JP2002040072A - Inspection device and inspection method for electro- optical device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inspection device and inspection method for electro- optical device for efficiently performing the reliability test and/or burning (screening) inspection of a liquid crystal panel in a short time without affecting on a subject to be inspected. SOLUTION: An acceleration drive signal whose generation interval is shorter than the repeat period of a synchronous signal used in a general using state is generated in the drive circuit of an electro-optical device to be inspected, and the acceleration drive signal is supplied to the drive circuit of the electro- optical device to be inspected. Since the operation frequency of a data line drive circuit and the operation frequency of a scanning line drive circuit can be accelerated and driven about 21 times and about 200 times, respectively, in an XGA liquid crystal panel with 12 parallel input of video signals, the confirmation of reliability and the grasping of life can be performed in a short time in the evaluation for reliability such as life or the like of the liquid crystal panel. The burning (screening) inspection can be efficiently performed in a short time.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an inspection apparatus and an inspection method for an electro-optical device including a liquid crystal display device.

[0002]

2. Description of the Related Art In a manufacturing process of a liquid crystal display device, which is a kind of electro-optical device, a reliability test and a burning (screening) test are performed in order to ensure product quality.

In a reliability test, a product is operated for a long time under a predetermined driving condition under a predetermined environment in which temperature, humidity, and the like are programmed, and the reliability of the liquid crystal panel (element) such as the life and display quality is evaluated. To evaluate.

[0004] Burning (screening) inspection is generally performed at a stage near the end of the manufacturing process of a product in order to detect a defect that does not appear if it has not been operated for a while. Specifically, in order to display a predetermined display pattern for a predetermined period of time and to perform an energizing operation, and to detect an initial defect such as a display abnormality, a line defect, or burn-in due to an abnormality of a transistor or the like of a drive circuit included in the product. Is being done. In order to provide acceleration, current is often supplied in an environment of about 60 ° C.

In the conventional reliability test, a liquid crystal panel is operated for a long time under a normal driving condition in which the liquid crystal panel is actually used as a product, and the reliability such as the life of the panel (element) is evaluated. In the conventional burning (screening) inspection, an energization operation is continuously performed for a predetermined time under a normal driving condition in which the liquid crystal panel is actually used as a product, and an initial failure is inspected. According to the conventional method, in order to confirm long-term reliability and grasp product life in reliability tests,
It took thousands of hours. In addition, there is a possibility that an initial failure cannot be detected due to a short energization time in the burning inspection. In particular, this problem becomes remarkable for the Y-side shift register whose clock frequency is lower than that of the X-side shift register.

[0006]

According to the conventional reliability test method performed under normal driving conditions, it takes thousands of hours to obtain test results and many months.

Therefore, it is conceivable to accelerate the test. However, in a reliability test, as is used in a normal acceleration test, simply increasing the frequency of a clock for driving a shift register of a liquid crystal panel increases the frequency. Even if it is doubled, it is only doubled, and the number of times of switching cannot be increased at an accelerated rate. Attempts to accelerate by several tens of times have a problem that the load on the external drive circuit increases and the frequency range is such that the liquid crystal panel itself does not operate.

Further, this method also has a problem that the product life is sharply shortened.

In order to make the burning (screening) inspection more accurate, one of the countermeasures is to simply lengthen the energizing time. However, this method is limited in the number of manufacturing steps. As with the reliability test,
It is also difficult to accelerate the test simply by increasing the clock frequency. It is conceivable to increase the clock frequency of the Y-side shift register, but the writing of charges to the pixels of the liquid crystal panel becomes irregular, DC is applied, and the polarity cannot be inverted. It can be considered that there is an adverse effect of making a defect such as.

A shift register built in a liquid crystal panel has a bidirectional scan (a front type and a rear type are available as projector types. In the case of a front type, two types of installation methods, a floor-standing type and a ceiling-hanging type, are available. The LCD panel for projectors has a function to select the scanning direction.) If only one direction is used, it is not enough for inspection. It is necessary to switch and drive.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and efficiently performs a reliability test and / or a burning (screening) test of an electro-optical device in a short time without adversely affecting a test object. It is an object to provide an inspection device and an inspection method for the same.

