Abstract: An image display apparatus includes a display panel including multiple pixels, a backlight including multiple white-light light sources, a panel driving circuit, a backlight driving circuit, and a determination circuit determining image data. The white-light light sources have characteristics that cause afterglow of a particular color to persist longer than afterglow of another color. The backlight driving circuit segments the backlight into multiple areas and drives the backlight such that a time duration of performing control to cause the areas to sequentially be in a light-emission state at mutually different timings alternates with a time duration of performing control to cause all the areas to be in a non-light-emission state. The determination circuit determines a determination value indicating a degree of inclusion at which achromatic data is included in the image data and determines a light-emission start timing of each of the areas in accordance with the determination value.

Abstract: In an image display device having a backlight including a plurality of light sources, the backlight is divided into a plurality of areas arranged in the same direction as an order of writing to pixels. A backlight drive circuit sets lighting periods separately for each of the areas and causes the brightness of the light sources to rise and drop in a non-step manner during the corresponding lighting period. In a case where first and second areas are adjacent to each other, there is a period of overlap between a lighting period set for the first area and a lighting period set for the second area, and the period of overlap includes a middle portion in which the brightness of light sources corresponding to the first area drops and the brightness of light sources corresponding to the second area rises.

Abstract: An image display device 1 includes an image data conversion unit 10 that performs conversion processing of converting input image data D1 into driving image data D2 for each pixel, and a display unit 20 that displays a plurality of subframes based on the driving image data D2, in one frame period. In the conversion processing in the image data conversion unit 10, for each pixel, the hue and the saturation of the input image data D1 and the hue and the saturation of the driving image data D2 in an HSV color space are held to be respectively equal to each other. The image data conversion unit 10 computes a coefficient Ks used in the conversion processing, and performs the conversion processing using the coefficient Ks. The coefficient Ks varies depending on a brightness V and has a value causing a brightness after the conversion processing to increase as the brightness V becomes greater if the saturations S are equal to each other.

Abstract: An image display device 1 includes an image data conversion unit 10 that performs conversion processing of converting input image data D1 into driving image data D2 for each pixel, and a display unit 20 that displays a plurality of subframes based on the driving image data D2, in one frame period. In the conversion processing in the image data conversion unit 10, for each pixel, the hue and the saturation of the input image data D1 and the hue and the saturation of the driving image data D2 in an HSV color space are held to be respectively equal to each other. The image data conversion unit 10 computes a coefficient Ks used in the conversion processing, and performs the conversion processing using the coefficient Ks. The coefficient Ks varies depending on a brightness V and has a value causing a brightness after the conversion processing to increase as the brightness V becomes greater if the saturations S are equal to each other.

Abstract: In an image display device having a backlight including a plurality of light sources and an image display method, the backlight is divided into a plurality of areas arranged in the same direction as an order of writing to pixels. A backlight drive circuit sets lighting periods separately for each of the areas and causes the brightness of the light sources to rise and drop in a non-step manner during the corresponding lighting period. In a case where a first area and a second area are adjacent to each other, there is a period of overlap between a lighting period set for the first area and a lighting period set for the second area, and the period of overlap includes a middle portion in which the brightness of light sources corresponding to the first area drops and the brightness of light sources corresponding to the second area rises.

Abstract: An image display device includes an image data conversion unit that performs conversion processing of input image data and a display unit that displays a plurality of subframes, in one frame period. In the image data conversion unit, the conversion processing is performed in a manner that, for each pixel, a hue and a saturation of the input image data and a hue and a saturation of driving image data in an HSV color space are held to be respectively equal to each other, color components of the driving image data are set to have the same value when the saturation of the input image data is equal to the minimum saturation, and when the saturation of the input image data is equal to the maximum saturation, the color components of the input image data are multiplied by the same value, and then the input image data is compressed.

Abstract: With a field sequential method, image display having sufficiently high color reproduction is performed, and an occurrence of color breakup is more reliably suppressed. In a field sequential liquid crystal display apparatus in which a plurality of subframes including a red subframe, a green subframe, a blue subframe, and a white (common color) subframe constitutes each frame, an image data conversion unit (30) converts input image data (D1) corresponding to red, green, and blue into driving image data (D2) corresponding to the plurality of subframes, based on an adjustment coefficient (Ks) and a distribution ratio (WRs) for the white subframe, for each pixel. Two distribution ratios are selectively used as the distribution ratio (WRs). A function of obtaining a second distribution ratio (WRsv2) of the two distribution ratios is set such that the distribution ratio (WRsv2) increases as the adjusted brightness (brightness after amplification and compression processing) (V) for an input image becomes smaller.

