JP2016085344A - Display device, image processor, and method for controlling the display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve display quality by more surely suppressing display unevenness in a display panel.SOLUTION: A display device includes a liquid crystal panel 112A for displaying an image on the basis of image data, and a liquid crystal driver 114 for dividing the liquid crystal panel 112A into a plurality of channels to drive the liquid crystal panels. The display device includes a correction amount LUT storage part 165 for storing a correction amount LUT corresponding to each of the channels and a point set in a horizontal direction of the liquid crystal panel 112A. Further, the display device includes a correction part 167 for correcting image data displayed at a point on the basis of the correction amount LUT to input the corrected image data in the liquid crystal panel 112, and correcting image data displayed at a position other than the point on the basis of a correction amount LUT acquired from the correction amount LUT by an interpolation calculation to input the corrected image data in the liquid crystal panel 112A.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a display device, an image processing device, and a display device control method.

  2. Description of the Related Art Conventionally, there has been known an apparatus that displays a video and an image by driving a display panel by dividing it into a plurality of channels (for example, see Patent Document 1). In this type of device, it has been pointed out that display unevenness occurs when there is a difference in the output level of signals output to the respective channels. For this reason, a method for correcting the output level of the signal has been proposed. For example, the device described in Patent Document 1 corrects an image signal output to each channel by using a plurality of reference signals when the pixel of the display panel is driven by being divided into a plurality of channels in the horizontal direction. This prevents display unevenness.

JP 2010-122577 A

By the way, a display panel such as a liquid crystal display panel has a difference in display characteristics depending on the position in the plane, and display unevenness may occur due to the difference in display characteristics. Such display unevenness cannot be dealt with by correcting the signal for each channel described above. For this reason, even if display unevenness due to a difference in signal level for each channel is suppressed, display unevenness due to other causes may occur.
The present invention has been made in view of the above-described circumstances, and an object thereof is to more reliably suppress display unevenness in a display panel and improve display quality.

In order to achieve the above object, a display device according to the present invention includes a display panel that displays an image, a drive unit that divides and drives the display panel into a plurality of channels, each of the channels, and the display panel. A correction data storage unit that stores correction data corresponding to the representative position set in the horizontal direction, and the image data displayed at the representative position is corrected based on the correction data and input to the display panel; A correction unit that corrects image data displayed at a position other than the representative position based on interpolation correction data obtained from the correction data by interpolation, and inputs the correction data to the display panel. .
According to the present invention, the display device uses the correction data corresponding to the representative position of the display panel to reduce both the display unevenness between the channels of the display panel and the display unevenness in the horizontal direction of the display panel. Corresponding corrections can be made. Thereby, display unevenness can be more reliably suppressed and display quality can be improved.

In the display device according to the aspect of the invention, the driving unit outputs and drives a voltage to a display element of the display panel, performs polarity inversion to invert the polarity of the output voltage, and the correction data storage unit Storing the correction data corresponding to each of the channels, the representative position set in the horizontal direction of the display panel, and the polarity of the output voltage of the drive unit, and the correction unit The correction is performed with the correction data corresponding to the polarity of the output voltage of the driving unit when displaying data.
According to the present invention, when the display panel is driven by the polarity inversion method, the image data can be corrected in accordance with the polarity. Thereby, display unevenness can be more reliably suppressed and display quality can be improved.

In the display device according to the present invention, the correction data is a lookup table for converting image data, and the correction data storage unit stores the lookup table.
According to the present invention, since correction data in the form of a lookup table or data obtained by performing interpolation operation on this correction data is used, the processing load for correcting image data can be reduced.

The present invention is characterized in that, in the display device, the correction data stored in the correction data storage unit can be written by an external device.
According to the present invention, the correction data can be written by an external device. For example, the correction data can be updated as necessary.

According to the present invention, in the display device, the display panel includes a plurality of display elements arranged in a matrix, and the correction unit corrects image data displayed on each of the display elements to thereby display the display panel. Inputting.
According to the present invention, a configuration in which a plurality of display elements arranged in a matrix are divided into a plurality of channels and driven, and both display unevenness between channels of the display panel and display unevenness in the horizontal direction of the display panel are supported. Thus, the image data can be corrected.

In order to achieve the above object, the present invention is an image processing apparatus for processing image data displayed on a display panel, wherein each of the channels into which the display panel is divided is arranged in a horizontal direction of the display panel. A correction data storage unit that stores correction data corresponding to the set representative position, and image data displayed at the representative position is corrected based on the correction data and input to the display panel. And a correction unit that corrects image data displayed at a position other than that based on interpolation correction data obtained from the correction data by interpolation calculation, and inputs the correction data to the display panel.
According to the present invention, the image processing apparatus uses the data corresponding to the representative position of the display panel to reduce both the display unevenness between the channels of the display panel and the display unevenness in the horizontal direction of the display panel. Corresponding corrections can be made. Thereby, display unevenness of the display panel can be more reliably suppressed and display quality can be improved.

