CN201489225U

CN201489225U - TFT LCD programmable comprehensive performance electrical detector

Info

Publication number: CN201489225U
Application number: CN2009200520797U
Authority: CN
Inventors: 唐惠玲; 刘汉瑞; 刘志军
Original assignee: Guangdong University of Technology
Current assignee: Guangdong University of Technology
Priority date: 2009-03-04
Filing date: 2009-03-04
Publication date: 2010-05-26
Anticipated expiration: 2019-03-04

Abstract

The utility model discloses a TFT LCD programmable comprehensive performance electrical detector, which comprises a control module (1), a D/A conversion module (2), an optoelectronic coupling switch module (3), a power supply module (4) and a keyboard (5), wherein the control module (1) is connected with the D/A conversion module (2), the optoelectronic coupling switch module (3) and the keyboard (5) respectively; the power supply module (4) supplies power to the control module (1), the D/A conversion module (2), the optoelectronic coupling switch module (3), the power supply module (4) and the keyboard (5). The output of the electrical detector of the utility model can drive TFT LCD to generate seven variable voltage signals including GG, ODD, EVEN, DATA (R), G, B and the like, generate ten pictures in black, a first gray level, a second gray level, a third gray level, white, red, green, blue and other colors, and the electrical detector can detect defects of the TFT LCD such as black screen, bright spots and bright lines and can detect the defects of TFT LCDs of different sizes from different manufacturers by simply changing software under the condition of unchanged hardware circuit. And the electrical detector has the advantages of improving the rate of finished LCM, reducing cost of enterprises, along with low cost, high display defect rate and high detection speed.

Description

A kind of TFT LCD programmable combination property electric logging device

Technical field

The utility model is a kind of TFT LCD programmable combination property electric logging device, belongs to the renovation technique of TFT LCD programmable combination property electric logging device.

Background technology

At present, existing TFT LCD can not reach 100% yield rate in process of production, there is defective more or less, do not work, exist defectives such as bright spot or bright line such as the LCD point, therefore, LCD being sticked before IC makes the LCM module, need add electric drive signal to LCD and detect, reduce the waste of IC and reduce cost.

TFT LCD screen mainly is made of materials such as backlight, glass substrate, circuit layer, liquid crystal layer, filter and alignment films.And most probable produce defective just at circuit layer, i.e. tft array layer.TFT practical function such as same switch, liquid crystal such as same electric capacity, in the time of switch closure, signal writes liquid crystal capacitance C _LC, signal remains on the liquid crystal in the time of disconnection.The effect of memory capacitance Cs is exactly to allow charging voltage remain to frame update next time.Fig. 1 is the TFT equivalent circuit diagram of single pixel unit.TFT grids all on sweep trace (Scan line) and this row link to each other, and whether decision TFT gating, and source signal line (Data line) links to each other with this source electrode that is listed as all TFT, to liquid crystal capacitance C _LCCharge.As the voltage V that is added in the G utmost point and the S utmost point _GSGreater than threshold voltage V _ThThe time, source electrode and drain electrode conducting, the liquid crystal capacitance charging reaches display effect; Work as V _GSLess than threshold voltage V _ThThe time, the TFT switch disconnects, and liquid crystal capacitance keeps charging voltage to next scan period.

Because it is constant that liquid crystal molecule can not be fixed under certain voltage for a long time, not so can destroy the revolving property of liquid crystal molecule.But, in the time of the same GTG of display requirement, display voltage can be divided into the positive-negative polarity of same pressure differential with respect to Vcom, like this no matter be that to be added in voltage on the liquid crystal be just or negative, though the sense of rotation difference of liquid crystal molecule, the GTG that shows is the same.When requiring to show same GTG,, reach display requirement like this, also can avoid destruction liquid crystal molecule by replacing of generating positive and negative voltage.At present, for fear of scintillation and minimizing power consumption, most of TFT-LCD adopt the fixedly type of drive of Vcom voltage of some upset, the second order drive principle synoptic diagram that Fig. 2 adopts for TFT-LCD.

According to structure and the drive principle of TFT,, just can reach the effect of demonstration as long as the grid of timesharing ground each row of gating makes source signal be charged to correct display voltage to show electrode.But because production technology or other a variety of causes, all short circuits or open circuit of all signal wires that grid and source electrode may occur connecting, when adding drive voltage signal, full wafer LCD panel is all put and is not worked, and blank screen promptly occurs; Certain row TFT also may occur or connect the drive signal line defectiveness of TFT grid, drive signal that can not be in addition correct to grid causes the grid of whole row not control, thereby signal adds less than on the show electrode, just produces line defect of certain row.Can find when observing that certain row has bright line, illustrates this LCD defectiveness by polaroid; When store electricity perhaps liquid crystal capacitance have defective, time that the back keeps is not enough just may to make certain liquid crystal capacitance not charge or to charge, and causes the error of voltage signal on the show electrode, can find certain bright spot in the time of observation, and this LCD defectiveness also is described.