Abstract: An image display device includes an image data conversion unit (10) that performs conversion processing of converting input image data (D1) into driving image data (D2) for each pixel, and a display unit (20) that displays a plurality of subframes based on the driving image data (D2), in one frame period. In the image data conversion unit (10), the conversion processing is performed in a manner that, for each pixel, a hue and a saturation of the input image data (D1) and a hue and a saturation of the driving image data (D2) in an HSV color space are held to be respectively equal to each other, color components of the driving image data (D2) are set to have the same value when the saturation of the input image data (D1) is equal to the minimum saturation, and, when the saturation of the input image data (D1) is equal to the maximum saturation, the color components of the input image data (D1) are multiplied by the same value, and then the input image data (D1) is compressed.

Abstract: An image display device includes a display panel having a uniform resolution, an image data conversion unit for converting first image data including a plurality of pieces of pixel data to second image data including a smaller number of pieces of pixel data, and a drive circuit for driving the display panel based on the second image data. The display panel has a first region in which one piece of the pixel data is written to one pixel and a second region in which one piece of the pixel data is written to two or more pixels, and has a third region and a fourth region. The image data conversion unit performs a calculation on the pixel data of the pixel in the fourth region, the calculation performed in accordance with a distance of the pixel from a reference position, and does not perform the calculation on the pixel data of the pixel in the third region.

Abstract: A light source section 21 includes a red light source 22r, a green light source 22g, and a blue light source 22b, and one frame period is divided into four subfield periods. Light sources of each color respectively emit light in blue, green, and red subfield periods, and the red light source 22r and the green light source 22g emit light in a yellow subfield period. Light emission intensity of the blue light source 22b in the blue subfield period is set to twice light emission intensities of the red light source 22r and the green light source 22g in other subfield periods. Color breakup is reduced by displaying the yellow subfield, and light utilization efficiency improved by setting transmittance of a light modulation element 16 to 100% when a white signal by which each gradation of red, green, and blue becomes maximum is input. With this, a field sequential type display device which can reduce color breakup and has high light utilization efficiency is provided.

Abstract: In a field sequential type liquid crystal display apparatus in which each frame period is configured with first to fourth transparent subframe periods and blue, green, white, and blue subframe periods, a backlight unit is driven as follows. Light sources are in a turn-off state in the transparent subframe periods. In a second half of the blue, green, and red subframe periods, each of blue, green, and red light sources is in a turn-on state. In a second half of a white subframe, all light sources are in the turn-on state. Driving image data that corresponds to such a configuration of the frame period is generated from input image data, and a liquid crystal panel is driven based on the driving image data.

Abstract: A liquid crystal display device of a time division driving system, capable of preventing an occurrence of a color shift without causing flickering or image sticking, is achieved. The liquid crystal display device includes: a stable arrival gradation data acquisition unit (122) configured to acquire stable arrival gradation data indicating an arrival gradation estimation value at a start timing of each field of the last frame, in a case where a virtual display process of three or more frames is performed based on input gradation data for one frame; and an input gradation data compensation unit configured to acquire writing gradation data by compensating the input gradation data based on the stable arrival gradation data.

Abstract: Image display having high color reproducibility is performed with preventing an occurrence of color breakup while a decrease of light utilization efficiency is prevented. In a field sequential liquid crystal display apparatus in which a frame is configured with a red subframe, a green subframe, a blue subframe, and a white (common color) subframe, an image data conversion unit 30 converts input image data D1 corresponding to a red color, a green color, and a blue color into driving image data D2 corresponding to a plurality of subframes, for each pixel.

Abstract: With a field sequential method, image display having sufficiently high color reproduction is performed, and an occurrence of color breakup is more reliably suppressed. In a field sequential liquid crystal display apparatus in which a plurality of subframes including a red subframe, a green subframe, a blue subframe, and a white (common color) subframe constitutes each frame, an image data conversion unit (30) converts input image data (D1) corresponding to red, green, and blue into driving image data (D2) corresponding to the plurality of subframes, based on an adjustment coefficient (Ks) and a distribution ratio (WRs) for the white subframe, for each pixel. Two distribution ratios are selectively used as the distribution ratio (WRs). A function of obtaining a second distribution ratio (WRsv2) of the two distribution ratios is set such that the distribution ratio (WRsv2) increases as the adjusted brightness (brightness after amplification and compression processing) (V) for an input image becomes smaller.