In order to achieve the above object, the present invention provides a method for controlling a display device including a display panel, wherein each of the channels into which the display panel is divided and a representative position set in the horizontal direction of the display panel Correction data corresponding to the image data is stored, the image data displayed at the representative position is corrected based on the correction data, input to the display panel, and the image data displayed at a position other than the representative position is stored. Correction based on interpolation correction data obtained by interpolation calculation from the correction data, input to the display panel, and driving the display panel divided into a plurality of channels based on the corrected image data. And
According to the present invention, the display device uses the data corresponding to the representative position of the display panel to cope with both display unevenness between the channels of the display panel and display unevenness in the horizontal direction of the display panel for the image data. Correction can be performed. Thereby, display unevenness of the display panel can be more reliably suppressed and display quality can be improved.

1 is a block diagram of a projector according to an embodiment. The block diagram which shows the structure of a correction | amendment part. The block diagram of a liquid crystal panel and a liquid crystal driver. The schematic diagram which shows the structure of the correction amount LUT memory | storage part. The flowchart which shows operation | movement of a projector.

Hereinafter, embodiments to which the present invention is applied will be described with reference to the drawings.
FIG. 1 is a block diagram of a projector 100 according to the embodiment.
The projector 100 (display device) is connected to an external image supply device 2 such as a personal computer or various video players, and projects an image on the screen SC based on image data input from the image supply device 2. The image supply device 2 is, for example, a video playback device, a DVD (Digital Versatile Disk) playback device, a TV tuner device, a CATV (Cable television) set top box, a video output device such as a video game device, a personal computer, or the like. The screen SC is a flat surface such as a hanging or rising curtain screen or a wall surface.

The projector 100 includes an image input unit 124 connected to the image supply device 2. The image input unit 124 is an interface that connects to the image supply device 2 by wire or wirelessly. The image input unit 124 is, for example, a DVI interface, a USB interface, or a LAN interface to which a digital video signal is input. Further, the image input unit 124 includes, for example, an S video terminal to which a composite video signal such as NTSC, PAL, or SECAM is input, an RCA terminal to which a composite video signal is input, a D terminal to which a component video signal is input, or the like. May be. Further, the image input unit 124 may include a general-purpose interface such as an HDMI connector conforming to the HDMI (registered trademark) standard.
The image input unit 124 may include an A / D conversion circuit that converts an analog video signal into digital image data. In this case, the image input unit 124 can be connected to the image supply device 2 through an analog video terminal such as a VGA terminal. The image input unit 124 receives digital image data input from the image supply device 2 and outputs the digital image data to the image processing unit 125.

The projector 100 includes a projection unit 110 that performs optical image formation roughly and an image processing system that electrically processes an image displayed by the projection unit 110.
The projection unit 110 includes a light source unit 111, a light modulation device 112, and a projection optical system 113.
The light source unit 111 includes a light source including a xenon lamp, an ultrahigh pressure mercury lamp, an LED (Light Emitting Diode), and the like. The light source unit 111 may include a reflector and an auxiliary reflector that guide light emitted from the light source to the light modulation device 112. The light source unit 111 may include any of a lens group (not shown) for enhancing the optical characteristics of the projection light, a polarizing plate, and a light control element that dimmes light emitted from the light source.

  A light source driving unit 122 is connected to the light source unit 111. The light source driving unit 122 is controlled by the control unit 130 and supplies power of a predetermined voltage to the light source unit 111 to control lighting and extinguishing of the light source. The light source driving unit 122 may output a pulse current to the light source unit 111 to control the luminance of the light source by PWM (Pulse Width Modulation).

  The light modulation device 112 modulates the light emitted from the light source unit 111 based on the image data. The light modulation device 112 includes a liquid crystal panel 112A in which a plurality of pixels (display elements) are arranged in a matrix, forms an image with the pixels of the liquid crystal panel 112A, and modulates light emitted from the light source unit 111 by the image. The liquid crystal panel 112A is a reflective or transmissive liquid crystal display panel. The light modulation device 112 may include an optical component that guides light emitted from the light source unit 111 to the liquid crystal panel 112A. The configurations of the light modulation device 112 and the liquid crystal panel 112A will be described later.

