Liquid crystal display device


PURPOSE: To turn off a back light except when it is necessary for a liquid crystal display by turning off the back light when a timer means measures a time longer than a specific time and turning on the back light in the off state on detecting keying operation. CONSTITUTION: A main control part 13 supplies a reset signal 18 to a time monitoring timer 17 every time code information is sent from a keyboard device 16 to reset its clocking operation. When clocking the preset specific time, e.g. three minutes, the time monitoring timer 17 supplies a clocking end signal 19 to the main control part 13 and sends out a control signal for indicating the off operation of the back light to a back light illumination control signal 13. Therefore, when keying on a keyboard device 16 is not performed for the specific time, the back light 12 is turned off automatically. Consequently, the back light can be turned off except when necessary to prolong the life of the back light and reduce the power consumption. COPYRIGHT: (C)1990,JPO&Japio




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Cited By (12)

    Publication numberPublication dateAssigneeTitle
    EP-0456012-A2November 13, 1991Mitsubishi Denki Kabushiki KaishaAnzeigesteuergerät zur Verminderung des Leistungsverbrauchs
    EP-0494610-A2July 15, 1992Kabushiki Kaisha ToshibaMéthode de commande d'affichage à cristal liquide à transistor à couche mince pour mettre le contrôleur d'affichage en état d'attente quand il n'y a pas d'accès de VRAM
    EP-0496383-A2July 29, 1992Sony CorporationData input and display apparatus
    EP-0498148-A2August 12, 1992Kabushiki Kaisha ToshibaDispositif de commande d'affichage à cristal liquide à transistor à couche mince pour la visualisation de données quand l'accès d'écriture de la mémoire VRAM est détectée
    JP-2012235876-ADecember 06, 2012Heiwa Corp, 株式会社平和遊技機
    US-5247286-ASeptember 21, 1993Mitsubishi Denki Kabushiki KaishaDisplay control device for reducing power consumption of display units
    US-5313225-AMay 17, 1994Asahi Kogaku Kogyo Kabushiki KaishaLiquid crystal display device
    US-5515080-AMay 07, 1996Kabushiki Kaisha ToshibaTFT LCD control method for setting display controller in sleep state when no access to VRAM is made
    US-5926173-AJuly 20, 1999Samsung Electronics Co., Ltd.Circuit for driving liquid crystal display having power saving feature
    US-6310609-B1October 30, 2001Nokia Mobile Phones LimitedUser interface with guide lights
    US-7821489-B2October 26, 2010Panasonic CorporationData processing apparatus
    US-9673365-B2June 06, 2017Osram Opto Semiconductors GmbhOptoelectronic component and electronic device having an optoelectronic component