[0012]

An inspection apparatus for an electro-optical device according to the present invention is an acceleration driving signal generator for generating an acceleration driving signal whose generation interval is shorter than a repetition period of a synchronization signal used in a normal use state. And supplying an acceleration drive signal to a drive circuit of the electro-optical device to be inspected.

[0013] Preferably, the acceleration drive signal generator includes:
A plurality of horizontal start pulses are generated within one horizontal scanning period.

Preferably, the acceleration drive signal generator includes:
A plurality of vertical start pulses are generated within one vertical scanning period.

Preferably, the drive circuit of the electro-optical device includes a bidirectional shift register, and further includes a shift direction switch for generating a shift direction switching signal for the bidirectional shift register, wherein the shift direction switch is After the bidirectional shift register performs scanning for a predetermined time or a predetermined number of times, the shift direction is switched.

Preferably, a normal drive signal generator for generating a drive signal used in a normal use state, and one of an output of the normal drive signal generator and an output of the acceleration drive signal generator is selected. The switching device includes a switch for outputting to a drive circuit of the electro-optical device, and a switching signal generator for generating a switching signal for switching the switch.

Preferably, the switching signal generator first selects the output of the acceleration driving signal generator, and then selects the output of the normal driving signal generator.

According to the method of inspecting an electro-optical device according to the present invention, an acceleration drive signal having a shorter generation interval than a repetition period of a synchronization signal used in a normal use state is generated, and the acceleration drive signal to be inspected is generated. It is characterized in that it is supplied to a drive circuit of an optical device.

Preferably, the acceleration drive signal is generated by generating a plurality of horizontal start pulses within one horizontal scanning period.

Preferably, the acceleration drive signal is generated by generating a plurality of vertical start pulses within one vertical scanning period.

Preferably, the driving circuit of the electro-optical device includes a bidirectional shift register, and after the bidirectional shift register performs scanning for a predetermined time or a predetermined number of times, the shift of the bidirectional shift register is performed. A direction switching signal is generated to switch the shift direction.

Preferably, a normal drive signal used in a normal use state is generated, and one of the normal drive signal and the acceleration drive signal is selected and output to a drive circuit of the electro-optical device.

Preferably, the acceleration drive signal is selected first, and then the normal drive signal is selected.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 of the Invention The inspection apparatus / inspection method for a liquid crystal panel according to the first embodiment of the present invention will be described in detail. FIG. 1 is a block diagram showing a state in which a timing signal generation circuit 2 which is a part of an inspection apparatus is connected to a liquid crystal panel 1 to be inspected. FIG. 2 is a block diagram showing an internal configuration of the timing signal creation circuit 2. FIG. 3 is a timing chart in the case of normal driving. FIG. 4 is a timing chart in the case of the acceleration drive according to the embodiment of the present invention.

As shown in FIG. 1, the liquid crystal panel 1 includes a scanning line driving circuit 10, a data line driving circuit 11, and a large number of pixels 12 driven by these. The data line drive circuit 11 receives a test video signal from the inspection device and writes a test video signal to each pixel at a predetermined timing. The scanning line driving circuit 10 is connected to a number of gate lines G1 to Gm. The data line drive circuit 11 is connected to a large number of data lines from S1 to S12 × n. In the example of FIG. 1, since the video signal is input in parallel for 12 dots and transferred to the pixel, in the 1024 × 768 dot XGA panel, n = 1024 {12}.
86, m = 768. The scanning line driving circuit 10 operates by receiving a start signal DY, a clock signal CLY, and its negative logic signal / CLY from the timing signal generation circuit 2. The data line driving circuit 11 receives the start signal DX, the clock signals CLX, and / CL from the timing signal generation circuit 2.
It operates upon receiving X. The scanning line driving circuit 10, the data line driving circuit 11, and the large number of pixels 12 will be described in more detail with reference to FIGS.

