JP2010160383A - Optical characteristic measuring system for display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical characteristics measuring system for a display device, capable of acquiring and storing a large quantity of optical characteristic data in a short, time by automatically altering the measuring angle to the display device. <P>SOLUTION: The optical characteristics measuring system 10 for the display device includes an optical measuring device 17 for measuring the optical characteristics of an image displayed on a liquid crystal display panel 12 and outputting measured data; a turning section 19 for making the liquid crystal display panel 12 turn, at a prescribed angle that corresponds to an inputted angle control signal and a control part 14 for outputting angle control signals corresponding to a plurality of prescribed angles to the turning section 19 and acquiring and storing the measured data from the optical measuring device 17 that are made to correspond to the respective prescribed angles. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

The present invention relates to an optical characteristic measurement system capable of changing a measurement angle with respect to a display device, and in particular, a display capable of automatically acquiring and storing a large amount of optical characteristic data in a short time by automatically changing the measurement angle with respect to the display device. The present invention relates to a system for measuring optical characteristics of an apparatus.

The liquid crystal display panel is light, thin, and has low power consumption compared to a CRT (Cathode Ray Tube), and is therefore used in many electronic devices for display. The relationship between the input voltage and the luminance of the liquid crystal display panel is generally determined by assuming that the γ value is 2.2 and that the luminance is the input voltage due to the convenience of transmission of television broadcasts, the difference in characteristics with the CRT, and the characteristics of the human eye. Is displayed at a brightness of γ. The voltage applied to the liquid crystal display panel is a value according to the gradation,
An image is displayed with a predetermined gradation by controlling the twist amount of the liquid crystal molecules with an analog voltage. The number of gradation levels varies depending on the liquid crystal display panel. For example, there are 128 gradations, 64 gradations, 32 gradations, and the like, which are expressed by 7-bit, 6-bit, and 5-bit digital signals, respectively.

In a liquid crystal display panel, even when a voltage having a predetermined gradation is applied, if the gradation of adjacent subpixels is different, electrical crosstalk may occur, resulting in different brightness. The cause of this electrical crosstalk is that the spikes that occur as the scan line voltage switches,
This is considered to change the effective voltage value applied to the pixel. In particular, in a liquid crystal display panel for two-screen display developed for displaying a stereoscopic image or displaying different images in the driver's seat and the passenger seat, different images are input to adjacent sub-pixels. A lot of typical crosstalk occurs.

For this reason, a liquid crystal display device using a liquid crystal display panel applies a voltage subjected to electrical crosstalk correction to the liquid crystal display panel. This correction method is disclosed in Patent Document 1 below.
As described in the above, the designer obtains, in advance, correction values of all combinations of the gradations of the subpixels to be corrected and the gradations of the adjacent subpixels, and calculates an electrical correction table (hereinafter referred to as LUT (Lookup T
called “Able)” and stored in the EEPROM of the liquid crystal display device. The liquid crystal display device determines the correction value corresponding to the gradation of the correction sub-pixel and the gradation of the adjacent sub-pixel as an electrical LUT.
Is added to the gradation of the correction sub-pixel and output to the liquid crystal display panel.

Further, in a two-screen liquid crystal display panel that displays different images in the first viewing direction and the second viewing direction in a distinguishable manner, a light shielding layer having a slit is used. Crosstalk also occurs. The cause of this optical crosstalk is due to light leakage caused by diffracting light from sub-pixels of the same color of adjacent pixels at the periphery of the slit of the light shielding layer. For this purpose, the designer determines the correction values of all the gradations of the subpixels to be corrected and the gradations of the subpixels of the same color of the adjacent pixels through experiments, creates an optical LUT, and creates an EEPROM of the liquid crystal display device. Remember it. The liquid crystal display reads the correction value corresponding to the gradation of the correction sub-pixel and the gradation of the sub-pixel of the same color of the adjacent pixel from the optical LUT and adds it to the correction sub-pixel gradation to display the liquid crystal display Output to the panel.

Further, as disclosed in Patent Document 2 below, in order to prevent the driver from looking into the image in the passenger seat direction, the first image and the second image are arranged in the first viewing direction and the second viewing direction. A two-screen liquid crystal display device has also been developed in which the slit of the light-shielding layer that displays distinguishably is eccentric. In this two-screen liquid crystal display device, the first viewing direction and the second viewing direction are not symmetrical with respect to the normal of the screen, so an optical LUT is required for each image.

JP 2008-20574 A JP 2006-184860 A JP 2000-221113 A

Liquid crystal display panel developers, quality managers, etc. are looking for optical verification and LUTs.
It is necessary to perform various optical measurements on prototypes and mass-produced liquid crystal display panels. At that time, a developer, a quality manager, or the like uses, for example, an optical measuring instrument that measures luminance and chromaticity (tristimulus values X, Y, Z) as shown in Patent Document 3 above. γ characteristic (brightness value for each gradation)
It is necessary to measure the brightness of the subpixel to be measured when the gradation of adjacent subpixels is different or when the gradation of subpixels of the same color of adjacent pixels is different to obtain the LUT.

However, in the measurement of the γ characteristic, it is necessary to measure the luminance for all the gradations. For example, in the case of 64 gradations, the gradation is changed from 0 gradation to 63 gradations, and each gradation is changed. The brightness had to be measured. In the measurement for acquiring the LUT, it was necessary to acquire the LUT of the 64 × 64 table at 64 gradations. Further, when it is necessary to measure a plurality of sample temperatures under a plurality of environmental temperatures, the number of times of measurement becomes very large. In particular, for a two-screen liquid crystal display panel, it is necessary to add an optical LUT, and a two-view LUT is also necessary, so one month or more is required to obtain a single two-screen liquid crystal display panel. It also took a long time.