Abstract: A light source section 21 includes a red light source 22r, a green light source 22g, and a blue light source 22b, and one frame period is divided into four subfield periods. Light sources of each color respectively emit light in blue, green, and red subfield periods, and the red light source 22r and the green light source 22g emit light in a yellow subfield period. Light emission intensity of the blue light source 22b in the blue subfield period is set to twice light emission intensities of the red light source 22r and the green light source 22g in other subfield periods. Color breakup is reduced by displaying the yellow subfield, and light utilization efficiency improved by setting transmittance of a light modulation element 16 to 100% when a white signal by which each gradation of red, green, and blue becomes maximum is input. With this, a field sequential type display device which can reduce color breakup and has high light utilization efficiency is provided.

Abstract: An image display device includes a display panel having a uniform resolution, an image data conversion unit for converting first image data including a plurality of pieces of pixel data to second image data including a smaller number of pieces of pixel data, and a drive circuit for driving the display panel based on the second image data. The display panel has a first region in which one piece of the pixel data is written to one pixel and a second region in which one piece of the pixel data is written to two or more pixels, and has a third region and a fourth region. The image data conversion unit performs a calculation on the pixel data of the pixel in the fourth region, the calculation performed in accordance with a distance of the pixel from a reference position, and does not perform the calculation on the pixel data of the pixel in the third region.

Abstract: A subframe data generation unit 12 generates brightness data Ew, Er, Eg, Eb of four colors by obtaining distributed brightness with regard to each pixel based on brightness data Dr, Dg, Db of three colors, the distributed brightness being brightness of a white subframe, and obtaining brightness of red, green, and blue subframes with regard to each pixel based on the brightness data Dr, Dg, Db of three colors and the distributed brightness. The subframe data generation unit 12 obtains the distributed brightness by setting an initial value of the distributed brightness to a maximum value that the distributed brightness can take, and then performing adjustment processing for reducing a difference between the distributed brightness of adjacent pixels. With this, a flicker phenomenon occurring at an edge portion of a display image is suppressed.

Abstract: A subframe data generator 12 determines a distribution color X which is a color of a variable color subframe, and then selects pixels sequentially to perform the following processing on the selected pixel P. Distributed brightness (Dsr, Dsg, Dsb) is calculated based on brightnesses Dr, Dg, Db and the distribution color X, and a distribution ratio ? is set to a value of 1 at which color breakup is the smallest. An evaluation value Qi related to a color difference when a line of sight moves is calculated based on brightness of the selected pixel P, brightnesses of neighboring pixels Pi (i=1 to N), and the distribution color X, and the distribution ratio ? is decreased in steps until the maximum value Qmax of the evaluation value Qi is less than or equal to a threshold value Qth. The brightnesses Dr, Dg, Db of three colors are converted to brightnesses Ex, Er, Eg, Eb of four colors based on the distribution color X and the distribution ratio ? determined for each pixel.

Abstract: In a field sequential type liquid crystal display apparatus in which each frame period is configured with first to fourth transparent subframe periods and blue, green, white, and blue subframe periods, a backlight unit is driven as follows. Light sources are in a turn-off state in the transparent subframe periods. In a second half of the blue, green, and red subframe periods, each of blue, green, and red light sources is in a turn-on state. In a second half of a white subframe, all light sources are in the turn-on state. Driving image data that corresponds to such a configuration of the frame period is generated from input image data, and a liquid crystal panel is driven based on the driving image data.

Abstract: A liquid crystal display device employing a field sequential system includes: a color correction unit (122) configured to perform a color correction processing that changes a saturation of input gradation data representing a color of a pixel without changing a hue thereof and configured to output pixel data obtained by the color correction processing as digital gradation data (D1 to D3) which are data corresponding to each field; and a digital gradation data correction unit configured to perform correction that enhances a temporal change of data values of digital gradation data (D1 to D3) outputted from the color correction unit (122). The color correction unit (122) performs the color correction processing on the input gradation data such that a color based on pixel data obtained by the color correction processing is a color that can be displayable in the liquid crystal panel by the field sequential system.