In FIG. 5, the liquid crystal device includes, as peripheral circuits, a data line driving circuit 101 for supplying a data signal to the data line 35, a scanning line driving circuit 104 for supplying a scanning signal to the scanning line 32, and A precharge signal NRS of a predetermined voltage level is applied to the plurality of data lines 35 by the image signals Sl, S2,.
..Precharge circuit 201 for collectively supplying prior to Sn
And a sampling circuit 301 for sampling the image signals Sl, S2,..., Sn and supplying them to the plurality of data lines 35, respectively.

The scanning line driving circuit 104 applies the scanning signals Gl, G2,..., Gm to the scanning line 32 at a predetermined timing based on the power supplied from the external control circuit, the reference clock CLY and its inverted clock, and the like. The pulses are applied in a line-sequential manner.

The data line driving circuit 101 generates scanning signals G1 and G based on power supplied from an external control circuit, a reference clock CLX and its inverted clock, and the like.
2,..., Gm, the sampling circuit drive signals X1, X2,. It is supplied at a predetermined timing via 306.

The precharge circuit 201 includes, for example, a TFT 202 as a switching element for each data line 35, a precharge signal line 204 connected to the drain or source electrode of the TFT 202, and a precharge circuit drive signal line. 206 is connected to the gate electrode of TFT202. In operation, power of a predetermined voltage required for writing the precharge signal NRS is supplied from an external power supply via a precharge signal line 204, and each data line 35 is supplied via a precharge circuit drive signal line 206. About the image signals Sl, S
The precharge circuit drive signal NRG is supplied from an external control circuit so that the precharge signal NRS is written at a time prior to the timing of 2,..., Sn. The precharge circuit 201 preferably has an image signal S of an intermediate gradation level.
A precharge signal NRS (image auxiliary signal) corresponding to l, S2,..., Sn is supplied.

The sampling circuit 301 includes a TFT 302 for each data line 35, an image signal line 304 is connected to the source electrode of the TFT 302, and a sampling circuit driving signal line.
306 is connected to the gate electrode of the TFT 302. And
Via the image signal line 304, the image signals S1, S2,..., Sn
Are input, these are sampled. That is, the sampling circuit driving signals X1, X2,... From the data line driving circuit 101 via the sampling circuit driving signal line 306.
, Xn are input, the image signals Sl, S2,..., Sn are sequentially applied to the data lines 35 for each of the image signal lines 304.

In this figure, the data lines 35 are selected one by one. However, as described above, the data lines 35 may be selected in groups of plural lines.

As shown in FIG. 6, the data line driving circuit 101
Has a selection time t1 per pixel.
(Dot frequency) is input as a reference for horizontal scanning. When a transfer start signal DX is input, sampling circuit drive signals X1, X2,... Are sequentially supplied from this shift register. You. In each horizontal scanning period, a precharge circuit drive signal (NRG) is supplied to the precharge circuit 201 at a timing prior to the input of the transfer start signal DX. More specifically, the clock signal CLY, which is used as a reference for vertical scanning, changes (becomes a high level in this figure) and the image signal V
After the polarity of the ID is inverted with respect to the voltage center value of the signal (VID center), the precharge circuit drive signal (NRG) changes to a high level after a lapse of time t3 which is a margin from the polarity inversion to the precharge. Is done. On the other hand, the precharge signal (NRS) is set to a predetermined level having the same polarity as the image signal (VID) during the horizontal retrace period in response to the inversion of the image signal (VID). Therefore, the precharge is performed at the time t2 when the precharge circuit drive signal (NRG) is set to the high level. Then, the precharge circuit drive is performed before time t4 before the end of the horizontal blanking period and the start of the effective display period, that is, by setting the margin from completion of precharge to writing of an image signal as time t4. The signal (NRG) is at a low level. As described above, the precharge circuit 201 collectively supplies the precharge signal (NRS) to the plurality of data lines 35 prior to the image signal in each horizontal blanking period.

As shown in FIG. 2, the timing signal generating circuit 2 includes generators 21 and 22 for generating clock signals CLX and CLY, and inverters 23 and 24 for generating inverted signals / CLX and / CLY. Generators 25 and 28 for generating normal start signals DX and DY, and acceleration start signals DX and D for performing acceleration driving.
It has acceleration signal generators 26 and 29 for generating Y, and switches 27 and 30 for switching and outputting a normal start signal and an acceleration start signal.