  The projection optical system 113 includes a zoom lens that performs enlargement / reduction of a projected image and a focus adjustment, a focus adjustment mechanism that performs focus adjustment, and the like. The projection optical system 113 projects the image light modulated by the light modulation device 112 onto the screen SC, and the image light is imaged on the screen SC.

  The image processing system of the projector 100 includes a control unit 130 that controls the projector 100 and other processing units. The image processing system includes a storage unit 151, an image processing unit 125, a frame memory 126, an input processing unit 153, and a correction processing unit 160 (image processing apparatus).

The control unit 130 includes a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and the like (not shown). The control unit 130 controls the projector 100 by executing a basic control program stored in the ROM and a control program stored in the storage unit 151 by the CPU.
The control unit 130 controls the light source driving unit 122 and the image processing unit 125 to project an image on the screen SC based on the image data output from the image supply device 2.

The image processing unit 125 executes image processing including any one of resolution conversion processing, trapezoidal distortion correction processing, color mode adjustment processing, and the like of image data input to the image input unit 124 or other processing. The resolution conversion process is a process for converting the resolution of the image data in accordance with the specifications of the liquid crystal panel 112A. The trapezoidal distortion correction process is a process of deforming the image so as to compensate for the trapezoidal distortion of the image formed on the screen SC. The color mode adjustment process is a process for changing the color tone or the like of the image data.
The image processing unit 125 draws an image of one frame on the frame memory 126 based on the image data, performs processing on the image in the frame memory 126, reads out the processed image data from the frame memory 126, and outputs it. . The control unit 130 specifies the type of processing executed by the image processing unit 125 and the parameters used in the processing.

  The storage unit 151 is a non-volatile storage unit having a flash memory, an EEPROM, or the like. The storage unit 151 stores data processed by the control unit 130 and a control program executed by the control unit 130.

  The input processing unit 153 is connected to the remote control light receiving unit 154 and the operation panel 155. The remote control light receiving unit 154 receives an infrared signal transmitted from a remote control (not shown) and detects an operation of the remote control. The operation panel 155 includes a switch and outputs an operation signal corresponding to the switch operation to the input processing unit 153. The input processing unit 153 outputs operation data to the control unit 130 in response to the operation of the remote control detected by the remote control light receiving unit 154 and the operation of the operation panel 155.

  The correction processing unit 160 performs processing for correcting the image data processed by the image processing unit 125 so as to eliminate the in-plane display unevenness in the liquid crystal panel 112 </ b> A, and outputs the processed image data to the light modulation device 112. .

  FIG. 2 is a block diagram illustrating a configuration of the correction processing unit 160. FIG. 2 illustrates the image input unit 124, the image processing unit 125, and the light modulation device 112 together with the correction processing unit 160. FIG. 3 is a configuration diagram of the liquid crystal panel 112A and the liquid crystal driver 114.

  As shown in FIG. 2, the light modulation device 112 includes a liquid crystal driver 114 and a display timing generation unit 115 in addition to the liquid crystal panel 112A. The liquid crystal driver 114 and the display timing generation unit 115 operate under the control of the control unit 130 and draw an image on the liquid crystal panel 112A. More specifically, the display timing generation unit 115 generates a clock (CLK) for driving the liquid crystal panel 112 </ b> A under the control of the control unit 130 and outputs the clock (CLK) to the liquid crystal driver 114. In addition, the display timing generation unit 115 generates a polarity inversion signal (INV) for instructing the timing of polarity inversion of the driving voltage of the liquid crystal panel 112A and outputs the polarity inversion signal (INV) to the liquid crystal driver 114 as described later.

  FIG. 3 illustrates the configuration of an active matrix driving system as an embodiment of the present invention. In the configuration of FIG. 3, the plurality of pixels 112B are arranged in a matrix. The liquid crystal driver 114 includes an X-direction driver 114A that selects pixels in the horizontal direction (X direction) and writes image data, and a Y-direction driver 114B that selects pixels in the vertical direction (Y direction).

The liquid crystal panel 112A includes an array substrate (not shown). In the array substrate, a plurality of scanning lines 101 extending in the X direction and a plurality of signal lines 102 extending in the Y direction are arranged in a matrix. Pixels (display elements) 103 are arranged at the intersections of the scanning lines 101 and the signal lines 102. The pixel 103 is composed of, for example, a pixel electrode and a thin film transistor (TFT) as a switching element. The TFT has a gate electrode connected to the scanning line 101, a source electrode connected to the signal line 102, and a drain electrode connected to the pixel electrode. These constitute the active matrix portion.
The liquid crystal panel 112A includes a counter substrate (not shown) on which a counter electrode facing the array substrate is formed, and holds a liquid crystal material between the array substrate and the counter substrate with an alignment film interposed therebetween.