The present invention has been made to solve such problems of the prior art, and automatically changes the measurement angle for the display device to store the measurement data so that the measurer can perform optical measurement. It is an object of the present invention to provide an optical characteristic measurement system for a display device that can reduce the time spent for the display.

In order to achieve the above object, an optical property measurement system for a display device according to the present invention is an optical property measurement system for a display device that displays an image, and measures and measures an optical property of an image displayed on the display device. An optical measuring device that outputs the measured data, a rotation unit that rotates the display device to a predetermined angle corresponding to the input angle control signal, and the angle control signal corresponding to a plurality of predetermined angles. And a control unit that acquires and stores measurement data from the optical measuring device in correspondence with the predetermined angles.

The optical characteristic measurement system for a display device according to the present invention includes a rotation unit that rotates the display device to a predetermined angle corresponding to an input angle control signal, and the rotation of the angle control signal corresponding to a plurality of predetermined angles. And a control unit for acquiring and storing the measurement data from the optical measuring device in correspondence with the respective predetermined angles. Thus, according to the optical characteristic measurement system for a display device of the present invention, the measurement angle of the display device can be automatically changed to a predetermined angle by the control unit, and the measurement data can be automatically acquired and stored. Therefore, the time required for measurement can be greatly shortened as compared with the conventional manual measurement method. In addition, when the optical characteristic measurement system for the display device of the present invention is activated, the operator automatically proceeds with the measurement operation until the measurement is completed, so that it is not necessary to continuously monitor the optical characteristic measurement system for the display device. At the same time, human measurement errors can be prevented.

In the optical characteristic measurement system for a display device according to the present invention, the control unit outputs an image pattern having a plurality of different gradations to the display device, and the optical measurement is performed each time the gradation of the image pattern is switched. It is preferable that the measurement data from the device is acquired and stored in correspondence with each measurement angle.

According to the optical characteristic measurement system for a display device of the present invention, optical measurement data corresponding to each gradation and measurement angle can be automatically acquired and stored, so that for measuring γ characteristics at a plurality of angles. Acquisition of data and crosstalk correction tables and flicker
The time spent for data acquisition for countermeasures can be shortened. Note that the present invention can be applied to an image display device such as a CRT, a liquid crystal display device, an organic EL display device, or a plasma display device that performs gradation display.

Further, in the optical characteristic measurement system for a display device of the present invention, the display device further includes a thermostatic chamber for switching and maintaining the display device at a plurality of predetermined temperatures corresponding to the input temperature control signal, It is preferable that the measurement data from the optical measuring device is acquired and stored in correspondence with the respective measurement angles at every predetermined temperature.

According to the optical characteristic measurement system for a display device of the present invention, the measurement data of the display device can be automatically acquired and stored in addition to the temperature condition, so that it is much more than in the case of the conventional manual measurement. Measurement time can be shortened. Especially for in-vehicle display devices, -40 ° C to 8 ° C.
Since quality assurance of 5 ° C. is required, the temperature that must be measured also increases. However, even in such a case, the optical characteristic measurement system of the display device of the present invention automatically changes the temperature to measure data. Therefore, the effect of the present invention is remarkably exhibited.

In the optical characteristic measurement system for a display device according to the present invention, the control unit outputs a plurality of image patterns having different gradations to the display device, and each measurement is performed each time the gradation of the image pattern is switched. It is preferable that measurement data is acquired and stored in correspondence with the angle and temperature.

In the optical characteristic measurement system for a display device of the present invention, the gradation of the image pattern of the display device is automatically changed, and optical measurement data corresponding to the measurement angle and temperature is automatically acquired for each gradation. And memorize it. Therefore, according to the optical characteristic measurement system for a display device of the present invention, measurement data of γ characteristics at a plurality of angles at a predetermined temperature for each gradation, acquisition of a crosstalk correction table, and flicker countermeasures The time spent for data acquisition can be reduced.

In the optical characteristic measurement system for a display device according to the present invention, the control unit performs an optical measurement by changing a provisional crosstalk correction value to be added to a correction target gradation for each gradation of a minimum unit. It is preferable that the temporary crosstalk correction value at which the measurement result is optimized is acquired and stored in correspondence with the respective measurement angles and temperatures.

According to the optical characteristic measurement system for a display device of the present invention, a preferred crosstalk correction value can be automatically acquired and stored in correspondence with each measurement angle and temperature in a predetermined gradation, so that the display device can be stored. The time required to obtain the crosstalk correction data can be greatly shortened.

In the optical characteristic measurement system for a display device according to the present invention, the display device includes a light-shielding film having an opening for displaying the first image and the second image so as to be distinguishable between the first viewing direction and the second viewing direction. It is preferable to have it.

In a two-screen display device having an opening of a light shielding layer (hereinafter referred to as a slit), a thin film transistor (TFT) as a switching element disposed at a corner of a sub-pixel.
Since the display area is asymmetrical because it is necessary to shield the stor portion, the luminance varies depending on the viewing direction. In this case, since it is necessary to measure the luminance for a plurality of viewing directions, it takes a further measurement time. However, according to the optical measuring device of the display device of the present invention, all of these measurements can be automated. The time required for this can be greatly reduced.