Next, the operation of the liquid crystal panel inspection apparatus according to Embodiment 1 of the present invention will be described.

When performing a normal test, the switches 27 and 30 of the timing signal generation circuit 2 select the outputs of the normal DX generator 25 and the normal DY generator 28, respectively, and select the data line driving circuit 11 and the scanning line driving circuit. Each is supplied to the circuit 10.

FIG. 3A is a timing chart of data line driving in the case of normal driving. Start pulse DX,
Pulses are sequentially generated at X1 to X86 and G1 to G768 based on DY. When pulses are generated at the last X86 and G768, start pulses DX and DY are supplied again. The number of times of switching of the X1 output from L → H → L is one in one horizontal scanning period. FIG. 3B shows a timing chart of scanning line driving in the case of normal driving. G1
The number of times of switching from L to H to L of the output is one in one vertical scanning period.

In the case of the normal driving, a normal image, for example, a predetermined test pattern such as a window or a raster of an intermediate gradation level is displayed on the liquid crystal display device 1 to be inspected. It is determined whether the scanning line driving circuit 10 and the data line driving circuit 11 operate correctly or not.

Next, when performing the acceleration test according to the first embodiment of the present invention, the switch 2 of the timing signal generation circuit 2
7 and 30 select the outputs of the accelerating DX generator 26 and the accelerating DY generator 29, respectively, and supply them to the data line driving circuit 11 and the scanning line driving circuit 10, respectively.

FIG. 4A is a timing chart of data line driving in the case of acceleration driving. Start pulse DX,
Pulses are sequentially generated at X1 to X86 and G1 to G768 based on DY. This is the same as in the case of normal driving. However, in the case of acceleration driving, the start pulses DX,
DY occurs repeatedly at much shorter intervals. In the figure, DX and DY occur once in two clock cycles. This indicates a driving state in which the number of times of switching is the largest.

Next, how the number of times of pulse generation increases will be discussed. First, the data line driving circuit will be discussed. In the case of normal driving, as described above, X1,.
Is L → H → L only once in each horizontal scanning period. That is, the corresponding register operates only once in one horizontal scanning period. On the other hand, in the case of acceleration driving, FIG.
As shown in (a), it operates once every two CLX cycles.
When 12 video signals are input on the XGA panel, X1,.
Since the pulse width of ・ corresponds to 12 dots, the corresponding register is 1024 ÷ 12 ÷ 4 = 21.
It operates 33 ≒ 21 times. That is, in the case of the acceleration driving, the register in the data line driving circuit 11 is driven about 21 times as frequently as the normal driving.

Next, the scanning line driving circuit will be discussed.
As in the case of the data line driving circuit, each of G1,... Becomes L → H → L only once in one vertical scanning period. On the other hand, in the case of acceleration drive, as shown in FIG.
It operates once every two cycles of LY. In the case of the XGA panel, since there are 768 rows, the corresponding register operates 768 ÷ 4 = 192 ≒ 200 times in one vertical scanning period. That is, in the case of the acceleration driving, the register of the scanning line driving circuit 10 is driven about 200 times as frequently as the normal driving.

FIG. 4 is an example. For example, CLX, C
DX, DY may be generated once every 3, 4,... Cycle of LY. In short, DX and DY may be generated more frequently than usual. Also in this case, acceleration driving can be realized. However, DX must satisfy the setup time condition and hold time condition for CLX. This is to ensure that the shift register takes in data (sample and hold). Similar considerations are needed for DY and CLY.

When the acceleration driving according to the first embodiment of the present invention is used, the data line driving circuit of the liquid crystal panel can be operated about 21 times and the scanning line driving circuit about 200 times as frequently as the normal driving. Therefore, when evaluating the reliability such as the life of the liquid crystal panel, the reliability can be confirmed and the life can be grasped in a short time. Further, in the burning (screening) inspection for inspecting the initial failure by continuously operating the liquid crystal panel for a predetermined time, the initial failure can be detected in a short conduction time.

