JP2007279213A - Luminance inspecting device for display panel, and display panel manufacturing method using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a luminance inspecting device for a display panel, which corrects the luminance of a display panel highly precisely, and also to provide a display panel manufacturing method using the luminance inspecting device. <P>SOLUTION: The luminance inspecting device 1 for inspecting the luminance of the liquid crystal panel (display panel) with a plurality of pixels is provided with: a signal controller 10 which outputs a drive inspection signal to the liquid crystal panel P and makes the liquid crystal display panel P perform displaying in pixel units with a luminance value directed by the drive inspection signal; an image pickup part 3 which performs image pickup operation to every pixel of the liquid crystal panel P and acquires an image pickup data in pixel units; and correction data generating part 14 which uses the luminance value directed by the drive inspection signal and the image pickup data acquired by the image pickup part 3, to generate a correction data of a drive signal for driving the liquid crystal panel P in pixel units. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a display panel brightness inspection apparatus for inspecting the brightness of a display panel used in a liquid crystal display apparatus and the like, and a display panel manufacturing method using the same.

  In recent years, for example, liquid crystal display devices have been widely used in liquid crystal televisions, monitors, mobile phones, and the like as flat panel displays having features such as thinness and light weight compared to conventional cathode ray tubes. Such a liquid crystal display device is provided with a liquid crystal panel as a display panel, and an image such as a still image or a moving image and information including characters are displayed on the liquid crystal panel. Further, in the liquid crystal display device, for example, at the time of inspection at the factory shipment, the (front) luminance at the center position of the liquid crystal panel is measured by a luminance meter, and the luminance performance of the liquid crystal panel (liquid crystal display device) based on the measurement result Evaluation is generally performed.

Further, in a conventional display panel brightness inspection apparatus, as described in Patent Document 1 below, for example, a digital still camera (imaging unit) is used to capture a display panel displaying a predetermined image. Therefore, it is proposed to inspect the luminance of the display panel. In this conventional display panel brightness inspection apparatus, correction data for the brightness value of the display panel is acquired based on the image data of the digital still camera so that the brightness on the entire surface of the display panel is uniform. Furthermore, by using the acquired correction data, it is possible to correct the secular fluctuation of the luminance value associated with the use of the display panel in a display panel for electronic shaw kasten that requires uniform luminance over the entire display panel. It was possible.
Japanese Patent Laid-Open No. 2004-364021

  However, in the conventional display panel brightness inspection apparatus as described above, the display panel brightness cannot be inspected with high accuracy, and accurate correction data may not be obtained. For this reason, the conventional display panel brightness inspection apparatus may not be able to correct the brightness of the display panel with high accuracy.

  More specifically, in the conventional display panel luminance inspection apparatus, the display panel is divided into a plurality of regions, and the average luminance value for each divided region is acquired based on the imaging data. Furthermore, based on an empirical rule that the luminance of the central portion of the display panel is high, the ratio of luminance uniformity with respect to the central portion in each region other than the central portion is obtained in advance, and correction data for the luminance average value is obtained for each region. I was getting. As described above, in the conventional display panel brightness inspection apparatus, the brightness of the display panel is corrected using the correction data for each of the divided areas, and thus the display panel cannot be corrected with high accuracy. There was a fear.

  Further, it is also shown that the conventional display panel brightness inspection apparatus calculates correction data in pixel units using two-dimensional interpolation such as spline interpolation. However, such correction data by two-dimensional interpolation is easily influenced by the data accuracy of the interpolation source, and accurate correction data may not be obtained. In particular, it is applied to high-definition display panels for high-performance (high-definition) display devices that are required to dynamically and accurately change the luminance value of each pixel according to changes in the display image. Thus, it has been virtually impossible to create highly accurate correction data for each pixel.

  In view of the above problems, an object of the present invention is to provide a display panel brightness inspection apparatus capable of correcting the brightness of a display panel with high accuracy, and a display panel manufacturing method using the same.