  The Y-direction driver 114B is connected to each scanning line 101 provided in the liquid crystal panel 112A. A vertical synchronization signal (VSYNC) and a clock (CLK) are input to the Y-direction driver 114B. The Y-direction driver 114B scans the active matrix portion in the vertical direction according to the vertical synchronization signal and the clock, and sequentially selects the scanning lines 101.

  The X direction driver 114A is connected to each signal line 102 of the liquid crystal panel 112A. Image data (DATA), channel selection signal (CH), horizontal synchronization signal (HSYNC), polarity inversion signal (INV), and clock (CLK) are input to the X-direction driver 114A. The X-direction driver 114A scans the active matrix portion in the horizontal direction based on the horizontal synchronization signal and the clock, and sequentially selects the signal lines 102.

  The liquid crystal panel 112A employs a channel driving method. Each signal line 102 is divided into a plurality of channels. FIG. 3 shows an example in which a plurality of signal lines 102 are divided into four channels CH1 to CH4. The liquid crystal panel 112A outputs a driving voltage based on the image data to the signal line 102 for each channel in accordance with the channel selection signal.

  In this configuration, when the Y direction driver 114B selects the scanning line 101 and the X direction driver 114A selects the signal line 102, a driving voltage based on image data can be sent to the desired pixel 103. As a result, only the liquid crystal in the region sandwiched between the pixel electrode corresponding to the pixel 103 and the counter electrode changes its arrangement upon receiving the electric field between the electrodes and functions as a liquid crystal shutter for each pixel.

  The X-direction driver 114 </ b> A switches the polarity of the drive voltage applied to the signal line 102 in order to suppress deterioration of the liquid crystal panel 112 </ b> A caused by continuing to apply the DC voltage. The X-direction driver 114A switches the driving voltage of the signal line 102 between the positive electrode and the negative electrode according to the polarity inversion signal.

  Note that the liquid crystal panel 112 </ b> A may include a precharge drive circuit (not shown) and the like in addition to the X direction driver 114 </ b> A and apply a precharge voltage to each pixel 103. Further, the liquid crystal panel 112A may be configured to display a color image with three sub-pixels corresponding to three colors of R (red), G (green), and B (blue). In this case, the pixel 103 has one sub-pixel. Indicates a pixel.

In the liquid crystal panel 112A configured in this manner, the drive voltage output from the X-direction driver 114A to the signal line 102 is uneven due to the characteristics of the X-direction driver 114A or a circuit (not shown) attached to the X-direction driver 114A. There is. The X-direction driver 114A includes a D / A conversion circuit (not shown) that converts digital image data into an analog voltage for each channel. If there are variations in the characteristics of the D / A conversion circuit, the voltage value of the drive voltage of the X direction driver 114A will be different for each channel. This voltage difference causes a display color difference between the signal lines 102 having different channels, and is visually recognized as vertical stripe-like display unevenness along the direction of the signal line 102.
Therefore, in the present embodiment, the correction processing unit 160 corrects the image data input to the X-direction driver 114A for each channel, thereby suppressing the above-described display unevenness between channels.
Also, the appearance of display unevenness between channels may differ depending on the polarity of the driving voltage applied by the X-direction driver 114A. Therefore, the correction processing unit 160 corrects the image data so as to correspond to the channel and polarity.

  In addition, in-plane display unevenness may occur in the liquid crystal panel 112A. This type of display unevenness is, for example, a phenomenon in which the brightness and color appear to be different between the central portion and the end portion of the liquid crystal panel 112A. In the present embodiment, the correction processing unit 160 corrects the image data input to the X-direction driver 114A so as to correspond to the position in the surface, and suppresses the above-described display unevenness in the surface.

As shown in FIG. 2, the correction processing unit 160 includes a point selection unit 161, a channel selection unit 162, a polarity determination unit 163, an LUT (Lookup Table) selection unit 164, a correction amount LUT storage unit 165, and an interpolation processing unit 166. Prepare.
The image processing unit 125 outputs the image data (DATA) and the horizontal synchronization signal (HSYNC) on which the above-described image processing has been performed to the point selection unit 161. The point selection unit 161 acquires image data input by the image processing unit 125 in units of predetermined bytes. In the following description, a case where the point selection unit 161 acquires image data by 8 bytes is illustrated.
The point selection unit 161 specifies a display position where the input 8-byte image data is displayed on the liquid crystal panel 112A based on the horizontal synchronization signal. The display position specified by the point selection unit 161 is a position in the horizontal direction, and can be represented by the X coordinate corresponding to the X direction of the display area of the liquid crystal panel 112A or the number of the signal line 102.