In the case where the acceleration drive according to the first embodiment of the present invention is performed, as shown in FIG.
A pulse is simultaneously generated at X9,..., X85. Similarly, (X2, X6, X10, ..., X86),
(X3, X7, X11, ..., X83), (X4, X
, X12,..., X84). That is, a pulse is always supplied simultaneously to 21 to 22 sampling circuit drive signal lines, and 252 to 264
The video signal is supplied to the data lines at the same time. As for the scanning line driving circuit, as shown in FIG. 4B, pulses are simultaneously generated in G1, G5, G9,..., G765. Similarly, (G2, G6, G1
0,..., G766), (G3, G7, G11,...)
, G767), (G4, G8, G12, ..., G7)
At 68), pulses are simultaneously generated. That is, always 1
A scanning signal is simultaneously supplied to 92 scanning lines, and 192 lines of images are selected at the same time.

As described above, when the acceleration drive is performed (the same applies to the case where the data line drive circuit and the scan line drive circuit are separate or simultaneous), the number of data lines to which video signals are supplied simultaneously increases, and Are selected at the same time, and the same video signal is supplied to a plurality of pixels. Therefore, the normal driving method of the pixels is not used, and the display pattern is not originally displayed on the liquid crystal panel. In addition, since the video signal is simultaneously written to a plurality of pixels, the load capacity of the pixels increases, and the pixels cannot be sufficiently charged, resulting in a display image with low contrast (intermediate gradation).

However, since the operations of the data line driving circuit and the scanning line driving circuit are synchronized, the writing of electric charges to the pixels maintains regularity. That is, the polarity of the charge written to the pixel is exactly inverted, and no DC voltage is applied to the liquid crystal, so that there is no adverse effect on the liquid crystal panel. The acceleration driving method according to the first embodiment of the present invention
Since the purpose is to inspect or evaluate the reliability of the data line driving circuit and the scanning line driving circuit, writing to pixels and display images (patterns and gradation levels) are usually performed unless the liquid crystal panel is adversely affected. There is no problem even if it is different from driving.

Embodiment 2 of the Invention Embodiment 2 of the invention
The inspection apparatus / inspection method for a liquid crystal panel will be described.
FIG. 7 is a block diagram showing a state in which the timing signal generation circuit 2 and the shift direction switching circuit 3 which are part of the inspection device are connected to the liquid crystal panel 1 with a bidirectional shift function to be inspected. FIG. 8 is an explanatory diagram of an inspection apparatus / inspection method according to Embodiment 2 of the present invention.

As shown in FIG. 7, the liquid crystal panel 1 includes a scanning line driving circuit 10, a data line driving circuit 11, and a number of pixels 12 driven by these circuits. The data line drive circuit 11 receives a test video signal from the inspection device and writes a test video signal to each pixel at a predetermined timing. The scanning line driving circuit 10 is connected to a number of gate lines G1 to Gm. The data line drive circuit 11 is connected to a large number of data lines from S1 to S12 × n. In the example of FIG. 1, since the video signal is input in parallel for 12 dots and transferred to the pixel, in the 1024 × 768 dot XGA panel, n = 1024 {12}.
86, m = 768. The scanning line driving circuit 10 operates by receiving a start signal DY, a clock signal CLY, and its negative logic signal / CLY from the timing signal generation circuit 2. The data line driving circuit 11 receives the start signal DX, the clock signals CLX, and / CL from the timing signal generation circuit 2.
It operates upon receiving X. The scanning line driving circuit 10 and the data line driving circuit 11 receive shift direction switching signals DIRY and DIRX from the shift direction switching circuit, respectively, and control the shift direction.

The scanning line driving circuit 10 has a so-called bidirectional shift register, and a predetermined pulse width is supplied from the bidirectional shift register based on a power supply voltage, a Y shift clock, a Y shift start pulse, a control signal, and the like. And a row scanning signal at a predetermined timing is generated, and the row scanning signal is applied to the scanning lines in a pulsed manner in a line-sequential manner.