In order to achieve the above object, a brightness inspection apparatus for a display panel according to the present invention is a brightness inspection apparatus for inspecting the brightness of a display panel having a plurality of pixels,
A signal control unit that outputs a driving inspection signal for inspection to the display panel and displays the display panel in a pixel unit with a luminance value instructed by the driving inspection signal;
An imaging unit that performs an imaging operation on each of the plurality of pixels of the display panel to acquire imaging data in units of pixels;
A correction data generation unit that generates correction data of a drive signal for driving the display panel on a pixel-by-pixel basis using the luminance value instructed by the drive inspection signal and the imaging data acquired by the imaging unit; It is characterized by having.

  In the luminance inspection apparatus for a display panel configured as described above, the imaging unit performs an imaging operation on all the pixels of the display panel, and acquires imaging data in units of pixels. In addition, the correction data generation unit generates correction data of the drive signal for driving the display panel using the luminance value instructed by the drive inspection signal output from the signal control unit and the imaging data acquired by the imaging unit. It is generated for each pixel. As a result, the correction data generation unit can obtain the correction data in a state where the magnitude of the deviation between the luminance value instructed by the drive inspection signal and the luminance value actually displayed on the display panel is grasped. Thus, accurate correction data for the luminance value of each pixel can be generated. As a result, the display panel brightness inspection apparatus can correct the brightness of the display panel with high accuracy.

Further, in the luminance inspection device for the display panel, the correction data generation unit is configured to input the imaging data from the imaging unit based on the luminance characteristics of the imaging unit, and to specify a luminance value indicated by the drive inspection signal. A data conversion unit for converting to a luminance value for comparison with
A correction data determination unit that determines correction data of the drive signal from the luminance value converted by the data conversion unit based on the luminance characteristics of the display panel may be provided.

  In this case, the correction data generation unit can generate correction data in units of pixels reflecting each luminance characteristic of the imaging unit and the display panel, and the correction data can be obtained more accurately.

  In the luminance inspection apparatus for the display panel, it is preferable that the signal control unit outputs the drive inspection signal corresponding to all the luminance values that can be displayed on the display panel to the display panel.

  In this case, the correction data generation unit can generate accurate correction data for all the brightness values in all the pixels of the display panel, and correct the display panel brightness with higher accuracy. Can do.

In the display panel brightness inspection apparatus, the imaging unit includes a plurality of imaging elements,
The plurality of imaging elements may perform an imaging operation on a plurality of imaging regions set different from each other on the plurality of pixels of the display panel.

  In this case, since a plurality of imaging data is acquired by the imaging unit in each pixel described above, it is possible to improve the inspection accuracy of the luminance value of each pixel. As a result, the correction data generation unit can easily generate accurate correction data, and the luminance of each pixel of the display panel can be corrected with higher accuracy.

  The display panel brightness inspection apparatus preferably further includes a data output unit for writing correction data of the drive signal generated by the correction data generation unit to a storage unit provided in the display panel.

  In this case, since the data output unit writes and stores the correction data from the correction data generation unit in the storage unit on the display panel side, the correction data can be reliably and easily reflected in the display operation on the display panel. The performance of the display panel can be easily improved.

Moreover, the manufacturing method of the display panel of the present invention is a manufacturing method including an inspection process for inspecting the luminance of the display panel,
The inspection step is performed using any one of the above luminance inspection apparatuses.

  In the display panel manufacturing method configured as described above, accurate correction data for the luminance values of all the pixels of the display panel is acquired in the display panel inspection process. Therefore, the brightness of the display panel can be corrected with high accuracy, and a display panel having excellent display performance can be easily manufactured.

  ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to provide the brightness | luminance inspection apparatus of the display panel which can correct | amend the brightness | luminance of a display panel with high precision, and the manufacturing method of a display panel using the same.

  Hereinafter, a preferred embodiment of a display panel brightness inspection apparatus and a display panel manufacturing method using the same according to the present invention will be described with reference to the drawings. In the following description, a case where the present invention is applied to a liquid crystal display device including a transmissive liquid crystal panel will be described as an example.

