Liquid crystal display system with variable backlighting for data processing machine

• US 5,144,292 A
• Filed: 07/17/1986
• Issued: 09/01/1992
• Est. Priority Date: 07/17/1985
• Status: Expired due to Term

• Current Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Kawano, Isao, Shiraishi, Tomikatsu
• Primary Examiner(s): Oberley, Alvin E.
• Application Number:
  US06/886,423
• Time in Patent Office: 2,238 Days
• Field of Search: 340/784, 340/765, 340/793, 340/716, 350/345, 359/48
• US Class Current: 345/102
• CPC Class Codes: G09G 2320/0606 Manual adjustment
• CPC Class Codes: G09G 2320/0626 for control of overall brightness
• CPC Class Codes: G09G 2320/0633 by amplitude modulation of the brightness of the illumination source
• CPC Class Codes: G09G 3/30 using electroluminescent panels
• CPC Class Codes: G09G 3/3406 Control of illumination source illumination devices structurally associated with liquid crystal cells G02F1/1336

Abstract

A data processing device is provided with a liquid crystal display incorporating electroluminescent backlighting, in which the electroluminescent backlighting panel is provided with several degrees of luminosity. A selection circuit specifies the degree of luminosity to allow the electroluminescent backlighting panel to generate the selected luminosity level.

Claims

1. A data processing machine, comprising:

memory means for storing control instructions and data;

processing means for executing said control instructions and processing said data;

liquid crystal display means for displaying data, including an electroluminscent backlighting panel;

means for driving said electroluminescent backlighting panel at several levels of luminosity; and

means for selecting a specific level of luminosity to cause said driving means to drive said electroluminescent backlighting panel at said specific level;

said means for selecting including a data latch circuit which outputs a specific luminosity level code to said means for driving.

2. The data processing machine as claimed in claim 1, wherein said several levels of luminosity comprise a plurality of discrete values.

3. The data processing machine as claimed in claim 1, wherein said several levels comprise at least two discrete values.

4. The data processing machine as claimed in claim 3, wherein said several levels comprise four levels.

5. The data processing machine as claimed in claim 1, wherein said means for selecting comprises a keyboard.