Here, the scanning line drive circuit 10 changes the transfer direction of the bidirectional shift register in the forward direction according to the shift direction switching signal (digital signal having two logical values of H level and L level) included in the control signal. Or by fixing in the opposite direction, it is configured to be able to sequentially supply the scanning signals in order from top to bottom or to sequentially supply the scanning signals in order from bottom to top for a plurality of scanning lines. ing.

On the other hand, the data line drive circuit 11 has a bidirectional shift register like the scan line drive circuit 10. The bidirectional shift register performs a shift operation based on an X shift clock, an X shift start pulse, a control signal, and the like. The shift register starts shifting in response to an X start pulse supplied every horizontal scanning period.
The shift operation is performed in synchronization with the shift clock.

Next, the operation of the scanning line driving circuit 10 will be described.

First, as the first case, when the level of the shift direction switching signal DIRY is fixed to one, the shift direction in a bidirectional shift register (not shown) is fixed to one.

On the other hand, when the level of the shift direction switching signal DIRY is fixed to the other in the second case, the shift direction in the bidirectional shift register is fixed in the opposite direction to the above-described first case.

As described above, the scanning signals are sequentially supplied to the scanning lines by the scanning line driving circuit 10 based on the transfer signals sequentially output from each stage of the bidirectional shift register.

When the above-described acceleration drive is performed on the scanning line driving circuit 10 and the data line driving circuit 11 having such a bidirectional shift function, the first method is to perform a more complete inspection.
It is necessary to perform the acceleration drive in both the shift direction and the second shift direction. The following method can be considered as a method of switching the shift direction during acceleration driving.

Using a shift direction switching circuit 3 including a timer circuit or a counter circuit, the shift direction switching signals DIRX and DIRY of the shift register are automatically set to Hi / L after a predetermined time or after a predetermined number of shift operations.
Make sure that o switches. Using this shift direction switching circuit 3, both forward and reverse shift operations are performed during the energization test. The shift direction switching circuit 3 includes a timer circuit or a counter circuit, and switches DIRX and DIRY at regular intervals or according to a test schedule. For example, as shown in FIG. 8A, when a test schedule is set to perform acceleration driving for a predetermined number of times or time T, a signal is switched when the specified acceleration driving is completed. Then, similar acceleration driving is performed thereafter. According to this procedure, it is possible to reliably execute the predetermined acceleration drive in both the forward and reverse directions.

Alternatively, there is a method of performing a switching operation in both scanning directions during acceleration driving. For example, FIG.
As shown in (b), when the motor is accelerated, DI
Switching between RX and DIRY is repeatedly performed at certain time intervals or every number of shift operations. According to this procedure, the directions are frequently switched, so that all the actual use states of the liquid crystal panel can be reproduced, and all the driving circuits 10 and 11 can be efficiently operated and inspected.

In the example of FIG. 8, the switching of the scanning direction is synchronized with the start timing of the acceleration driving. However, the switching is not limited to this, and may be performed asynchronously.

Embodiment 3 of the Invention Third Embodiment of the Invention
The inspection apparatus / inspection method for a liquid crystal panel will be described.
When the display inspection such as burn-in is simultaneously performed by continuously displaying a specific pattern on the liquid crystal panel for a certain period of time, a desired pattern is not displayed if only the acceleration driving is used, as described in the first embodiment of the invention. It is also necessary to perform normal driving. It is desirable that the switching between the acceleration drive and the normal drive be performed automatically during energization.

FIG. 9 shows a liquid crystal panel 1 to be inspected, a timing signal generation circuit 4, an acceleration drive signal generation circuit 5, a switching circuit 6, a switching circuit 6, a timer circuit, a counter circuit, and the like, which are part of the inspection apparatus. FIG. 2 is a diagram to which a signal generator 7 is connected. The liquid crystal panel 1 is the same as that described in the first embodiment of the invention. FIGS. 10 and 11 are explanatory diagrams of an inspection apparatus / inspection method according to Embodiment 3 of the present invention.

