Image display apparatus
An image display apparatus includes a dimming value determination circuit for determining a dimming value of a backlight based on an input image signal, an image signal compensation circuit for compensating the input image signal supplied to a liquid crystal panel in accordance with the dimming value, and a backlight drive circuit for driving and controlling the backlight in accordance with the dimming value. When the light emitting luminance of the present frame of the backlight increases relative to the light emitting luminance of the previous frame, the backlight drive circuit delays the timing for applying the dimming value of the present frame. This makes it possible to reduce power consumption of the backlight by suppressing deterioration in the image quality in spite of the sharp change in the display image luminance.
1. An image display apparatus for displaying an image comprising:
a display liquid crystal panel formed by arranging a plurality of liquid crystal elements each having a light transmittance variable in accordance with a signal of an input image, the liquid crystal panel being divided into a plurality of regions;
a plurality of light sources which generate light for irradiating each one of the regions of the liquid crystal panel;
a dimming value determination unit which determines a dimming value for setting a light emitting luminance of each of the light sources based on the signal of the input image in the respective regions;
an image signal compensation unit which compensates the signal of the input image supplied to the liquid crystal panel for each of the regions in accordance with the dimming value corresponding to each of the light sources, which has been determined by the dimming value determination unit; and
a drive control unit which drives and controls the light sources in accordance with the dimming value corresponding to each of the light sources, which has been determined by the dimming value determination unit,
wherein
in the regions of the liquid crystal panel where the transmittance of the liquid crystal elements when applying the signal of the input image compensated in accordance with the dimming value of a present frame transitions lower than the transmittance of the liquid crystal elements when applying the signal of the input image compensated in accordance with the dimming value of a previous frame, and where the light emitting luminance of the light sources when applying the dimming value of the present frame increases compared to the light emitting luminance of the light sources when applying the dimming value of the previous frame, the drive control unit applies, to the light sources in said regions, the dimming value of the previous frame before the end of the transition of the liquid crystal elements and the dimming value of the present frame after the end of transition of the liquid crystal elements.
2. An image display apparatus for displaying an image comprising:
a liquid crystal display panel formed by arranging a plurality of liquid crystal elements each having a light transmittance variable in accordance with a signal of an input image, the liquid crystal panel being divided into a plurality of regions;
a plurality of light sources which generate light for irradiating each of the regions of the liquid crystal panel;
a dimming value determination unit which determines a dimming value for setting a light emitting luminance of each of the light sources based on the signal of the input image in the respective regions;
an image signal compensation unit which compensates the signal of the input image supplied to the liquid crystal panel for each of the regions in accordance with the dimming value corresponding to the light sources, which has been determined by the dimming value determination unit; and
a drive control unit which drives and controls the light sources in accordance with the diming value corresponding to each of the light sources, which has been determined by the dimming value determination unit,
wherein in the regions of the liquid crystal panel where the transmittance of the liquid crystal elements when applying the signal of the input image compensated in accordance with a first diming value transitions lower than the transmittance of the liquid crystal elements when applying the signal of the input image compensated in accordance with a second dimming value which is determined before the first dimming value, and where the light emitting luminance of the light sources when applying the first dimming value increases compared to the light emitting luminance of the light sources when applying the second dimming value,
the drive control unit applies, to the light sources in said regions, the second dimming value before the end of the transition of the liquid crystal elements and the first dimming value after the end of transition of the liquid crystal elements.