Further, as disclosed in Patent Document 2, in a two-screen liquid crystal display device in which a slit is eccentric to prevent the driver from looking into an image in the passenger seat direction, for example, the first viewing direction and the first viewing direction The two viewing directions are not symmetrical with respect to the normal of the screen, and an optical LUT is required for each image. At this time, it is necessary to measure the luminance in a plurality of viewing directions. However, according to the optical measuring device of the display device of the present invention, all of these measurements can be automated, so that the measurement time and the measurer can further measure. It is possible to shorten the time spent in the process.

In the optical characteristic measurement system for a display device of the present invention, the control unit switches the temperature of the thermostatic chamber after finishing measurement at all measurement angles, and outputs a control signal for performing aging for a predetermined time. It is preferable to do.

When the temperature of the constant temperature layer is changed, it takes time until the entire measurement system including the display device reaches a predetermined temperature. According to the optical characteristic measurement system for a display device of the present invention, the temperature of the thermostatic chamber is switched after the measurement at all measurement angles is completed, and a control signal for performing aging for a predetermined time is output. Since time-consuming aging is not performed a plurality of times during measurement at one measurement angle, the number of times of changing the temperature can be reduced, so that the measurement time can be further shortened.

FIG. 1A is a block diagram showing an outline of the optical characteristic measurement system according to the present embodiment, and FIG. 1B is a plan view showing an arrangement relationship between the rotation unit and the optical measurement device. It is a figure which shows the pixel arrangement | sequence of a liquid crystal display panel. FIG. 3A is a diagram showing the cross-sectional shape of the light shielding layer of the two-screen liquid crystal display panel and the principle of image separation of the two screens, and FIG. 3B is a diagram showing a checkered pattern of the light shielding layer. It is a figure which shows the synthesis | combination of 2 screens of a 2 screen liquid crystal display panel. It is a figure which shows generation | occurrence | production of the crosstalk of a 2 screen liquid crystal display panel. It is a block diagram which shows the crosstalk correction | amendment part of the 2 screen liquid crystal display panel in which the liquid crystal display panel of FIG. 2 is integrated. It is a table | surface which shows the electric LUT of FIG. It is a flowchart which shows the example of acquisition of the VT curve using the system of this embodiment. It is a flowchart which shows the example of acquisition of LUT using the system of this embodiment. It is a flowchart which shows the detail of step S38 of FIG. It is a figure which shows generation | occurrence | production of the optical crosstalk by the light-shielding barrier of a 2 screen liquid crystal display panel. It is a block diagram which shows the correction | amendment of the optical crosstalk using the system of this embodiment. It is a figure which shows a viewing direction when the slit of the light-shielding barrier of the 2 screen liquid crystal display panel has shifted | deviated from the center.

The best mode for carrying out the present invention will be described below with reference to the embodiments and drawings. However, the embodiments shown below are not intended to limit the present invention to those described herein. The present invention can be equally applied to various modifications without departing from the technical idea shown in the claims. In each drawing used for the description in this specification, each layer and each member are displayed in different scales so that each layer and each member can be recognized on the drawing. However, it is not necessarily displayed in proportion to the actual dimensions.

FIG. 1A is a block diagram showing an outline of the optical characteristic measurement system according to the present embodiment.
B is a plan view showing an arrangement relationship between the rotating unit and the optical measuring device. FIG. 2 is a diagram showing a pixel arrangement of the liquid crystal display panel. FIG. 3A is a diagram showing the cross-sectional shape of the light shielding layer of the two-screen liquid crystal display panel and the principle of image separation of the two screens, and FIG. 3B is a diagram showing a checkered pattern of the light shielding layer. FIG. 4 is a diagram showing the composition of the two screens of the two-screen liquid crystal display panel. FIG. 5 is a diagram showing the occurrence of crosstalk in the two-screen liquid crystal display panel. FIG. 6 is a block diagram showing a crosstalk correction unit of a two-screen liquid crystal display panel in which the liquid crystal display panel of FIG. 2 is incorporated. FIG. 7 is a table showing the electrical LUT of FIG. FIG. 8 is a flowchart showing an example of acquiring a VT curve using the system of this embodiment. FIG. 9 is a flowchart showing an example of acquiring an LUT using the system of this embodiment. FIG. 10 is a flowchart showing details of step S38 in FIG. FIG. 11 is a diagram illustrating the occurrence of optical crosstalk due to the light-shielding barrier of the two-screen liquid crystal display panel. FIG. 12 is a block diagram showing optical crosstalk correction using the system of this embodiment. FIG.
These are figures which show a viewing direction when the slit of the light-shielding barrier of the 2 screen liquid crystal display panel has shifted | deviated from the center.

The optical characteristic measurement system 10 of the present embodiment includes a liquid crystal display panel 1 in a liquid crystal module 11.
2 is a system for measuring the optical characteristics of 2. As shown in FIG. 1A, the liquid crystal module 11 has a backlight 13 that emits light from the back surface of the liquid crystal display panel 12. The optical characteristic measurement system 10 includes a control unit 14 that controls each unit and, for example, a DVI output from the control unit 14.
(Digital Visual Interface) An image processing circuit 15 that converts a standard image signal into a signal that is compatible with the liquid crystal display panel 12, a backlight drive circuit 16 that drives the backlight 13,
An optical measuring device 17 that measures optical characteristics such as luminance and chromaticity of an image displayed on the liquid crystal display panel 12 and a USB port of the control unit 14 and an RS232C interface of the optical measuring device 17 are mutually converted. 1 IF (interface) 18, a rotation unit 19 that rotatably holds the liquid crystal module 11, and an output signal of the USB port of the control unit 14
The second IF 20 that converts the signal into a CI bus signal, the thermostatic chamber 21 that houses the liquid crystal module 11 and sets the temperature in the bath to a temperature corresponding to the output signal of the control unit 14, and the USB port of the control unit 14 is connected to the thermostatic chamber 21. For example, it has the 3rd IF22 converted into RS-485 interface.