In FIG. 9, the timing signal generation circuit 4
Are the clock signals CLX, / CLX, CLY, / CLY
Then, start signals DX1 and DY1 for normal driving are generated. On the other hand, the acceleration driving signal generation circuit 5 generates start signals DX2 and DY2 for acceleration driving.
The switching circuit 6 selects one of the signals DX1 and DX2 and one of the signals DY1 and DY2 and supplies the selected signal to the liquid crystal panel 1 to be inspected. The timing signal creation circuit 4 corresponds to 21, 22, 25, and 28 in FIG. 2, and the acceleration drive signal creation circuit 5 corresponds to 26 and 29 in FIG. The switching circuit 6 corresponds to 27 and 30 in FIG.

The third embodiment of the present invention is characterized in that the driving is automatically switched from the acceleration driving to the normal driving after a predetermined time by using a timer circuit or a counter circuit. In the inspection process, a display inspection such as burn-in may be performed by continuously displaying a specific pattern on the liquid crystal panel for a certain period of time.
For example, a pattern as shown in FIG. However, if acceleration driving is performed, the desired pattern shown in FIG. 11A cannot be obtained. For example, when the X side is accelerated, the screen flows horizontally as shown in FIG. 11B, and when the Y side is accelerated, the screen flows vertically as shown in FIG. 11C. Fig. 11 shows that both Y are accelerating at the same time.
The entire surface becomes gray as shown in (d).

In the case of performing such a display inspection, in order to inspect the influence of the display pattern after the end of energization, it is necessary to perform acceleration driving for a short time, and then switch to normal driving and energize in a predetermined pattern for a predetermined time. desirable. Inspection of the drive circuit is considered to be sufficient in a short time because the number of switchings is drastically increased by the acceleration drive. For example, the inspection is performed according to a schedule as shown in FIG. In accordance with this schedule, the switching signal generator 7 outputs a switching signal as shown in FIG.

The third embodiment of the present invention can be applied to the inspection of the liquid crystal display device with a bidirectional shift function according to the second embodiment of the present invention. A shift direction switching circuit 3 is added to the timing signal generation circuit 4 to the switching signal generator 7 shown in FIG. The shift direction switching circuit 3 is, for example, as shown in FIG.
As shown in (b), the forward direction and the reverse direction are switched in each of the acceleration drive and the normal drive. In each drive, switching between the forward direction and the reverse direction may be repeated several times.

According to the third embodiment of the present invention, it is possible to automatically shift to the display inspection energization after the drive circuit inspection energization. Inspection of the drive circuit can be efficiently performed in a short time by accelerated driving, and display inspection can be appropriately performed in normal driving.

By performing the accelerated driving described above, in the reliability test, the reliability and life of the shift register can be grasped in a short period of time, which facilitates rationalization and shortens the development period. The life under actual use conditions can be estimated based on how many times acceleration actually takes place.

In the burning inspection, a defect can be detected efficiently with a limited energization time (restriction on man-hours in the manufacturing process).
Improve customer satisfaction.

The driving method of the present invention can be realized simply and inexpensively without any load on the performance and scale of the external circuit, the performance and characteristics of the liquid crystal panel.

Further, by switching the bidirectional scanning, inspection can be performed under conditions close to actual use conditions, and the defect detection ability is improved. Further, the inspection process can be rationalized.

By switching between the acceleration drive and the normal drive, the above-described effects can be obtained without impairing the effects of the conventional inspection method, and the defect detection capability and the rationalization of the inspection process can be further improved.

The apparatus / method according to the embodiment of the present invention has an advantage that it can be realized simply and inexpensively.

The present invention is not limited to the above embodiments, and various modifications can be made within the scope of the invention described in the claims, and these are also included in the scope of the present invention. Needless to say, this is done.

In this specification, means does not necessarily mean physical means, but also includes a case where the function of each means is realized by software.
Further, the function of one unit may be realized by two or more physical units, or the function of two or more units may be realized by one physical unit.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of an inspection device / inspection method for a liquid crystal panel according to a first embodiment of the present invention.

FIG. 2 is a block diagram illustrating an internal configuration of a timing signal generation circuit according to the first embodiment of the present invention;

FIG. 3 is a timing chart in the case of normal driving.

FIG. 4 is a timing chart in the case of acceleration driving according to the first embodiment of the present invention.

FIG. 5 is a diagram showing an internal configuration of a liquid crystal panel.