  FIG. 1 is a block diagram illustrating a main part of a luminance inspection apparatus for a display panel according to an embodiment of the present invention. In FIG. 1, the luminance inspection apparatus 1 of the present embodiment includes a control device 2 and an imaging unit 3 that performs an imaging operation on a liquid crystal panel P as a display panel to be inspected. The brightness of each of a plurality of pixels included in the liquid crystal panel P is inspected using the imaging result. Further, the luminance inspection apparatus 1 is provided on the display surface side of the liquid crystal panel P, and is provided on the non-display surface side of the liquid crystal panel P, and the illumination unit 4 that illuminates the imaging location of the imaging unit 3 on the display surface. A test backlight 5 that emits predetermined illumination light according to the liquid crystal panel P, and a position changing unit 6 that is connected to the imaging unit 3 and changes its imaging location are provided.

  Furthermore, in the brightness inspection apparatus 1, the display unit 7 is connected to the control device 2, and the imaging result of the imaging unit 3 is displayed on the display unit 7. Further, in the luminance inspection apparatus 1, for example, an operation instruction from an operator can be input using a touch panel function given to the display unit 7. That is, in the brightness inspection apparatus 1, an operator instruction such as start or stop of an inspection process for inspecting the brightness of the liquid crystal panel P is input by the touch panel function, and the manufacturing process of the liquid crystal panel P is performed according to the input instruction. The above-described inspection process included in is performed. Further, in the luminance inspection apparatus 1, as illustrated in FIG. 1, the temperature sensor 8 is connected to the control device 2, and the control device 2 uses the detection data of the ambient temperature from the temperature sensor 8, thereby performing the inspection process. It is possible to prevent as much as possible the influence of ambient temperature fluctuations from appearing in the inspection results.

  A microcomputer is used for the control device 2, and the control device 2 is configured to perform drive control of each part of the luminance inspection device 1. The control device 2 is configured to be connectable to the liquid crystal panel P, and can perform inspection while performing drive control of the liquid crystal panel P. That is, as will be described in detail later, the control device 2 outputs a drive inspection signal to the liquid crystal panel P to perform a luminance inspection in a state where a predetermined image for inspection is displayed, and further to the inspection result. Based on this, correction data can be created for each pixel.

  Moreover, the control apparatus 2 is comprised so that connection to the data communication network (not shown) of the management system installed, for example in the manufacturing factory is possible. The control device 2 can perform bidirectional data communication with an external data processing device such as an external storage device M incorporated in the system server on the network or the liquid crystal panel P. Furthermore, when the control device 2 obtains predetermined panel information about the liquid crystal panel P such as design information and manufacturing information in advance from the system server, for example, the luminance inspection device 1 performs high-precision inspection of the liquid crystal panel P. It is configured to be easily implemented.

  Specifically, the control device 2 includes an imaging control unit 9, a signal control unit 10, a backlight control unit 11, an illumination control unit 12, and a position control unit 13 that are functionally provided in a CPU or MPU of a microcomputer. A correction data generation unit 14 and a data input / output unit 15. Further, the control device 2 is provided with a data storage unit 16 configured using a memory of a microcomputer or the like, and various programs for causing each unit of the control device 2 to function are held in the data storage unit 16. Yes. Further, the data storage unit 16 appropriately stores data from each part of the luminance inspection apparatus 1 such as the imaging result and external data such as the panel information.

  The imaging unit 3 is configured to perform an imaging operation in accordance with an instruction signal from the imaging control unit 9, and performs an imaging operation on all of the plurality of pixels of the liquid crystal panel P to obtain imaging data in units of pixels. To get. In addition, for the imaging unit 3, for example, a two-dimensional sensor in which CCDs (Charge Coupled Devices) as a plurality of imaging elements are arranged in a planar shape is used. Specifically, in the imaging unit 3, for example, 2688 pieces in the vertical direction and 4032 pieces in the horizontal direction, a total of about 11 million CCDs are arranged, and the liquid crystal panel P is imaged in plan by these CCDs. Then, the luminance value is acquired for each CCD.

  In the imaging unit 3, as illustrated in FIG. 2, a plurality of, for example, 12 CCDs are assigned to each of RGB pixels provided on the liquid crystal panel P. That is, in the imaging unit 3, as shown in FIG. 2, twelve different imaging regions 31 are set on one R pixel. In the imaging unit 3, the CCD corresponding to each of the twelve imaging regions 31 performs an imaging operation, whereby twelve luminance value imaging data kd1 to kd12 in one R pixel are transmitted from the imaging unit 3 to the control device. 2 is output.

