To provide a backlight brightness controlling apparatus and an image display apparatus which can suppress occurrence of brightness bleeding.
In the image display apparatus, the backlight 12 which illuminates a liquid crystal panel (image display panel) 11 is segmented into a plurality of areas. A frequency distribution processing section 14 calculates the amount of dark pixels from frequency distribution of gradation values of pixels in an image based on an image signal. A backlight controlling section 13 calculates a lower limit value of brightness in the plurality of areas included in the backlight 12 so as to increase the brightness when the amount of dark pixels is smaller, adjusts the brightness in each area individually according to the gradation value of each part of the image, and adjusts the brightness to the lower limit value of the brightness in an area where the brightness is lower than the lower limit value. A difference of brightness between areas which illuminate a dark part of the image in the backlight 12 is reduced, thereby suppressing the occurrence of brightness bleeding caused by the difference of the brightness between the areas.
TAKAKU KOICHI
KONO YOSHINORI
NAGASHIMA SHINICHI
YAGISAWA HIDEHITO
YAMADA KODAI
| JP2007240858A | 2007-09-20 | |||
| JP2009128608A | 2009-06-11 | |||
| JP2008009415A | 2008-01-17 |
| WO2009096068A1 | 2009-08-06 |
Hideno Kono
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