The control unit 14 performs various numerical calculations, information processing, device control, etc. according to a program.
A PU (Central Processing Unit) 23 and a storage circuit 24 for storing data necessary for programs and operations are provided. The rotation unit 19 is an R for rotating the liquid crystal module 11.
A C servo motor 25 is provided. In the optical characteristic measurement system 10 of the present embodiment, as shown in FIG. 1B, the liquid crystal display panel 12 is rotated by the rotation unit 19 so that the optical measuring instrument 17 has a predetermined angle, and the liquid crystal display is performed by the optical measurement device. A predetermined optical characteristic of the panel 12 is measured.

Next, the liquid crystal display panel 12 whose optical characteristics are measured will be described. FIG. 2 is a diagram illustrating pixels of the liquid crystal display panel 12. For example, if the liquid crystal display panel 12 is of the color WVGA standard, it has 800 pixels in the row direction (horizontal direction) and 480 pixels in the column direction (vertical direction). One pixel is composed of three sub-pixels of R (red), G (green), and B (blue), which are the three primary colors of light. As shown in FIG. 3A, the two-screen liquid crystal display panel 12 includes a color filter layer 2
6 has a light shielding layer 27 on the display surface side (upper side in FIG. 3A). The light shielding layer 27 has a structure shown in FIG.
As shown in FIG. 2, the slits 28 are formed in a checkered pattern, for example.

As shown in FIG. 3A, in the two-screen liquid crystal display panel 12, one of the checkered patterns of the sub-pixels can be visually recognized only from the right direction (the driver's seat direction of the right-hand drive car) when viewed from the user. Visible only from the left (passenger seat direction of right-hand drive car). For example, the navigation screen can be viewed in the right direction, and the DVD screen can be viewed in the left direction.

The gradation data of the sub-pixels of the input image is 6 bits, and the luminances of R, G and B are 0.
There are 64 types of gray levels to 63 gray levels. The drive control of the luminance of the liquid crystal display panel 1 is in units of one gradation. That is, a gradation that is not an integer cannot be specified. However, since the period of one screen (800 pixels × 480 pixels), that is, the frame period is as fast as 60 Hz, an afterimage is used,
Four frames are defined as one period, and one frame for increasing one gradation in one period is combined.
FRC (Frame Rate Control) in units of five gradations can also be performed. For example, during a period of 1.75 gradations, if one frame is set to one gradation in four frames of one cycle and the remaining three frames are set to two gradations, it will appear as 1.75 gradations due to an afterimage. .

The image input to the two-screen liquid crystal display panel 12 is a composite image. As shown in FIG. 4, the image includes, for example, an image in the right viewing direction of 800 pixels × 480 pixels and a left viewing direction of 800 pixels × 480 pixels. Are selected in a checkered pattern of subpixels, and one 800 pixel × 480 pixel image is synthesized. When different images are adjacent to each other in this manner, different gradation voltages are applied to adjacent sub-pixels, and electrical crosstalk is likely to occur. For example, as shown in FIG. 5, when the image in the left viewing direction is black in the center of white and the image in the right viewing direction is white, the voltage in the center of the image in the right viewing direction is caused by electrical crosstalk. Will change so it will appear a little gray. The electrical crosstalk occurs not only in the above-described composite image but also when the gradations of adjacent subpixels are different. In particular, in the composite image, the subpixels of different images are adjacent to each other, resulting in a very large crosstalk. . For this reason, in the two-screen liquid crystal display panel 12, it is necessary to correct electrical crosstalk.

FIG. 6 shows a block diagram for correcting electrical crosstalk of the two-screen display device.
In FIG. 6, a solid line indicates the two-screen display device 30, and a broken line indicates the navigation device 50 in which the two-screen display device 30 is incorporated. The two-screen display device 30 displays two source images (navigation image, DVD image) from the liquid crystal display panel 12 and the navigation device 50 as two.
A signal processing circuit 31 for correcting the screen composition and crosstalk and outputting the corrected crosstalk to the liquid crystal display panel 12;
An EEPROM 32 that stores various data necessary for the operation of the signal processing circuit 31 and a power supply circuit 33 that supplies power to the liquid crystal display panel 12 are provided.

The signal processing circuit 31 can display on the liquid crystal display panel 12 a two-screen synthesis unit 34 that synthesizes two source images, a crosstalk correction unit 35 that performs crosstalk correction, and a signal corrected by the crosstalk correction unit 35. Output signal generator 36 for controlling the polarity and timing,
An EEPROM controller 37 that controls input / output of the EEPROM 32 is provided.