  Further, in the imaging unit 3, the CCD imaging operation is appropriately performed according to the panel configuration such as the size of the liquid crystal panel P and the number of pixels. That is, as described above, the imaging unit 3 is connected to the position changing unit 6, and the position changing unit 6 operates according to the instruction signal from the position control unit 13 of the control device 2, so that the panel of the liquid crystal panel P is operated. Depending on the configuration, the imaging location on the display surface of the liquid crystal panel P is appropriately changed. Thereby, in the imaging part 3, the imaging operation with respect to all the pixels is performed, and the imaging result of each luminance value is obtained, without imaging omission.

  Specifically, the position changing unit 6 includes a support unit that is connected to the imaging unit 3 and supports the imaging unit 3 above the liquid crystal panel P, and a moving unit that moves the support unit. In the position changing unit 6, the moving unit moves the support unit based on an instruction signal from the position control unit 13, so that the imaging unit 3 can be moved three-dimensionally with respect to the liquid crystal panel P. Thus, since the imaging unit 3 is moved three-dimensionally by the instruction signal from the control device 2 with the position changing unit 6 interposed, the liquid crystal panel P is a panel corresponding to, for example, VGA (Video Graphics Array). Even in this case, the position changing unit 6 sequentially moves the imaging unit 3 in the direction parallel to the display surface of the liquid crystal panel P, that is, the horizontal direction and the vertical direction of the display surface, so that the imaging unit 3 is included in the liquid crystal panel P. Appropriate imaging operations for the 921600 (= 480 × 640 × 3) pixels can be sequentially performed. In addition, the position changing unit 6 moves the imaging unit 3 in a direction perpendicular to the display surface of the liquid crystal panel P, thereby changing the distance between the imaging unit 3 and the display surface, so that the focal length ( (Focus) can be changed appropriately.

  The illumination unit 4 is provided with a light source that performs a lighting operation based on an instruction signal from the illumination control unit 12 of the control device 2, and the imaging location of the imaging unit 3 is set to a predetermined brightness by reflected light from the light source. The imaging operation is performed in a state illuminated under the conditions.

  A linear light source such as a cold cathode tube or a point light source such as an LED is used for the inspection backlight 5, and the inspection backlight 5 is in accordance with an instruction signal from the backlight control unit 11 of the control device 2. Lights up and irradiates illumination light from the back of the liquid crystal panel P. Further, backlight information related to a product backlight that is assembled into the liquid crystal panel P and integrated as a liquid crystal display device is acquired in advance from the system server, for example. The backlight control unit 11 generates the instruction signal based on the backlight information and outputs the instruction signal to the inspection backlight 5. As a result, the luminance inspection apparatus 1 can easily perform the luminance inspection when the amount of light from the backlight included in the liquid crystal display device is changed, that is, when the dimming range of the backlight of the actual product is changed. Can be implemented.

  The signal control unit 10 outputs the above-described driving inspection signal for inspection to the liquid crystal panel P, and causes the liquid crystal panel P to be displayed pixel by pixel with a luminance value indicated by the driving inspection signal. More specifically, the drive inspection signal includes an instruction signal output to the gate and source of each of a plurality of TFTs (Thin Film Transistors) as active elements provided in the liquid crystal panel P for each pixel. That is, the drive inspection signal is output to the gate of each TFT, and is output to the gate pulse signal for turning the gate on or off, and to the source of each TFT. A voltage signal corresponding to an image (video) signal for displaying a predetermined image for inspection is included. Then, the signal control unit 10 drives the liquid crystal panel P pixel by pixel with the gate turned on by the gate pulse signal. Further, the signal control unit 10 determines a voltage signal to be supplied to the source by determining a voltage signal to the source (hereinafter referred to as “source voltage”), and applies the above-described test signal to the corresponding pixel. The brightness value in the predetermined image is indicated.

  The signal control unit 10 is configured to be able to output to the liquid crystal panel P drive test signals corresponding to all the luminance values that can be displayed by the pixels of the liquid crystal panel P. That is, the signal control unit 10 changes the voltage signal (drive inspection signal) so that the source voltage is increased or decreased, thereby displaying the inspection image at all the luminance values in each pixel. In other words, in each pixel, the luminance value is different from each other in accordance with the increase or decrease of the source voltage, and the inspection image is displayed at all the gradation values defined by the value of the source voltage.

