US 9,001,023 B2Granted

Liquid crystal display apparatus

AssigneeSharp Kabushiki Kaisha

InventorsTamaki Mashiba, Junko Yabuta

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Abstract

Adjustment of white balance based on a measurement result of light emission luminance of a backlight is allowed to be executed accurately and effectively. A backlight luminance detection portion detects light emission luminance of an LED backlight in a state where an optical shutter of a liquid crystal display panel is closed. A main control portion adjusts light emission luminance of the LED backlight according to light emission luminance detected by the backlight luminance detection portion. Here, the main control portion compares light emission luminance of LEDs of RGB detected by the backlight luminance detection portion with light emission luminance of RGB in white balance adjustment that is stored in advance in the storage portion, and adjusts, when an error occurs between the compared light emission luminance, the light emission luminance of each of the LEDs of RGB so as to eliminate the error.

Claims4

Dependent claims

A liquid crystal display apparatus comprising:

a liquid crystal display panel;
a backlight for illuminating the liquid crystal display panel from a back side thereof;
a control portion for controlling the liquid crystal display panel and the backlight;
a backlight luminance detection portion for detecting light emission luminance of the backlight on the back side of the liquid crystal display panel;
and
an ambient illuminance detection portion for detecting ambient illuminance of the liquid crystal display apparatus, wherein
when ambient illuminance detected by the ambient illuminance detection portion is higher than a predetermined threshold, the backlight luminance detection portion detects light emission luminance of the backlight in a state where an optical shutter of the liquid crystal display panel is closed, and the control portion adjusts light emission luminance of the backlight according to the light emission luminance detected by the backlight luminance detection portion, and
when ambient illuminance detected by the ambient illuminance detection portion is not higher than a predetermined threshold, the backlight luminance detection portion does not detect light emission luminance of the backlight.

5 more elements

Dependencies are inferred from the claim text.

Facts

Application: 13/658,770Filed 23 Oct 2012
Priority: JP 2011-23454326 Oct 2011
Published: US 2013/0106680 A12 May 2013
Granted: 7 Apr 2015
Term ends: Not estimatedThe source records don’t support an estimate.

Classification6 codes

G09G 3/3413
Control of illumination source: details of control of colour illumination sources
G09G 3/36
By control of light from an independent source: using liquid crystals
G09G 2320/0666
Adjustment of display parameters: for control of colour parameters, e.g. colour temperature
G09G 2360/14
Aspects of the architecture of display systems: detecting light within display terminals, e.g. using a single or a plurality of photosensors