The crosstalk correction unit 35 includes a preprocessing unit 38, an electric correction unit 39, and a calculation unit 40. The preprocessing unit 38 sends necessary data from the image signal from the two-screen composition unit 34 to the electrical correction unit 39 and the calculation unit 40. The electrical correction unit 39 has an electrical LUT 41 that stores an electrical correction table (see FIG. 7) from the EEPROM controller 37. The electrical correction unit 39 inputs the sub-pixel data to be corrected and the right-side sub-pixel data from the pre-processing unit 38, and outputs the electrical Electrical correction data is extracted from the electrical correction table of the LUT 41. The calculation unit 40 adds the electrical correction data extracted by the electrical correction unit 39 to the sub image data to be corrected from the preprocessing unit 38.

The EEPROM 32 stores an electrical correction table shown in FIG. The electrical correction table stores electrical correction values of gradations of all adjacent subpixels with respect to gradations of all correction target subpixels. This correction value is a value obtained through experiments. When the power switch (not shown) of the navigation device 50 is turned on, the EEPROM controller 37
The electrical correction table of the OM 32 is transferred to the electrical LUT 41.

The image processing of the two-screen display device 30 having the above configuration will be described. As shown in FIG. 4, the two-screen composition unit 34 has an 800 pixel × 480 pixel navigation image input from the navigation unit 51 of the navigation device 50 and an 800 input from the DVD playback unit 52.
Select a pixel x 480 pixel DVD playback image as a checkered pattern of sub-pixels, and select one 800
An image of pixel × 480 pixels is synthesized. The pre-processing unit 38 of the crosstalk correction unit 35 outputs correction target sub-pixel data (6-bit gradation data) from the composite image input from the two-screen composition unit 34 to the electrical correction unit 39 and the calculation unit 40. The subpixel data on the right is output to the electrical correction unit 39. The electrical correction unit 39 uses the electrical correction table of the electrical LUT 41 to extract electrical correction data of the input correction target sub-pixel data and the right-side sub-pixel data. The calculation unit 40 adds the electrical correction data extracted by the electrical correction unit 39 to the correction target sub-image from the preprocessing unit 38.

As described above, in particular, the two-screen display device 30 requires an electric LUT in order to provide an electric crosstalk correction unit. This value is difficult to obtain by calculation and varies depending on the type of liquid crystal display panel. For this reason, the developer needs to obtain an electrical correction table by experiment for each new model. In the case of 6-bit gradation data, the electric LUT has 64 types of gradations of subpixels to be corrected and 64 kinds of gradations of adjacent subpixels.
X64 = 4096 types. Further, since the luminance in the left and right viewing directions may be different due to factors such as the subpixel display area being not symmetrical, an experiment must be performed in both viewing directions.

Furthermore, since the temperature compensation range of the in-vehicle device is as wide as, for example, −40 ° C. to + 85 ° C., experiments on many temperatures are necessary. In addition, in order to obtain an optimum correction value through experiments, a standard luminance must be obtained in advance. You must also experiment with multiple prototypes. For this reason, this experiment has been performed manually in the past, and it took an enormous number of days to acquire the electrical LUT.

In the optical characteristic measurement system 10 for a display device according to the present embodiment, as shown in FIG. 1A, the CPU 23 executes a program stored in the storage circuit 24 so as to automatically acquire an electric LUT. Hereinafter, a process performed by the CPU 23 will be described. First, the luminance (γ characteristic) for each gradation when the luminance of the sub-pixels on the viewing angle side and the non-viewing angle side is the same is obtained as the standard luminance. FIG. 8 is a flowchart showing the operation of the control unit 14 of FIG. 1, that is, the content of the CPU executing the program stored in the storage circuit 24. The control unit 14 defines variables in advance in an internal register (not shown) (see the upper right column in FIG. 8) (step S10).

Here, red gradation array variable R (0) is 0, R (1) is 1,... R (n) is n,
... R (63) is defined as 63, array variable G (0) for green gradation is 0, G (1) is 1,
... G (n) is defined as n, G (63) is defined as 63, and blue gradation array variable B (0)
Is defined as 0, B (1) is defined as 1, B (n) is defined as n,... B (63) is defined as 63, and the array variable T (2) of the set temperature (° C.) of the thermostat is set to +25. , T (1) is defined as 0, T (0) is defined as −25, the array variable A (2) of the measurement angle (°) is defined as 0, A (1) is defined as +30, and A (0) is defined as −30. Then, the variable A of the aging time (minute) of the thermostat is defined as 90, and the array variable of the standard luminance measured at the set temperature of each thermostat, each measurement angle, and each gradation is represented by K (
0, 0, 0) to K (2, 2, 63).

The control unit 14 sets the initial value of the loop variable i1 for the measurement angle to 2, sets the initial value of the constant-temperature bath temperature loop variable i2 to 2, and sets the initial value of the tone loop variable i3 to 0 (Step S1). S1
1). And the control part 14 controls the motor 25 of the rotation part 19 so that it may become the measurement angle of A (i1) (step S12). Since i1 = 2 at first, the measurement angle is 0 ° (front)
It is. In the two-screen display device, the measurement angle of 0 ° is not the angle at which the user views the image, but since it is necessary to verify the luminance at an unnecessary angle, optical measurement is performed even at the measurement angle of 0 °.

Next, the control unit 14 performs control so that the set temperature of the thermostatic chamber 21 becomes T (i2) (step S13). Since i2 = 2 at first, the controller 14 sets the set temperature of the thermostatic chamber 21 to +25.
Control to be at ℃. The thermostat 21 outputs the temperature in the thermostat 21 to the controller 14 to the controller 14, and the controller 14 checks whether the temperature in the thermostat 21 reaches T (i2) every other minute, for example. Thus, the process waits until the temperature in the thermostatic chamber 21 reaches T (i2) (step S14).
N, S15). When the temperature in the thermostatic chamber 21 reaches T (i2) (Y in step S14),
Aging is performed for Ag, that is, 90 minutes (the current state is maintained) (step S16).