  The correction data generation unit 14 is provided with a data conversion unit 14a and a correction data determination unit 14b. The luminance value instructed by the drive inspection signal from the signal control unit 10 to the liquid crystal panel P and the imaging unit 3 are provided. The correction data of the drive signal for driving the liquid crystal panel P is generated on a pixel basis using the imaging data acquired in (1). That is, in the correction data generation unit 14, as will be described in detail later, the data conversion unit 14 a converts the imaging data from the imaging unit 3 based on the luminance characteristics of the imaging unit 3 to the luminance value indicated by the drive inspection signal. Are converted into luminance values for comparison. Further, the correction data determination unit 14b determines the correction data of the drive signal from the luminance value converted by the data conversion unit 14a based on the luminance characteristics of the liquid crystal panel P. Thereby, in the brightness inspection apparatus 1, correction data for each pixel is generated from the imaging result of the imaging unit 3 according to each brightness value, and can be reflected in the image display of the liquid crystal panel P.

  The data input / output unit 15 has an interface function, and exchanges data between the control device 2 and an external device such as a system server on the data communication network. Further, the data input / output unit 15 constitutes a data output unit that writes correction data of the drive signal generated by the correction data generation unit 14 to the external storage device M as a storage unit on the liquid crystal panel P side. . Thus, in the brightness inspection apparatus 1, the data input / output unit 15 outputs and holds the correction data to the external storage device M, so that the correction data is reliably and easily reflected in the display operation on the liquid crystal panel P. Can be made. Therefore, the performance of the liquid crystal panel P can be easily improved.

  In addition to the above description, a data input device such as a keyboard or a pointing device is connected to the data input / output unit 15 to input data (information) such as operation instructions to the control device 2 and the luminance inspection device 1. May be.

  Hereinafter, the operation of the luminance inspection apparatus 1 of the present embodiment configured as described above will be specifically described with reference to FIGS. In the following description, for the sake of simplification of explanation, a case where the luminance inspection is performed with the amount of illumination light from the inspection backlight 5 to the liquid crystal panel P being constant will be described as an example.

  As shown in step S <b> 1 of FIG. 3, first, in the luminance inspection apparatus 1 of the present embodiment, when the start of the inspection process is instructed by an operator, the activation process is performed by the control device 2. In this activation process, instruction signals for the respective units of the luminance inspection apparatus 1 are determined by the corresponding control units of the control apparatus 2 so that the luminance inspection for the liquid crystal panel P is appropriately performed.

  Specifically, in the start-up process, in addition to predetermined information about each part of the luminance inspection apparatus 1 such as lens characteristics and light receiving sensitivity characteristics relating to the CCD of the imaging unit 3 stored in advance in the data storage unit 16, liquid crystal An instruction signal is determined based on information such as the panel information of the panel P. In other words, in the start-up process, the number of times of imaging of the imaging unit 3 and the imaging timing, the moving method (distance, direction, etc.) of the imaging unit 3 by the position changing unit 6, the light emission (illumination) intensity of the illumination unit 4, and the like Is appropriately determined according to the condition and included in the instruction signal. In the signal control unit 10, a drive inspection signal for displaying an inspection image with all controllable gradation values is generated in the liquid crystal panel P and is output to the liquid crystal panel P.

  In the start-up process, the correction data generation unit 14 determines a correction coefficient for correcting the temperature variation in the output from the CCD based on the measurement data of the ambient temperature detected by the temperature sensor 8, and the imaging unit 3. An arithmetic process is performed to prevent a reduction in accuracy due to temperature fluctuations in the imaging result. In addition to this explanation, other sensors such as a humidity sensor are provided to eliminate the influence of disturbance such as the influence of the environment around the luminance inspection apparatus 1 and the passage of time (deterioration over time), thereby enhancing the inspection process. It can also be done with precision.

