Abstract: A method of controlling a backlight of a display device is disclosed. The display device includes a display panel and the backlight. The backlight includes a plurality of backlight blocks. The method determines provisional luminance values for the plurality of backlight blocks in accordance with an input video frame. The method adjusts the provisional luminance values by amounts of reduction based on a total sum of the provisional luminance values and individual provisional luminance values.

Abstract: A controller acquires video data, determines provisional luminance values for backlight blocks based on the video data, determines an adjustment coefficient for a backlight block of interest selected from the backlight blocks, determines an adjusted luminance value for the backlight block of interest based on the provisional luminance value and the adjustment coefficient for the backlight block of interest, and controls the backlight block of interest in accordance with the adjusted luminance value. In determining the adjustment coefficient, the controller calculates a statistic of provisional luminance values for reference backlight blocks including backlight blocks adjacent to the backlight block of interest, calculates a relative value of the statistic with respect to the provisional luminance value for the backlight block of interest, and determines the adjustment coefficient for the backlight block of interest based on the relative value and a predefined function.

Abstract: Disclosed is a method of controlling a backlight for of a display panel. The backlight includes backlight blocks. The display panel includes display region blocks opposite to the backlight blocks in one-to-one correspondence. The method determines, for each of the backlight blocks, a luminance value demanded from each of pixels in display region blocks including a display region block opposite to the backlight block and one or more display region blocks adjacent to the opposite display region block to the backlight block based on a luminance value of the pixel and a weight determined depending on a relation of a location of the pixel and a location of the backlight block. The method determines, for each of the backlight blocks, a highest value among the demanded luminance values for the backlight block to be a luminance value for the backlight block.

Abstract: A controller acquires video data, determines provisional luminance values for backlight blocks based on the video data, determines an adjustment coefficient for a backlight block of interest selected from the backlight blocks, determines an adjusted luminance value for the backlight block of interest based on the provisional luminance value and the adjustment coefficient for the backlight block of interest, and controls the backlight block of interest in accordance with the adjusted luminance value. In determining the adjustment coefficient, the controller calculates a statistic of provisional luminance values for reference backlight blocks including backlight blocks adjacent to the backlight block of interest, calculates a relative value of the statistic with respect to the provisional luminance value for the backlight block of interest, and determines the adjustment coefficient for the backlight block of interest based on the relative value and a predefined function.

Abstract: A method of controlling a backlight of a display device is disclosed. The display device includes a display panel and the backlight. The backlight includes a plurality of backlight blocks. The method determines provisional luminance values for the plurality of backlight blocks in accordance with an input video frame. The method adjusts the provisional luminance values by amounts of reduction based on a total sum of the provisional luminance values and individual provisional luminance values.

Abstract: Disclosed is a method of controlling a backlight for of a display panel. The backlight includes backlight blocks. The display panel includes display region blocks opposite to the backlight blocks in one-to-one correspondence. The method determines, for each of the backlight blocks, a luminance value demanded from each of pixels in display region blocks including a display region block opposite to the backlight block and one or more display region blocks adjacent to the opposite display region block to the backlight block based on a luminance value of the pixel and a weight determined depending on a relation of a location of the pixel and a location of the backlight block. The method determines, for each of the backlight blocks, a highest value among the demanded luminance values for the backlight block to be a luminance value for the backlight block.

Abstract: A control signal generation circuit includes: a first circuit unit which controls, according to inputted video signals, light-up amount of each pixel of a display panel where a plurality of pixels constituted by including a white sub-pixel are disposed; and a second circuit unit which controls luminance of a backlight that lights up the display panel from a back surface. The second circuit unit calculates a saturation feature value in one frame from the saturation value of each pixel, generates a signal for controlling the luminance of the backlight based thereupon, and calculates a luminance increase rate by using the saturation value of each pixel and the saturation feature value. The first circuit unit performs luminance decreasing processing of each pixel according to the luminance increase rate, and supplements the saturation of each pixel according to the light-up amount of the white sub-pixels.