When the measurement angle and the temperature of the thermostatic chamber 21 are determined, the control unit 14 displays the gradations of at least the sub-pixels in all the optical measurement regions as R (i3), G (i3), and B (i3) (Step S1).
7). The control unit 14 acquires the brightness measurement data of this display from the optical measuring device 17, and the acquired brightness measurement data is an array corresponding to the set temperature T (i2) and the measurement angle A (i1) of the thermostatic chamber at this time. The value is automatically stored in the storage circuit 24 as the value of the variable K (i2, i1, i3) (step S18). When this storage is completed, the control unit 14 determines that the loop variable i3 is 63 of the final gradation.
Until i3, i3 is incremented by 1 to acquire and store luminance measurement data for all gradations (steps S17 to S20).

Then, the control unit 14 increases the i until the loop variable i2 reaches the final set temperature of −20 ° C.
2 is decremented by 1 to store luminance measurement data for all gradations (steps S13 to S22). When i2 is decremented by one, the loop variable i3 is returned to zero. Further, the control unit 14 determines that the loop variable i1 is −3 of the final measurement angle.
Until it becomes 0 °, i1 is decremented by 1 and the luminance measurement data for all gradations is stored (steps S12 to S24). When decrementing i1 by 1, the loop variable i2 is returned to 2, and i3 is returned to 0.

Thus, in the optical characteristic measurement system 10 of the display device according to the present embodiment, the measurement angle of the liquid crystal display panel 12 and the environmental temperature are changed by the program, and the control unit 14 automatically sets the measurement angle of the liquid crystal display panel 12. Since the measurement data can be automatically acquired and stored by changing to a predetermined angle, the time required for measurement can be greatly shortened as compared with the conventional manual measurement method. In addition, when the optical characteristic measurement system 10 of the display device according to the present embodiment is activated, the operator automatically proceeds to the measurement operation until the measurement is completed. Therefore, the operator does not continue to monitor the optical characteristic measurement system 10 of the display device. At the same time, it becomes possible to prevent human measurement errors.

Once the standard γ characteristic is obtained, the next step is to obtain an electrical LUT. As shown in FIG.
A variable is defined (step S30). As in the flowchart of FIG. 8, the definition of the variables is the setting of red, green, and blue gradations, the setting temperature (° C) of the thermostat, the setting of the measurement angle (°), and the aging time of the thermostat Set (minutes) and define standard brightness array variables. In addition to this array variable, the luminance measured in a state including crosstalk is defined as k, the error rate before the update between the measured luminance and the standard luminance is defined as WF1, and the error rate after the update is defined as WF2. Define
The variable of the temporary correction value is defined as h, and the array variable of the correction value at the set temperature of each thermostat, the respective measurement angle, the respective gradation on the viewing angle side, and the respective gradation on the non-viewing angle side. H (0,
0, 0, 0) to H (2, 2, 63, 63).

The control unit 14 uses the standard luminance array variable K (0, 0, 0) stored in step S18 of FIG.
) To K (2, 1, 63) are read (step S31). Since the data with the measurement angle of 0 ° is reference data for verification, the standard luminance array variable K is used for obtaining the electric LUT.
(0, 2, 0) to K (2, 2, 63) need not be read. Then, the initial value of the thermostat temperature loop variable i1 is set to 2, the initial value of the measurement angle loop variable i2 is set to 1, and the initial value of the gradation loop variable i3 is set to 0 (step S32). As in the case of FIG. 8, the control unit 14 performs control so that the set temperature of the thermostatic chamber 21 becomes T (i1) (step S33).
The thermostatic chamber 21 outputs the temperature in the tank to the control unit 14 to the control unit 14, and the control unit 14 checks whether the temperature in the tank reaches T (i1) every 1 minute. Wait until the temperature reaches T (i1) (N in step S34, S35). When the temperature in the tank reaches T (i1) (Y in step S34), it is aged for Ag, that is, 90 minutes (the current state is maintained) (step S36). As in the case of FIG. 8, the control unit 14 sets the motor 25 of the rotation unit 19 to A (i2).
Control is performed so that the measurement angle becomes (step S37). Since the initial i2 is 1, the initial measurement angle is + 30 °.

Then, a crosstalk correction value acquisition process of a subroutine is performed (step S38). This subroutine will be described with reference to the flowchart of FIG. First, the control unit 14 sets the temporary correction value variable h to a negative value −5 that is far away, and 1 that is far away from the rate before updating the error from the standard luminance.
The initial value of the loop variable i3 for the viewing angle side gradation is set to 0, and the initial value of the loop variable i4 for the non-viewing angle side gradation is set to 0 (step S50). If i3 + h becomes negative in advance, i3
After changing the variable h so that + h = 0 (steps S51 and S52), the control unit 14 sets the gradations of the sub-pixels on the viewing angle side at least in all the optical measurement regions to R (i3 + h), G (i3
+ H), B (i3 + h), the gradations of the sub-pixels on the non-viewing angle side are R (i4), G (i4), B (
Displayed in i4) (step S53).