  Next, in the luminance inspection apparatus 1, as shown in step S <b> 2 of FIG. 3, the position changing unit 6 operates based on the instruction signal from the position control unit 13, and the alignment process for the liquid crystal panel P of the imaging unit 3. Is implemented. That is, in this alignment process, for example, by displaying the captured image from the imaging unit 3 on the display unit 7 in an enlarged manner, the imaging start position of the liquid crystal panel P of the imaging unit 3 predetermined in the activation process (for example, the upper left corner) ) Is confirmed by the operator. Thereby, as illustrated in FIG. 2, a plurality of CCDs of the imaging unit 3 are allocated to one pixel of the liquid crystal panel P, and each CCD can perform an imaging operation.

  Subsequently, in the luminance inspection apparatus 1, as illustrated in step S3 of FIG. 3, the imaging process of the imaging unit 3 is performed. That is, the imaging unit 3 performs an imaging operation on the liquid crystal panel P displaying the predetermined inspection image in accordance with the instruction signal from the imaging control unit 9, and the image data of the luminance value in units of pixels is stored in the data storage unit. 16 to memorize.

  Next, in the luminance inspection apparatus 1, as shown in step S <b> 4 in FIG. 3, it is determined whether or not drive inspection signals corresponding to all the gradation values are output from the signal control unit 10 to the liquid crystal panel P. If drive inspection signals corresponding to all the gradation values are not output, the process returns to step S3.

  On the other hand, when it is determined in step S4 that the drive inspection signal corresponding to all the gradation values is output from the signal control unit 10 to the liquid crystal panel P, the luminance inspection apparatus 1 performs the process as shown in step S5. Then, it is determined whether or not the imaging operation for all the pixels of the liquid crystal panel P has been completed. If the imaging operation for all the pixels has not been completed, the process returns to step S3.

  On the other hand, if it is determined in step S5 that the imaging operation for all the pixels has been completed, the luminance inspection apparatus 1 generates correction data for the luminance value of each pixel as shown in step S6. Is implemented. That is, in the correction data generation unit 14, the data conversion unit 14a is instructed by the drive inspection signal of the imaging data from the imaging unit 3 based on the luminance characteristics of the imaging unit 3 illustrated by the curve 70 in FIG. Is converted into a luminance value for comparison with the obtained luminance value. Specifically, the data conversion unit 14 a refers to the data storage unit 16, acquires the luminance value imaging data Kd for one pixel, and applies the acquired imaging data Kd to the curve 70. Thus, the luminance value 55 for comparison with the luminance value instructed by the drive inspection signal is obtained. The imaging data Kd is an average value of the twelve imaging data kd1 to kd12 illustrated in FIG. 2, and the data conversion unit 14a is held in the data storage unit 16 according to the imaging operation of the imaging unit 3. It is calculated from the imaging data kd1 to kd12.

  Next, the correction data determination unit 14b calculates the drive signal of the liquid crystal panel P from the luminance value converted by the data conversion unit 14a based on the luminance characteristic of the liquid crystal panel P exemplified by the curve 80 in FIG. Determine the correction data. Specifically, when the luminance value 55 corresponding to the imaging result of the imaging unit 3 is notified from the data conversion unit 14a, the correction data determination unit 14b applies the luminance value 55 to the curve 80, thereby A source voltage of 5.1 V (gradation value) corresponding to the luminance value 55 is obtained.

  On the other hand, the correction data determination unit 14b receives a drive inspection signal for instructing the source voltage to 5.0 V (gradation value) so that the luminance value on the pixel of the liquid crystal panel P is 50 from the signal control unit 10. The correction data determination unit 14b determines the magnitude of the deviation between the luminance value 50 instructed by the drive inspection signal and the luminance value 55 actually displayed on the liquid crystal panel P. Then, luminance value correction data is determined in consideration of the determined magnitude of deviation. That is, in the correction data generation unit 14, when the liquid crystal panel P is driven with a source voltage of 5.0 V, the pixel corresponding to the luminance value 55 when driven with a source voltage of 5.1 V higher than the source voltage. Is determined to perform the display operation. As a result, the correction data determination unit 14 recognizes that the pixel needs to be operated with a source voltage lower than 5.0 V in order to display the luminance value 50, and displays the luminance value 50. Correction data for this is determined and stored in the data storage unit 16. As described above, in the luminance inspection apparatus 1, correction data for each pixel is generated from the imaging result of the imaging unit 3 according to each luminance value, and can be reflected in the image display of the liquid crystal panel P. Note that the luminance characteristics indicated by the curve 70 and the curve 81 are input and held in advance, for example, in the data storage unit 16.