Abstract: A control circuit having large effects of low power consumption in CABC drive is provided. The control circuit performs B/L luminance reduction in eliminating a discomfort in image quality by using the feature value calculation circuit in the video signal. The control circuit comprises a luminance control circuit controlling a backlight luminance according to an inputted video signal and a gradation conversion circuit for converting a gradation of inputted video signal according to a controlled luminance. The control circuit reduces continuously and smoothly the backlight luminance, while the screen area reaches one-pixel white, in case where the all white is inputted as video signal, one-pixel black is displayed in any screen area from a display condition of all white, a rate of screen area displaying one-pixel black is gradually increased, and the video signal is continuously changed until the screen area of all white reaches the one-pixel white.

Abstract: The video signal processing circuit which analyzes video signals inputted from outside, performs conversion processing for image quality adjustment on the video signals based on a result of analysis, transmits those towards a video display unit includes: a feature value/maximum value calculation module which calculates a feature value that is a numerical value showing a degree of brightness of the video signals; a gradation conversion threshold value calculation module which calculates a threshold value regarding conversion of the gradation based on a threshold value calculation expression that is formed based on the feature value and a conversion coefficient set in advance; and a gradation conversion module which performs gradation conversion based on a linear function that increases linearly by taking a region of the gradation equal to or higher than the threshold value among the video signals as a target.

Abstract: A control circuit conducts a drive control of a RGBW display panel to operate white pixels to light up together with red, green and blue pixels, where the drive control includes a luminance control of a backlight to reduce luminance of the backlight according to an amount of an increase in luminance of the display panel due to a lighting operation of the white pixels. The control circuit includes: a first circuit section configured to generate control signals for controlling the display panel; and a second circuit section configured to generate control signals for controlling the backlight. The first circuit section includes a redistributing circuit section configured to distribute a luminance component of each white pixel to corresponding the red, green and blue pixels and reduce luminance of the each white pixel when the display panel has a white chromaticity dependence on gradation values.

Abstract: The present invention is directed to sufficiently reduce the level of EMI which occurs from a switching FET in a DC/DC converter and minimize deterioration in efficiency of a power supply. A DC/DC converter includes a switching circuit for driving a switching FET for increasing or decreasing voltage, and a switching circuit for driving a ringing frequency changing circuit. One end of a capacitor is connected to a drain of the switching FET for increasing or decreasing voltage, and the other end of the capacitor is connected to a drain of an FET for the ringing frequency changing circuit. A source of the FET for the ringing frequency changing circuit is connected to GND, and a control circuit is provided which makes the ringing frequency changing circuit valid so that a ringing frequency becomes low only in a ringing frequency component exerting large influence on deterioration in EMI.

Abstract: There are provided a DC/DC converter and a display device. The DC/DC converter includes: an inductor connected to an input terminal; a switching element connected between the inductor and the earth; a diode connected between the inductor and an output terminal; a capacitor connected between the output terminal and the earth; a feedback circuit connected between the output terminal and the earth and outputting a feedback voltage; and an oscillating circuit performing an ON/OFF control of the switching element at a frequency corresponding to the received feedback voltage. The DC/DC converter further includes: a detection circuit which detects an external magnetic field and outputs a signal that is different depending on whether or not the detected magnetic field exceeds a predetermined threshold; and a control circuit performing a control of the DC/DC converter according to the signal, to suppress an overcurrent of the DC/DC converter in a strong magnetic field.

Abstract: A control signal generation circuit includes: a first circuit unit which controls, according to inputted video signals, light-up amount of each pixel of a display panel where a plurality of pixels constituted by including a white sub-pixel are disposed; and a second circuit unit which controls luminance of a backlight that lights up the display panel from a back surface. The second circuit unit calculates a saturation feature value in one frame from the saturation value of each pixel, generates a signal for controlling the luminance of the backlight based thereupon, and calculates a luminance increase rate by using the saturation value of each pixel and the saturation feature value. The first circuit unit performs luminance decreasing processing of each pixel according to the luminance increase rate, and supplements the saturation of each pixel according to the light-up amount of the white sub-pixels.