After specifying the display position of the image data, the point selection unit 161 performs a process of selecting a point close to the display position.
In the liquid crystal panel 112A, points (representative positions) are set in advance at a plurality of locations in the horizontal direction. This point is a reference position where the correction processing unit 160 performs correction. In this embodiment, an example in which the number of signal lines 102 is 1280 and five points are set on the liquid crystal panel 112A will be described. In this example, the number of the leftmost signal line 102 in FIG. 3 is 0, the number of the rightmost signal line 102 is 1279, and the number of the signal line 102 is expressed as an X coordinate. If five points are set evenly in the horizontal direction of the liquid crystal panel 112A, the positions of the points are X = 128, 384, 640, 896, and 1152, respectively.

The point selection unit 161 specifies the X coordinate of the display position of the image data, that is, the number of the signal line 102, and selects one or two points close to the display position.
For example, when the X coordinate of the display position is outside the points at both ends, the point selection unit 161 selects one point. Specifically, when the X coordinate of the display position is less than 128, a point of X = 128 is selected, and when the X coordinate of the display position is larger than 1152, the point of X = 1152 is selected.
When the X coordinate of the display position matches the X coordinate of the point, the point selection unit 161 selects the matching point.
When the X coordinate of the display position is greater than 128 and less than 1152, and the X coordinate of the display position does not match the X coordinate of the point, the point selection unit 161 uses the point whose X coordinate is smaller than the display position and the display position. Select points with large X coordinates one by one.

  The point selection unit 161 outputs 8-byte image data and a horizontal synchronization signal to the channel selection unit 162. Here, the point selection unit 161 may output data indicating the display position of 8-byte image data to the channel selection unit 162 together with the image data. The point selection unit 161 outputs data indicating the selected point, and this data passes through the channel selection unit 162 and the polarity determination unit 163 and is input to the LUT selection unit 164.

The channel selection unit 162 selects a channel based on the display position of the image data input by the point selection unit 161. That is, the channel to which the image data belongs is selected from among CH1 to CH4 (FIG. 3) driven by the X-direction driver 114A.
The channel selection unit 162 outputs 8-byte image data and a horizontal synchronization signal to the polarity determination unit 163. Here, the channel selection unit 162 may output data indicating the display position of the 8-byte image data to the polarity determination unit 163 together with the image data. Further, the channel selection unit 162 outputs data indicating the selected channel, and this data passes through the polarity determination unit 163 and is input to the LUT selection unit 164.

  A polarity inversion signal (INV) generated by the display timing generation unit 115 of the light modulation device 112 is input to the polarity determination unit 163. The polarity determination unit 163 determines the polarity of the drive voltage when the X-direction driver 114A writes the image data input from the channel selection unit 162 to the signal line 102 based on the polarity inversion signal. The polarity determination unit 163 outputs data indicating the polarity determined based on the polarity inversion signal to the LUT selection unit 164. This data is, for example, data indicating whether the polarity of the drive voltage is positive or negative.

Data indicating the point selected by the point selection unit 161, data indicating the channel selected by the channel selection unit 162, and data indicating the polarity of the drive voltage determined by the polarity determination unit 163 are input to the LUT selection unit 164. The Further, image data may be input to the LUT selection unit 164. Further, a horizontal synchronization signal may be input.
The LUT selection unit 164 selects an LUT used for correction from a plurality of correction amounts LUT (correction data) stored in the correction amount LUT storage unit 165 and outputs the selected LUT to the interpolation processing unit 166.

FIG. 4 schematically shows the configuration of the correction amount LUT storage unit 165.
The correction amount LUT storage unit 165 stores a plurality of correction amounts LUT. The correction amount LUT is an LUT that converts image data processed by the image processing unit 125 so as to compensate for display unevenness of the liquid crystal panel 112A, and corresponds to correction data of the present invention.
Each correction amount LUT stored in the correction amount LUT storage unit 165 corresponds to a point, a channel (CH), and the polarity of the drive voltage. For example, the correction amount LUT corresponding to the point of X = 128 is the eight correction amount LUTs LUT11 to 14, 21 to 24. These eight correction amounts LUT correspond to the four channels and the positive and negative electrodes of the drive voltage. In the present embodiment, the number of points is 5 and the number of channels is 4. Therefore, in the example of FIG. 4, the correction amount LUT is 40.