The control unit 14 acquires the brightness measurement data of this display from the optical measuring instrument 17 and sets it as a variable k (
In step S54), the error rate WF2 = abs () between the set temperature T (i1), the measurement angle A (i2), and the array function K (i1, i2, i3) of the standard luminance at the time of gradation. (K (
i1, i2, i3) -k) / K (i1, i2, i3)) are calculated (step S55).
The control unit 14 increments the gradation of the subpixel on the viewing angle side by 0.25 gradation until the error rate becomes the minimum, and the correction value when the minimum is reached is the set temperature of the constant temperature bath at that time. The measured angle, the gradation on the viewing angle side, and the gradation on the non-viewing angle side are stored in the storage circuit 24 (steps S56 to S59).

Specifically, the control unit 14 determines that the error rate WF2 calculated in step S55 is the error rate W before update.
If it is smaller than F1 (N in step S56), the error rate WF1 is updated to the error rate WF2 on the assumption that there is still a minimum error correction value, and then the temporary error rate h is added by 0.25 (step S57). . If i3 + h does not exceed the maximum 63 (N in step S58)
), The process returns to step S53. If the error rate WF2 calculated in step S55 is greater than or equal to the error rate WF1 before update (Y in step S56), the control unit 14 assumes that the correction value of the previous loop is the lowest and sets the current correction value. A value obtained by subtracting 0.25 from h is stored in the storage circuit 24 in correspondence with the set temperature, measurement angle, viewing angle side gradation, and non-viewing angle side gradation at that time, and a temporary correction value h is stored. Returning to -5, the error rate WF1 before update is returned to 1 (step S59). If i3 + h exceeds the maximum 63, the control unit 14 determines that an abnormal state has occurred and proceeds to step S59 to exit the loop.

After the processing of step S59, the control unit 14 increments i4 by 1 until the loop variable i4 indicating the non-viewing-angle side gradation reaches 63 of the final gradation, and repeats steps S53 to S59 ( Step S60 to Step S61). When the loop variable i4 reaches the final gradation 63 (Y in step S60), the control unit 14 sets i3 to 1 until the loop variable i3 indicating the viewing-angle-side gradation reaches the final gradation 63. The loop variable i4 is incremented and returned to 0, and Steps S51 to S61 are repeated (Steps S62 to S63). When the loop variable i3 reaches the final gradation 63 (Y in step S62), the control unit 14 ends the subroutine in step S38 and proceeds to step S39 in FIG.

The controller 14 decrements i2 by 1 until the loop variable i2 reaches −30 ° of the final measurement angle, and repeats Step S37 and Step S38 (Steps S39 to S38).
Step S40). Further, the control unit 14 determines that the loop variable i1 is −20, which is the final set temperature.
I1 is decremented by 1 and the loop variable i2 is set to 2, i3
Is returned to 0, and Steps S33 to S40 are repeated (Steps S41 to S42). According to the flowcharts of FIGS. 9 and 10, the inventor can measure the angles + 30 ° and −30 °.
The two types of electrical LUTs are acquired. The inventor may perform correction using different LUTs, or may calculate an intermediate value and perform correction using a common LUT.

As described above, as shown in FIG. 8, the control unit 14 performs optical measurement each time the value is changed in a triple loop of measurement angle, temperature, and gradation in order from the outside. By storing optical measurement values corresponding to the measurement angle and gradation, the standard luminance (γ characteristic) is automatically acquired.
Further, as shown in FIG. 9 and FIG. 10, the control unit 14 sets values in a five-fold loop of temperature, measurement angle, gradation on the viewing angle side, gradation on the non-viewing angle side, and provisional correction value in order from the outside. The correction value when the error rate from the standard luminance is the smallest is obtained each time the value is changed, and stored automatically corresponding to the temperature, measurement angle, gradation on the viewing angle side, and gradation on the non-viewing angle side. Obtain an electrical LUT.

As a result, the optical characteristic measurement system 10 of the display device according to the present embodiment can automatically acquire and store γ characteristics and electrical LUTs corresponding to a plurality of temperatures and measurement angles, so that conventional manual measurement is possible. Compared with the method, the time required for measurement can be greatly shortened. Further, when the optical characteristic measurement system 10 for the display device according to the present embodiment is activated, the operator automatically proceeds with the measurement operation until the measurement is completed. Therefore, the operator can use the optical characteristic measurement system 10 for the display device according to the present embodiment. It is not necessary to continue monitoring, and human measurement errors can be prevented.

The order of the multiple loops is the measurement angle, temperature, and gradation in order from the outside in the case shown in FIG. 8, and in the order shown in FIGS. 9 and 10, the temperature, measurement angle, The gradation on the viewing angle side, the gradation on the non-viewing angle side, and provisional correction values are used, and the order of the measurement angle and temperature is different. 9 and 10, in order to change the temperature outside the loop after changing the measurement angle inside the loop, the aging is performed at one measurement angle as shown in FIG. Since it does not have to be performed a plurality of times, the measurement time can be further shortened.

In the two-screen display device having the slit of the light shielding layer, as shown in FIG. 11, optical crosstalk XT2 is added in addition to electrical crosstalk XT1. Optical crosstalk XT
The cause of 2 is light leakage due to diffraction of light of the same color sub-pixel of the adjacent pixel. To this end, FIG.
6, compared with the block diagram shown in FIG. 6, an optical correction unit 42 is added to the crosstalk correction unit 35, and an optical LUT 43 is also stored in the EEPROM 32 ′ in addition to the electrical LUT 41.

