in the past, even when a bad CCFL is included among several CCFLs, it was difficult to determine whether a product was released or which CCFL was bad. However, applying the principles of the present invention, it is also the cause of the bad CCFL among the CCFL mounted on the LCM (CCFL high voltage, high open, low open, high short, low short, leakage, high-low back inverse) Etc.). Therefore, accurate product testing of LCM is performed to block the defect of the product to improve the reliability. In addition, if the CCFL is bad, the LCM NG (Not Good) LED can be turned on in the status board to stop the LCM test in advance, thus eliminating the time for checking the bad LCM.

1 is a schematic diagram of an LCD module test system to which the present invention is applied;

2 is a block diagram showing the configuration of a test system according to the present invention;

3 is a flow chart showing a test procedure according to the present invention,

4 is a detailed view of a backlight test configuration according to the present invention;

5 is a flow chart illustrating a backlight test procedure in accordance with the present invention;

6 is a main screen of the test according to the present invention,

7 is a system information screen according to the present invention;

8 is an LCM information screen according to the present invention.

☞ Explanation of symbols for main parts of drawing

202: PLC 204: barcode reader

206: ID card reader 208: matching unit

210: test computer 220: pallet

230: LCD test board 231: external LCM drive signal connection

232: drive control unit 233: VBL power generation unit

234: inverter control unit 240: inverter board

242-1 ~ 242-6: Inverter 250: Status display board

Claims (7)

delete delete A drive board for connecting an external drive signal, a drive control unit for applying a drive signal, an inverter control unit for controlling the inverter, a test board including an LCD module and a power generation unit for generating power to be supplied to the inverter side, and a backlight of the LCD module. In the test method of the LCD module, it is possible to test the LCD module mounted on the pallet consisting of an inverter board for applying power to the lamp and a status display board for displaying the test result status according to the driving signal transmitted from the host computer. In Reading a pallet ID when the pallet arrives; Receiving the model information from the host computer and matching the actual model, downloading the test data to the pallet and storing the data in YPIROM; Setting a power source (VBL and VBR); A fourth step of testing a lamp (CCFL); A fifth step of storing and transmitting a test result; And The sixth step of setting the dog pins according to the test results, The fourth step of testing the lamp (CCFL) is to turn on the lamp, check whether the lamp is defective or not, and if the lamp (CCFL) is bad, the state of the defective (NG) of the LCD module Mark on board to reduce test time, The sixth step of setting the dog pin according to the test result Checking whether the error is transmitted by the checksum value during transmission, and setting the dog pin to 11 if the test result is normal, the dog pin to 10 if the pallet is abnormal, and setting the dog pin to 01 if the LCD module is abnormal. Backlight test method of the LCD module. delete delete delete delete