  Subsequently, in the luminance inspection apparatus 1, as shown in step S7, the data input / output unit 15 writes the correction data stored in the data storage unit 16 in step S6 into the external storage device M and stores it. Thereby, the result of the inspection process can be easily reflected in the display operation of the liquid crystal panel P.

  As described above, in the luminance inspection apparatus 1 according to the present embodiment, the signal control unit 10 outputs the drive inspection signal to the liquid crystal panel (display panel) P to be inspected, and the luminance value indicated by the drive inspection signal. Thus, each pixel of the liquid crystal panel P is displayed, and the imaging unit 3 performs an imaging operation on all the pixels of the liquid crystal panel P to acquire imaging data in units of pixels. Further, the correction data generation unit 14 uses the luminance value instructed by the drive inspection signal and the imaging data acquired by the imaging unit 3 to convert the correction data of the driving signal for driving the liquid crystal panel P in pixel units. Has been generated. As a result, the correction data generation unit 14 can grasp the magnitude of the deviation between the luminance value instructed by the drive inspection signal and the luminance value actually displayed on the liquid crystal panel P, and the magnitude of the deviation. In a state where the above is grasped, accurate correction data for the luminance value of each pixel can be generated. Therefore, unlike the above-described conventional example, the brightness inspection apparatus 1 according to the present embodiment can perform a brightness test with high accuracy in units of pixels and can correct the brightness of the liquid crystal panel P with high precision. In addition, since the luminance of the liquid crystal panel P can be corrected with high accuracy in this way, the liquid crystal panel P having excellent display performance can be easily manufactured.

  In the present embodiment, the data conversion unit 14a and the correction data determination unit 14b of the correction data generation unit 14 have the luminance characteristics of the imaging unit 3 and the luminance characteristics of the liquid crystal panel P illustrated in FIGS. 4A and 4B, respectively. Therefore, the correction data generation unit 14 can generate correction data for each pixel reflecting the above luminance characteristics, obtain more accurate correction data, and improve the display performance of the liquid crystal panel P. It can be improved easily.

  In the present embodiment, since the signal control unit 10 outputs drive inspection signals corresponding to all luminance values in the liquid crystal panel P, the correction data generation unit 14 performs all the above-described operations on all the pixels of the liquid crystal panel P. It is possible to generate accurate correction data for each luminance value. As a result, the luminance of the liquid crystal panel P can be corrected with higher accuracy, and the liquid crystal panel P having excellent display performance can be manufactured more easily.

  The above embodiments are all illustrative and not restrictive. The technical scope of the present invention is defined by the claims, and all modifications within the scope equivalent to the configurations described therein are also included in the technical scope of the present invention.

  For example, in the above description, the case where the present invention is applied to a liquid crystal display device including a transmissive liquid crystal panel has been described. However, the present invention provides luminance in units of pixels with respect to a display panel including a plurality of pixels. Any type of liquid crystal panel such as a reflection type or a transflective type, a display panel of another type such as PDP or CRT, or various display panels using a plurality of LEDs as pixels (display dots) may be used. The present invention can be applied.

  In the above description, the case of inspecting by illuminating the illumination light from the backlight for inspection from the back of the liquid crystal panel to be inspected has been described, but the present invention is not limited to this, An inspection process for luminance inspection of a liquid crystal panel (liquid crystal display device) can also be performed by using a backlight which is shipped as a liquid crystal display device by being assembled integrally with the liquid crystal panel.

  In the above description, the case where an imaging unit using a two-dimensional sensor in which a plurality of CCDs are arranged in a plane is described. However, the imaging unit of the present invention is not limited to this, and a plurality of imaging units are not limited to this. It may include a line sensor in which CCDs are arranged in a straight line and other imaging elements.