  The LUT selection unit 164 acquires the number of correction amounts LUT corresponding to the number of points selected by the point selection unit 161 from the correction amount LUT storage unit 165. For example, when the point selection unit 161 selects two points, the LUT selection unit 164 acquires two correction amount LUTs. The correction amount LUT acquired by the LUT selection unit 164 is output to the interpolation processing unit 166.

The interpolation processing unit 166 determines whether or not to perform an interpolation operation on the correction amount LUT acquired by the LUT selection unit 164. The interpolation processing unit 166 determines to perform the interpolation calculation when the point selected by the point selection unit 161 does not match the display position of the image data. The interpolation processing unit 166 performs an interpolation operation on the correction amount LUT acquired by the LUT selection unit 164 and generates a new correction amount LUT.
Although various interpolation calculation methods are known, in this embodiment, the interpolation processing unit 166 performs linear interpolation processing. The interpolation processing unit 166 linearly interpolates the value included in the correction amount LUT corresponding to the point at a position different from the display position with reference to the X coordinate of the display position to obtain a value corresponding to the X coordinate of the display position. . The interpolation processing unit 166 creates a new correction amount LUT including the obtained value. The correction amount LUT created by the interpolation processing unit 166 matches the channel and polarity of the image data and matches the X coordinate of the display position.

By storing a different correction amount LUT for each point set in the X direction of the liquid crystal panel 112A and using a plurality of correction amounts LUT, the above-described display unevenness in the surface of the liquid crystal panel 112A can be suppressed. In other words, the correction amount LUT stored in the correction amount LUT storage unit 165 is a correction amount LUT that can compensate for in-plane display unevenness for each horizontal position on the liquid crystal panel 112A. Therefore, when the display position coincides with the position of the point, if the image data is corrected using the correction amount LUT corresponding to the point, the influence of display unevenness in the plane can be effectively suppressed. However, when the display position does not match the position of the point, the state of display unevenness in the plane is different, and thus the correction effect is limited even if the image data is corrected. Therefore, in the present embodiment, the interpolation processing unit 166 creates a correction amount LUT suitable for the display position by linearly interpolating the value of the correction amount LUT corresponding to the point.
The display unevenness in the surface of the liquid crystal panel 112A changes slowly in the horizontal direction, and in many cases, the display state changes in one direction from the center to the end of the liquid crystal panel 112A. Accordingly, it is possible to obtain a more appropriate correction value by performing linear interpolation (linear interpolation) on the value used for correcting the image data and obtaining a value corresponding to the X coordinate of the display position.

When the new correction amount LUT is created by the interpolation process, the interpolation processing unit 166 outputs the created correction amount LUT to the correction unit 167. If it is determined not to perform complement processing, the correction amount LUT selected by the LUT selection unit 164 is output to the correction unit 167.
The correction unit 167 performs correction processing based on the correction amount LUT input by the interpolation processing unit 166 on the image data processed by the image processing unit 125, and outputs the processed image data to the light modulation device 112.

  In this way, the correction processing unit 160 appropriately corrects the image data in accordance with the difference in the in-plane display unevenness at the display position, the display unevenness for each channel, and the display unevenness due to the polarity. Therefore, the display quality of the liquid crystal panel 112A can be improved, and the display quality of the projected image on the screen SC can be improved.

FIG. 5 is a flowchart showing the operation of the projector 100, and shows the operation of the correction processing unit 160 as a flowchart.
First, the point selection unit 161 acquires image data to be processed (step S11). The capacity of the image data acquired by the point selection unit 161 is set in advance, for example, corresponding to the amount of data that the liquid crystal driver 114 writes to the signal line 102 in one operation. The point selection unit 161 specifies the display position of the acquired image data, and selects a point close to the display position (step S12).
Next, the channel selection unit 162 selects a channel in which the X-direction driver 114A writes the image data to be processed (step S13). Further, the polarity determination unit 163 determines the polarity of the applied voltage when the X-direction driver 114A writes the drive voltage based on the image data to be processed (step S14).

Subsequently, the LUT selection unit 164 selects the correction amount LUT corresponding to the point selected in step S12, the channel selected in step S13, and the polarity determined in step S14 (step S15).
The interpolation processing unit 166 determines whether or not to perform the interpolation processing of the correction amount LUT selected by the LUT selection unit 164 (step S16). When performing the complementing process (step S16; Yes), the interpolation processing unit 166 creates a new correction amount LUT by the linear interpolation process (step S17), and proceeds to step S18. When the complement process is not performed (step S16; No), the interpolation processing unit 166 proceeds to step S18 as it is.

