Title:
液晶表示装置、電子機器及び前記液晶表示装置の照光手段の明るさを制御する方法
Document Type and Number:
Japanese Patent JP4462293
Kind Code:
B2
Abstract:
A liquid crystal display according to an embodiment of the present invention includes a liquid crystal display panel, an illumination unit for the liquid crystal display panel, a plurality of photodetectors, and a control unit Cnt to control the brightness of the illumination unit. The photodetectors are TFT ambient light photosensors LS1 to LS3, for example, which produce outputs that require time to reach a predetermined value, which the time is correlated with the intensity of ambient light. Detection circuits coupled to the photodetectors include circuits (Cmp1 to Cmp3) logically inverted when an output from the TFT ambient light photosensors LS1 to LS3 reaches a predetermined value. The control unit Cnt includes a discrimination implement Maj that determines that the intensity of ambient light has changed when outputs from the majority of the detection circuits are logically inverted. The above-mentioned structure provides a liquid crystal display that does not use plurality of interface circuits nor A/D converters, nor experience frequent malfunctions for automatic control of the brightness of the illumination unit according to the intensity of ambient light.
Inventors:
Yasushi Yamazaki
Takashi Kunimori
Masanori Yasumori
Takashi Kunimori
Masanori Yasumori
Application Number:
JP2007146546A
Publication Date:
May 12, 2010
Filing Date:
June 01, 2007
Export Citation:
Assignee:
Epson Imaging Device Co., Ltd.
International Classes:
G09G3/36; G02F1/133; G09G3/20; G09G3/34
Domestic Patent References:
| JP2007102025A | ||||
| JP2005189853A | ||||
| JP2006253236A | ||||
| JP2007047789A | ||||
| JP2005345286A | ||||
| JP2006243655A | ||||
| JP2004070195A | ||||
| JP4254820A | ||||
| JP11282401A | ||||
| JP2007199274A | ||||
| JP2008026688A | ||||
| JP2007310096A |
Attorney, Agent or Firm:
Masahiko Ueyanagi
Osamu Suzawa
Kazuhiko Miyasaka
Osamu Suzawa
Kazuhiko Miyasaka