  However, as in the above-described embodiment, a plurality of different imaging areas are set on each pixel of the display panel, and an imaging operation is performed on the plurality of imaging areas using a plurality of imaging elements included in the imaging unit. In each case, a plurality of imaging (inspection) data can be acquired in each pixel, and the inspection accuracy of the luminance value of the pixel can be improved. As a result, it is possible to easily generate accurate pixel-by-pixel correction data, which is preferable in that the luminance of each pixel of the display panel can be corrected with higher accuracy, and highly accurate gradation control for display dots. Is preferable in that it can be implemented more easily.

  In addition to the above description, for example, a display panel to be inspected can be transported by a transport machine such as a transport belt to perform a brightness test on the display panel. That is, the inspection process can be performed by the control device processing the moving image data from the imaging unit in a state where the imaging unit and the display panel are relatively moved using the transport machine.

  In the above description, the case where the inspection process for inspecting the luminance of the pixel unit of the display panel is performed has been described. However, the present invention is not limited to this, and other defect detection of the pixel unit in the display panel is performed. Can also be performed.

  Specifically, in the present invention, as shown in the above-described embodiment, the control device outputs a driving inspection signal to perform a display operation in units of pixels, so that it is provided in each pixel of a liquid crystal panel, for example. It is also possible to detect the occurrence of TFT failure by determining the presence or absence of TFT malfunction. In addition, for example, by using software, a processing unit that performs spectrum (frequency) analysis processing on the imaging result of the imaging unit is functionally installed in the control device, so that each color of RGB provided on the display panel It is also possible to determine the presence or absence of defects such as abnormal formation of filters and RGB phosphors. In addition, since a plurality of image sensors are assigned to each RGB pixel, it is possible to easily perform a high-precision inspection capable of detecting a partial defect in each pixel.

It is a block diagram explaining the principal part of the brightness | luminance inspection apparatus of the display panel concerning one Embodiment of this invention. It is a figure explaining the imaging operation of the imaging part shown in FIG. It is a flowchart which shows the operation example of the said brightness | luminance inspection apparatus. (A) is a graph which shows an example of the concrete brightness | luminance characteristic of the said imaging part, (b) is a graph which shows an example of the concrete brightness | luminance characteristic of the display panel shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Brightness inspection apparatus 3 Imaging part 31 Imaging area 10 Signal control part 14 Correction data generation part 14a Data conversion part 14b Correction data determination part 15 Data input / output part (data output part)
P Liquid crystal panel (display panel)
R, G, B Pixel M External storage device (storage part of display panel)

Claims (6)

A brightness inspection apparatus for inspecting the brightness of a display panel having a plurality of pixels,
A signal control unit that outputs a driving inspection signal for inspection to the display panel and displays the display panel in a pixel unit with a luminance value instructed by the driving inspection signal;
An imaging unit that performs an imaging operation on each of the plurality of pixels of the display panel to acquire imaging data in units of pixels;
A correction data generation unit that generates correction data of a drive signal for driving the display panel on a pixel-by-pixel basis using the luminance value instructed by the drive inspection signal and the imaging data acquired by the imaging unit; A luminance inspection apparatus for a display panel, comprising: Based on the luminance characteristics of the imaging unit, the correction data generation unit converts the imaging data from the imaging unit into a luminance value for comparison with the luminance value instructed by the drive inspection signal. A data converter to
2. The display panel according to claim 1, further comprising: a correction data determination unit that determines correction data of the drive signal from the luminance value converted by the data conversion unit based on luminance characteristics of the display panel. Luminance inspection device. The display panel luminance inspection apparatus according to claim 1, wherein the signal control unit outputs to the display panel the drive inspection signal corresponding to all luminance values that can be displayed by the display panel. The imaging unit is provided with a plurality of imaging elements,
The plurality of imaging elements respectively perform an imaging operation on a plurality of imaging regions set differently from each other on the plurality of pixels of the display panel. The brightness | luminance inspection apparatus of the display panel of description. The display panel according to claim 1, further comprising a data output unit that writes correction data of the drive signal generated by the correction data generation unit to a storage unit provided in the display panel. Brightness inspection equipment. A manufacturing method including an inspection process for inspecting luminance of a display panel,
The manufacturing method of the display panel characterized by performing the said test process using the brightness | luminance inspection apparatus of any one of Claims 1-5.

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