The utility model content

The purpose of this utility model is to consider the problems referred to above and a kind of TFT LCD programmable combination property electric logging device is provided.

The technical solution of the utility model is: include control module, D/A modular converter, photoelectric coupling switch module, power module, keyboard, wherein control module is connected with D/A modular converter and photoelectric coupling switch module, keyboard respectively, and power module supplies power to control module, D/A modular converter, photoelectric coupling switch module, power module, keyboard respectively.

Above-mentioned control module is single-chip microcomputer U6.

Above-mentioned single-chip microcomputer U6 is single-chip microcomputer Winbond W78E516BP.

Above-mentioned photoelectric coupling switch module comprises photoelectrical coupler U7 and U8.

Above-mentioned photoelectrical coupler U7 and U8 can detect the TLP521-2 of the broken string problem of TFT LCD for realizing exporting EVEN or ODD signal separately, making TFT LCD show single-double-row.

Above-mentioned D/A modular converter is integrated package U9.

Above-mentioned integrated package U9 is D/A converter TLC7225 able to programme.

Above-mentioned power module comprises integrated regulated power supply U1, U2, U3, U4, U5, transistor T 1, T2, and the output end voltage signal GG of T1 collector equals input DC power voltage, by transistor T 1 its break-make of control, as test gating function; V _ComSignal connects common port, by the directly output of power module part; Output terminal EVEN, ODD voltage signal are exactly the voltage signal of control grid.

Above-mentioned integrated regulated power supply U1 is that integrated regulated power supply W7818, integrated regulated power supply U2 are that integrated regulated power supply W7815, integrated regulated power supply U3 are that integrated regulated power supply W7805, integrated regulated power supply U4 are that integrated regulated power supply 78L05, integrated regulated power supply U5 are integrated regulated power supply 78L05.

The above-mentioned keyboard that is connected with control module include by the automatic/hand function button of control module control and before turn over, after turn over some load buttons of function.

The voltage signal of seven kinds of variations of the utility model electric pilot output energy drive TFT LCD, comprise GG, ODD, EVEN, DATA (R), G, voltage signals such as B, produce black, the one-level GTG, the secondary GTG, the ash in class III rank, in vain, red, green, ten pictures such as indigo plant, can detect the blank screen of TFT LCD, defective such as bright spot and bright line, the utility model compared with prior art, have following beneficial effect: (1) can detect the various performance deficiencies of TFT LCD, comprise the bad most of defective that causes of deficient manufacturing procedure and constituent material, enter LCD module operation again by the TFT LCD that detects, improve the yield rate of LCM, reduce consumables cost, enhance productivity; (2) the utility model realizes that simply reliability is very high, can reduce the cost of LCD detection in the past, changes the too high situation of cost that in the past detected; (3) the utility model not only can be used for concrete TFT LCD detection, and its principle can also apply to the circuit design of STN/TN type liquid crystal, improves the processing procedure of STN/TN in the past; (4) the TFT LCD industry output value is huge, and the future development space is very big, and its economic benefit and social benefit are bigger; (5) the utility model can be applicable to the TFT LCD of different size different manufacturers under the immovable substantially condition of hardware circuit, reduces the equipment cost of enterprise.The utility model cost is low, show to fall into the rate height, and detection speed is fast, improves the yield rate of LCM, reduces enterprise cost.The utility model is that a kind of design is ingenious, function admirable, convenient and practical TFT LCD programmable combination property electric logging device.

Description of drawings

Fig. 1 is the TFT equivalent circuit diagram of single pixel unit;

Fig. 2 is the second order drive principle synoptic diagram of TFT LCD;

Fig. 3 is the theory diagram of the utility model TFT LCD test circuit;

Fig. 4 is the schematic diagram of the utility model TFT LCD test circuit.

Fig. 5 is the principle schematic of the utility model TFT LCD combination property electric measuring method.

Embodiment

Embodiment:

Theory diagram of the present utility model as shown in Figure 3, include control module 1, D/A modular converter 2, photoelectric coupling switch module 3, power module 4, keyboard 5, wherein control module 1 is connected with D/A modular converter 2 and photoelectric coupling switch module 3, keyboard 5 respectively, and power module 4 supplies power to control module 1, D/A modular converter 2, photoelectric coupling switch module 3, power module 4, keyboard 5 respectively.

Above-mentioned control module 1 is single-chip microcomputer U6.

Above-mentioned photoelectric coupling switch module 3 comprises photoelectrical coupler U7 and U8.

Above-mentioned D/A modular converter 2 is integrated package U9.

Above-mentioned power module 4 comprises integrated regulated power supply U1, U2, U3, U4, U5, transistor T 1, T2, and the output end voltage signal GG of T1 collector equals input DC power voltage, by transistor T 1 its break-make of control, as test gating function; V _ComSignal connects common port, by the directly output of power module part; Output terminal EVEN, ODD voltage signal are exactly the voltage signal of control grid.

The above-mentioned keyboard 5 that is connected with control module 1 include by the automatic/hand function button of control module 1 control and before turn over, after turn over some load button KEY1, KEY2, KEY3, the KEY4 of function.