When the power of the two-screen display device 30 ′ is turned on, the optical LUT 43 is written from the EEPROM 32 ′ to the optical correction unit 42, and the optical correction unit 42 subtracts the gradation of the sub-pixel to be corrected and the same color of the adjacent pixel. Optical correction data is output from the gradation of the pixel to the arithmetic unit using the optical LUT 43. The arithmetic unit 40 adds the electrical correction data and the optical correction data to the gradation of the sub-pixel to be corrected. As described above, in the two-screen display device having the slits of the light shielding layer, optical crosstalk is added in addition to electrical crosstalk, so the optical LUT 43 must also be obtained by experiment. In the case of 6-bit gradation data, the optical LUT has 64 types of gradations of sub-pixels to be corrected and 64 types of gradations of the same color sub-pixels of adjacent pixels.
The combinations are 64 × 64 = 4096 types.

Such an optical LUT 43 can also be automatically acquired and stored in the same manner as in the case of the electrical LUT 41 described above, so that the time required for measurement is greatly increased compared to the conventional manual measurement method. It can be shortened.

When the slit 28 as shown in Patent Document 3 is deviated from the center line, the viewing direction angle differs between the driver seat direction and the passenger seat direction. For example, as shown in FIG.
When deviating from the direction of the passenger seat, the angle in the driver's seat direction is smaller than the angle in the passenger seat direction,
It becomes difficult for the driver to look into the image for the passenger seat. In this way, when the slit 28 is displaced, the angle of the viewing direction is different on the left and right, so that the amount of optical crosstalk caused by diffraction is different on the left and right. For this purpose, left and right optical LUTs must be acquired. Thus, even if the optical LUT has a large number of combinations of gradations and requires optical measurement in different viewing directions, the measurer can automatically acquire the optical LUT by applying the present invention.

The application of the optical characteristic measurement system of the display device according to the above-described embodiment is γ characteristic or LU
However, the present invention is not limited to this, and can be used, for example, for flicker countermeasures by developers and sampling inspections by quality managers. In addition, the above-described optical characteristic measurement system for a display device has been applied to a two-screen liquid crystal display device having a particularly large effect. However, not only a two-screen liquid crystal display device but also a CRT, an organic EL display device, The present invention is equally applicable to a display device such as a plasma display device and a 3D display device.

DESCRIPTION OF SYMBOLS 10 ... Optical characteristic measuring system 11 ... Liquid crystal module 12 ... Liquid crystal display panel 13 ...
Backlight 14 ... Control unit 15 ... Image processing circuit 16 ... Backlight drive circuit 17
... Optical measuring instrument 18 ... 1st IF 19 ... Rotating part 20 ... 2nd IF 21 ... Constant temperature bath 22 ...
3rd IF 23 ... CPU 24 ... memory circuit 25 ... motor 26 ... color filter layer
27 ... Light shielding layer 28 ... Slit 30 ... Dual screen display device 31 ... Signal processing circuit 32 ... E
EPROM 33 ... power supply circuit 34 ... two-screen composition unit 35 ... crosstalk correction unit 3
6 ... Output signal generation unit 37 ... EEPROM controller 38 ... Pre-processing unit 39 ... Electric correction unit 40 ... Calculation unit 41 ... Electric LUT 42 ... Optical correction unit 43 ... Optical LUT 50
... Navigation device 51 ... Navigation unit 52 ... DVD playback unit XT1 ... Electric crosstalk XT2 ... Optical crosstalk

Claims (7)

An optical characteristic measurement system for a display device that displays an image,
An optical measuring instrument that outputs data measured by measuring optical characteristics of an image displayed on the display device, a rotation unit that rotates the display device to a predetermined angle corresponding to the input angle control signal, and A control unit that outputs the angle control signals corresponding to a plurality of predetermined angles to the rotating unit, and acquires and stores measurement data from the optical measuring device corresponding to the predetermined angles. An optical characteristic measuring system for a display device. The control unit outputs a plurality of image patterns having different gradations to the display device, and acquires measurement data from the optical measuring device corresponding to each measurement angle each time the gradation of the image pattern is switched. The optical characteristic measurement system for a display device according to claim 1, wherein the optical characteristic measurement system stores the optical characteristic. The display device further includes a thermostatic chamber for switching and maintaining the display device at a plurality of predetermined temperatures corresponding to the input temperature control signal, and the control unit measures the measurement data from the optical measuring instrument for each predetermined temperature. The optical characteristic measurement system for a display device according to claim 1, wherein the optical characteristic is acquired and stored in correspondence with the respective measurement angles. The control unit outputs a plurality of different gradation image patterns to the display device, and acquires and stores measurement data corresponding to each measurement angle and temperature each time the gradation of the image pattern is switched. The system for measuring optical characteristics of a display device according to claim 3. The control unit performs an optical measurement by changing a provisional crosstalk correction value to be added to a correction target gradation for each gradation of the minimum unit, and obtains a provisional crosstalk correction value for which an optical measurement result is optimum. 4. The optical characteristic measuring system for a display device according to claim 3, wherein the optical characteristic measuring system is obtained and stored in correspondence with each measurement angle and temperature. The said display apparatus has a light shielding film provided with the opening which displays a 1st image and a 2nd image so that discrimination | determination is possible in a 1st viewing direction and a 2nd viewing direction. Display device optical characteristic measurement system. 4. The display device according to claim 3, wherein the control unit switches the temperature of the thermostatic chamber after finishing measurement at all measurement angles and outputs a control signal for performing aging for a predetermined time. 5. Optical property measurement system.

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