VIDEO DISPLAY APPARATUS
1 Assignment
0 Petitions
Accused Products
Abstract
Light leakage and black float are reduced in dark ambient while a perception of high contrast is achieved when a backlight is divided into a plurality of areas and backlight brightness is controlled depending on a video signal corresponding to each area. An area active control portion (2) divides a video signal into a plurality of areas and outputs a first feature value for each area. An LED control portion (3) acquires a first brightness for each divided area of an LED backlight (5) depending on the first feature value of each area, and acquires a second brightness for each area that is acquired by uniformly multiplying a specific multiplying factor acquired depending on the lighting ratio of the LED backlight (5) with respect to the first brightness within a range where a total value of the LED driving current does not exceed a predetermined permissible current value. When the lighting ratio of the LED backlight (5) is at or below a predetermined value, the second brightness is reduced in accordance with ambient lighting detected by a photosensor (8) to acquire a third brightness.
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Citations
10 Claims
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1-5. -5. (canceled)
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6. A video display apparatus comprising:
- a display panel that displays a video signal;
a backlight that uses LEDs as a light source illuminating the display panel;
a control portion that controls a light emission brightness of the backlight; and
an ambient illuminance detecting portion that detects ambient illuminance, the control portion dividing the backlight into a plurality of areas and controlling light emission of the LEDs for each of the divided areas, whereinthe control portion acquires a first brightness of the LEDs for each area depending on a first feature value of the video signal of a display area corresponding to the divided area, acquires a second brightness for each area by uniformly multiplying the first brightness by a specific multiplying factor acquired depending on a lighting rate of the backlight or a second feature value of the video signal, within a range where a total value of driving currents of the LEDs is equal to or lower than a predetermined permissible current value, and acquires a third brightness by reducing the second brightness depending on an ambient illuminance detected by the ambient illuminance detecting portion when the lighting rate of the backlight or the second feature value of the video signal is equal to or lower than a predetermined value. - View Dependent Claims (7, 8, 9, 10)
- a display panel that displays a video signal;
Specification