  In step S18, the correction unit 167 corrects the image data based on the correction amount LUT selected by the LUT selection unit 164 or the correction amount LUT generated by the interpolation processing unit 166 in the complementing process (step S18). As a result, the image data is corrected by the optimum correction amount LUT corresponding to the display position, channel, and polarity of the image data.

  The correction amount LUT stored in the correction amount LUT storage unit 165 can be added or rewritten by the control device 3 to which the I / F unit 156 is connected. For example, the LUT can be added or updated when the control program of the projector 100 stored in the storage unit 151 is rewritten. The rewriting of the control program of the projector 100 can be executed as a so-called firmware update. Therefore, the correction amount LUT stored in the correction amount LUT storage unit 165 can be updated as appropriate. In addition, the number of points set on the liquid crystal panel 112A and / or the X coordinate of the points can be changed. As a result, the correction amount LUT can be brought to the latest state in response to changes in characteristics of the liquid crystal driver 114 and the liquid crystal panel 112A with time.

  As described above, the projector 100 according to the embodiment to which the present invention is applied includes the liquid crystal panel 112A that displays an image based on image data, and the liquid crystal driver 114 that drives the liquid crystal panel 112A by dividing it into a plurality of channels. Have. The projector 100 includes a correction amount LUT storage unit 165 that stores a correction amount LUT corresponding to each channel and a point set in the horizontal direction of the liquid crystal panel 112A. Further, the image data displayed at the point is corrected based on the correction amount LUT and input to the liquid crystal panel 112A, and the image data displayed at a position other than the point is corrected by the interpolation calculation from the correction amount LUT. A correction unit 167 that performs correction based on the LUT and inputs it to the liquid crystal panel 112A is provided. For this reason, the projector 100 uses the correction amount LUT corresponding to the point of the liquid crystal panel 112A to both the display unevenness between the channels of the liquid crystal panel 112A and the display unevenness in the horizontal direction of the liquid crystal panel 112A. Corresponding corrections can be made. Thereby, display unevenness can be more reliably suppressed and display quality can be improved.

  The liquid crystal driver 114 is driven by outputting a voltage to the display element of the liquid crystal panel 112A, and performs polarity inversion to invert the polarity of the output voltage. The correction amount LUT storage unit 165 stores a correction amount LUT corresponding to each channel, a point set in the horizontal direction of the liquid crystal panel 112A, and the polarity of the output voltage of the liquid crystal driver 114. The correction unit 167 corrects the image data with a correction amount LUT corresponding to the polarity of the output voltage of the liquid crystal driver 114 when displaying the image data. Therefore, the projector 100 can correct the image data corresponding to the polarity when the liquid crystal panel 112A is driven by the polarity inversion method. Thereby, display unevenness can be more reliably suppressed and display quality can be improved.

Further, since the correction amount LUT, which is a look-up table for converting image data, is used as data used by the correction unit 167 for correction, the processing load for correcting the image data can be reduced.
Further, since the correction amount LUT stored in the correction amount LUT storage unit 165 can be written by the control device 3 that is an external device, for example, the correction amount LUT can be updated as necessary.
Further, the liquid crystal panel 112A includes a plurality of pixels 103 arranged in a matrix, and the correction unit 167 corrects image data displayed on each pixel 103 and inputs the corrected image data to the liquid crystal panel 112A. In other words, the configuration in which the plurality of pixels 103 arranged in a matrix is divided into a plurality of channels and driven so as to cope with both display unevenness between the channels of the liquid crystal panel 112A and display unevenness in the horizontal direction of the liquid crystal panel 112A. In addition, the image data can be corrected.

  The above-described embodiment is merely an example of a specific mode to which the present invention is applied, and the present invention is not limited. The present invention can be applied as a mode different from the above-described embodiment. For example, in the above embodiment, the correction unit 167 corrects the image data using the correction amount LUT corresponding to the point set corresponding to the display position on the liquid crystal panel 112A, the channel, and the polarity of the drive voltage. An example was explained. The present invention is not limited to this. For example, the correction data corresponding to the point, the correction data corresponding to the channel, and the correction data corresponding to the polarity of the drive voltage are stored in the correction amount LUT storage unit 165, respectively. May be. Then, the correction unit 167 acquires correction data corresponding to a point close to the image data, correction data corresponding to the channel of the image data, and correction data corresponding to the polarity at the time of writing the image data. May be performed. In this case, the correction unit 167 may correct the image data to reflect a plurality of correction data. When the display position of the image data does not coincide with the point, new correction data may be generated by linearly interpolating correction data corresponding to the point close to the image data. As described above, the specific configuration of the correction data is arbitrary, and one correction data does not need to correspond to each element of point, channel, and polarity. It is of course possible to use correction data that is not in the form of an LUT.