Abstract: There are provided a DC/DC converter and a display device. The DC/DC converter includes: an inductor connected to an input terminal; a switching element connected between the inductor and the earth; a diode connected between the inductor and an output terminal; a capacitor connected between the output terminal and the earth; a feedback circuit connected between the output terminal and the earth and outputting a feedback voltage; and an oscillating circuit performing an ON/OFF control of the switching element at a frequency corresponding to the received feedback voltage. The DC/DC converter further includes: a detection circuit which detects an external magnetic field and outputs a signal that is different depending on whether or not the detected magnetic field exceeds a predetermined threshold; and a control circuit performing a control of the DC/DC converter according to the signal, to suppress an overcurrent of the DC/DC converter in a strong magnetic field.

Abstract: A control circuit conducts a drive control of a RGBW display panel to operate white pixels to light up together with red, green and blue pixels, where the drive control includes a luminance control of a backlight to reduce luminance of the backlight according to an amount of an increase in luminance of the display panel due to a lighting operation of the white pixels. The control circuit includes: a first circuit section configured to generate control signals for controlling the display panel; and a second circuit section configured to generate control signals for controlling the backlight. The first circuit section includes a redistributing circuit section configured to distribute a luminance component of each white pixel to corresponding the red, green and blue pixels and reduce luminance of the each white pixel when the display panel has a white chromaticity dependence on gradation values.

Abstract: This invention n provides a control circuit having large effects of low power consumption in CABC drive. The control circuit performs B/L luminance reduction in eliminating a discomfort in image quality by using the feature value calculation circuit in the video signal. The control circuit comprises a luminance control circuit controlling a backlight luminance according to an inputted video signal and a gradation conversion circuit for converting a gradation of inputted video signal according to a controlled luminance. The control circuit reduces continuously and smoothly the backlight luminance, while the screen area reaches one-pixel white, in case where the all white is inputted as video signal, one-pixel black is displayed in any screen area from a display condition of all white, a rate of screen area displaying one-pixel black is gradually increased, and the video signal is continuously changed until the screen area of all white reaches the one-pixel white.

Abstract: The video signal processing circuit which analyzes video signals inputted from outside, performs conversion processing for image quality adjustment on the video signals based on a result of analysis, transmits those towards a video display unit includes: a feature value/maximum value calculation module which calculates a feature value that is a numerical value showing a degree of brightness of the video signals; a gradation conversion threshold value calculation module which calculates a threshold value regarding conversion of the gradation based on a threshold value calculation expression that is formed based on the feature value and a conversion coefficient set in advance; and a gradation conversion module which performs gradation conversion based on a linear function that increases linearly by taking a region of the gradation equal to or higher than the threshold value among the video signals as a target.

Abstract: The degree of an influence from wiring crosstalk between signal lines of a data signal transmission line (video signal line) is decided on the basis of an input signal generated in display controlling unit (a timing controller) at a predetermined timing (at each frame period, at each clock pulse period, or at each horizontal period) and, based on a result of the decision, the voltage amplitude of a data signal is adjusted so that it may exceed an input amplitude specification value for data line driving circuits (data drivers) by a predetermined value.

Abstract: An image display device and a transmission signal control method to be used in same and more particularly to the image display device and the transmission signal control method that can be suitably used when transmission wirings for data signal based on a video signal become complicated due to configurations of a large-sized and high-definition image display device.

Abstract: The present invention is directed to sufficiently reduce the level of EMI which occurs from a switching FET in a DC/DC converter and minimize deterioration in efficiency of a power supply. A DC/DC converter includes a switching circuit for driving a switching FET for increasing or decreasing voltage, and a switching circuit for driving a ringing frequency changing circuit. One end of a capacitor is connected to a drain of the switching FET for increasing or decreasing voltage, and the other end of the capacitor is connected to a drain of an FET for the ringing frequency changing circuit. A source of the FET for the ringing frequency changing circuit is connected to GND, and a control circuit is provided which makes the ringing frequency changing circuit valid so that a ringing frequency becomes low only in a ringing frequency component exerting large influence on deterioration in EMI.