When pressing start button KEY1, the P1.7 port of microprocessor U6 is exported high level, transistor T 1, T2 conducting, and the voltage of T1 collector output+30V makes TFT in running order as the gating signal EN of TFT.The P2.4 of microprocessor U6, P2.5 and P2.6, P2.7 output port are controlled photoelectrical coupler U7 and U8 respectively, make U7 and U8 output high level be+18V, and low level is-the strange grid of TFT of 5V, even grid drive signal G1 and G2.Simultaneously, microprocessor U6 is by port P0.0～P0.7 and P2.0～P2.3 control D/A converter U9, make common port control signal VCOM (fixing) and the total enable signal EN of liquid crystal field effect transistor of U9 output TFT, signal G1, G2, source signal S1, S2, test signals such as S3, gating field effect transistor during the EN high voltage wherein, thereby make the short circuit respectively of all source signal lines and signal line, pass through signal G1 and the G2 grid of the strange/idol row field effect transistor of gating liquid crystal matrix respectively more respectively, while source signal S1, S2, S3 is applied to the N of liquid crystal matrix more respectively, N+1, the source electrode of N+2 (N is a natural number) row, thereby the frame of realizing the monoblock liquid crystal drives, timing variations by test waveform, can simulate the practical application picture of LCD module, as GTGs at different levels, liquid crystal matrix is very capable, liquid crystal matrix idol row, liquid crystal matrix very is listed as, liquid crystal matrix idol row, red, green, pictures such as indigo plant, thereby the picture by the simulation practical application shows the various defectives that LCD shields, and comprises the bad many defectives that cause of bad and starting material of processing procedure.

The characteristics of the SCM Based drive voltage signal that can change of the utility model, can be as long as update routine can reach the TFTLCD requirement of test different size different manufacturers under the constant condition of hardware circuit, utilize this instrument that TFT LCD is tested, can occur successively deceiving, ten different pictures such as one-level GTG, secondary GTG, ash in class III rank, white, single file, duplicate rows, red, green, blue, can point not worked and have the TFT LCD of defectives such as bright spot bright line or Show Color be incorrect to pick out.

The utility model is manufactured corresponding test probe according to the TFT LCD of different manufacturers different size, and adds suitable backlight and polaroid, and connecting power supply can test TFT LCD.

Claims

1. TFT LCD programmable combination property electric logging device, it is characterized in that including control module (1), D/A modular converter (2), photoelectric coupling switch module (3), power module (4), keyboard (5), wherein control module (1) is connected with D/A modular converter (2) and photoelectric coupling switch module (3), keyboard (5) respectively, and power module (4) supplies power to control module (1), D/A modular converter (2), photoelectric coupling switch module (3), power module (4), keyboard (5) respectively.

2. TFT LCD programmable combination property electric logging device according to claim 1 is characterized in that above-mentioned control module (1) is single-chip microcomputer U6.

3. TFT LCD programmable combination property electric logging device according to claim 1 is characterized in that above-mentioned single-chip microcomputer U6 is single-chip microcomputer Winbond W78E516BP.

4. TFT LCD programmable combination property electric logging device according to claim 1 is characterized in that above-mentioned photoelectric coupling switch module (3) comprises photoelectrical coupler U7 and U8.

5. TFT LCD programmable combination property electric logging device according to claim 1, it is characterized in that above-mentioned photoelectrical coupler U7 and U8 for realizing exporting EVEN or ODD signal separately, making TFT LCD show single-double-row, can detect the TLP521-2 of the broken string problem of TFT LCD.

6. TFT LCD programmable combination property electric logging device according to claim 1 is characterized in that above-mentioned D/A modular converter (2) is integrated package U9.

7. TFT LCD programmable combination property electric logging device according to claim 1 is characterized in that above-mentioned integrated package U9 is D/A converter TLC7225 able to programme.

8. TFT LCD programmable combination property electric logging device according to claim 1, it is characterized in that above-mentioned power module (4) comprises integrated regulated power supply U1, U2, U3, U4, U5, transistor T 1, T2, the output end voltage signal GG of T1 collector equals input DC power voltage, by transistor T 1 its break-make of control, as test gating function; V _ComSignal connects common port, by the directly output of power module part; Output terminal EVEN, ODD voltage signal are exactly the voltage signal of control grid.

9. TFT LCD programmable combination property electric logging device according to claim 8 is characterized in that above-mentioned integrated regulated power supply U1 is that integrated regulated power supply W7818, integrated regulated power supply U2 are that integrated regulated power supply W7815, integrated regulated power supply U3 are that integrated regulated power supply W7805, integrated regulated power supply U4 are that integrated regulated power supply 78L05, integrated regulated power supply U5 are integrated regulated power supply 78L05.

10. TFT LCD programmable combination property electric logging device according to claim 1, it is characterized in that the above-mentioned keyboard (5) that is connected with control module (1) include by the automatic/hand function button of control module (1) control and before turn over, after turn over some load buttons (KEY1, KEY2, KEY3, KEY4) of function.