Further, for example, in the above-described embodiment, the active matrix driving type liquid crystal panel 112A has been described as an example. However, the present invention may be applied to a liquid crystal panel employing another driving method such as a simple matrix driving method. Is possible. Moreover, in the said embodiment, although the front projection type projector 100 which projects from the front of the screen SC was shown as an example of a display apparatus, this invention is not limited to this. For example, a rear projection (rear projection) type projector that projects from the back side of the screen SC can be employed as the display device. In addition, the present invention is applicable to any display device that has a display panel such as an organic EL (Electro Luminescence) display, a plasma display, and an SED (Surface-conduction Electron-emitter Display), and displays voltage by applying a voltage to the display panel. Applicable.
In the above-described embodiment, the correction processing unit 160 included in the projector 100 that displays an image has been described as an example of a configuration that functions as the image processing apparatus of the present invention. However, the present invention is not limited to this. An image processing device configured separately from the display device including the projector 100 may correct the image data as the correction processing unit 160.

  Moreover, each function part shown in FIG.1 and FIG.2 shows a functional structure, and a specific mounting form is not restrict | limited in particular. That is, it is not always necessary to mount hardware corresponding to each function unit individually, and it is of course possible to adopt a configuration in which the functions of a plurality of function units are realized by one processor executing a program. In addition, in the above embodiment, a part of the function realized by software may be realized by hardware, or a part of the function realized by hardware may be realized by software. In addition, the specific detailed configuration of each other part of the projector 100 can be arbitrarily changed without departing from the gist of the present invention.

  DESCRIPTION OF SYMBOLS 100 ... Projector (display apparatus), 101 ... Scanning line, 102 ... Signal line, 103 ... Pixel (display element), 110 ... Display part, 112 ... Light modulation apparatus, 112A ... Liquid crystal panel (display panel), 114 ... Liquid crystal driver 114A ... X direction driver, 114B ... Y direction driver, 115 ... display timing generation unit, 125 ... image processing unit, 130 ... control unit, 160 ... correction processing unit (image processing device), 161 ... point selection unit, 162 ... Channel selection unit, 163... Polarity determination unit, 164... LUT selection unit, 165... Correction amount LUT storage unit (correction data storage unit), 166... Interpolation processing unit, 167.

Claims (7)

A display panel for displaying images,
A driving unit that divides and drives the display panel into a plurality of channels;
A correction data storage unit that stores correction data corresponding to each of the channels and a representative position set in the horizontal direction of the display panel;
The image data displayed at the representative position is corrected based on the correction data and input to the display panel, and the image data displayed at a position other than the representative position is obtained by interpolation from the correction data. A correction unit that performs correction based on the interpolation correction data and inputs the correction to the display panel;
A display device comprising: The drive unit is to drive the display element of the display panel by outputting a voltage, and performs polarity inversion to invert the polarity of the output voltage,
The correction data storage unit stores the correction data corresponding to each of the channels, the representative position set in the horizontal direction of the display panel, and the polarity of the output voltage of the driving unit,
The correction unit corrects the image data with the correction data corresponding to the polarity of the output voltage of the drive unit when displaying the image data;
The display device according to claim 1. The correction data is a lookup table for converting image data,
The display device according to claim 1, wherein the correction data storage unit stores the lookup table.   The display device according to claim 1, wherein the correction data stored in the correction data storage unit can be written by an external device. The display panel includes a plurality of display elements arranged in a matrix,
The correction unit corrects image data displayed on each display element and inputs the corrected image data to the display panel;
The display device according to claim 1, wherein: An image processing apparatus for processing image data displayed on a display panel,
A correction data storage unit that stores correction data corresponding to each of the channels obtained by dividing the display panel and a representative position set in the horizontal direction of the display panel;
The image data displayed at the representative position is corrected based on the correction data and input to the display panel, and the image data displayed at a position other than the representative position is obtained by interpolation from the correction data. A correction unit that performs correction based on the interpolation correction data and inputs the correction to the display panel;
An image processing apparatus comprising: A control method for a display device including a display panel,
Storing correction data corresponding to each of the channels obtained by dividing the display panel and the representative position set in the horizontal direction of the display panel;
The image data displayed at the representative position is corrected based on the correction data and input to the display panel, and the image data displayed at a position other than the representative position is obtained by interpolation from the correction data. Correction based on the interpolation correction data, input to the display panel,
Driving the display panel into a plurality of channels based on the corrected image data;
A control method of a display device characterized by the above.

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