FIG. 6 is an operation timing chart of the liquid crystal panel.

FIG. 7 is an explanatory diagram of an inspection device / inspection method for a liquid crystal panel according to a second embodiment of the present invention.

FIG. 8 is a timing chart of the inspection apparatus / inspection method according to the second embodiment of the present invention.

FIG. 9 is an explanatory diagram of an inspection device / inspection method for a liquid crystal panel according to Embodiment 3 of the present invention.

FIG. 10 is a timing chart of an inspection apparatus / inspection method according to Embodiment 3 of the present invention.

FIG. 11 is an explanatory diagram of a display inspection pattern and a screen during acceleration driving.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Liquid crystal panel 2 Timing signal creation circuit 3 Shift direction switching circuit 4 Timing signal creation circuit 5 Acceleration drive signal creation circuit 6 Switching circuit 7 Switching signal generator 10 Scan line drive circuit 11 Data line drive circuit 12 Pixel

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G09G 3/20 623 G09G 3/20 623P 623H 670 670Q 3/36 3/36 F term (Reference) 2G036 AA27 BA38 CA07 2H088 FA12 FA13 FA30 HA08 MA20 2H093 NA16 NA43 NA45 NC16 NC22 NC23 ND50 5C006 AA02 AB01 AC11 AC24 AF23 BB16 EB01 FA04 FA20 5C080 AA10 BB05 DD15 EE26 FF11 GG02 JJ01 JJ02 JJ04

Claims (12)

[Claims] 1. An electro-optical device according to claim 1, further comprising: an acceleration drive signal generator for generating an acceleration drive signal having an interval shorter than a repetition period of a synchronization signal used in a normal use state. An inspection device for an electro-optical device, which is supplied to a driving circuit. 2. The inspection apparatus for an electro-optical device according to claim 1, wherein the acceleration driving signal generator generates a plurality of horizontal start pulses within one horizontal scanning period. 3. The inspection apparatus according to claim 1, wherein the acceleration drive signal generator generates a plurality of vertical start pulses within one vertical scanning period. 4. The driving circuit of the electro-optical device includes a bidirectional shift register, and further includes a shift direction switch that generates a switching signal of a shift direction of the bidirectional shift register, wherein the shift direction switch includes: 2. The inspection apparatus for an electro-optical device according to claim 1, wherein the shift direction is switched after the bidirectional shift register performs scanning for a predetermined time or a predetermined number of times. 5. A normal drive signal generator for generating a drive signal used in a normal use state, and selecting one of an output of the normal drive signal generator and an output of the acceleration drive signal generator to select the electric signal. The inspection apparatus for an electro-optical device according to claim 1, further comprising: a switch for outputting to a drive circuit of the optical device; and a switch signal generator for generating a switch signal for switching the switch. 6. The switching signal generator according to claim 5, wherein the output of the acceleration drive signal generator is selected first, and then the output of the normal drive signal generator is selected.
An inspection apparatus for an electro-optical device according to claim 1. 7. An accelerating drive signal whose generation interval is shorter than a repetition period of a synchronizing signal used in a normal use state is generated, and the accelerating drive signal is supplied to a drive circuit of an electro-optical device to be inspected. A method for inspecting an electro-optical device. 8. The method according to claim 7, wherein the acceleration drive signal is generated by generating a plurality of start pulses in a horizontal direction within one horizontal scanning period. 9. The inspection method for an electro-optical device according to claim 7, wherein the acceleration drive signal is generated by generating a plurality of vertical start pulses within one vertical scanning period. 10. The driving circuit of the electro-optical device includes a bidirectional shift register, and after the bidirectional shift register performs scanning for a predetermined time or a predetermined number of times, a shift direction of the bidirectional shift register. 9. The inspection method for an electro-optical device according to claim 8, wherein the switching direction is switched by generating the switching signal of (1). 11. A normal drive signal used in a normal use state is generated, and one of the normal drive signal and the acceleration drive signal is selected and output to a drive circuit of the electro-optical device. The method for inspecting an electro-optical device according to claim 7. 12. The method according to claim 11, wherein the acceleration drive signal is selected first, and then the normal drive signal is selected.