Browse Prior Art Database

Automatic Backlight Adjustment and Battery Usage Extender for Liquid Crystal Display Panels

IP.com Disclosure Number: IPCOM000113970D
Original Publication Date: 1994-Oct-01
Included in the Prior Art Database: 2005-Mar-27
Document File: 2 page(s) / 32K

Publishing Venue

IBM

Related People

Gladstein, L: AUTHOR [+3]

Abstract

Described is a hardware implementation to provide automatic adjustment to the backlighting of Liquid Crystal Display (LCD) panels and to extend the life of batteries which drive the LCDs. The implementation involves a micro-controller and associated circuitry and software to provide automatic adjustment of the LCD backlighting without user intervention. The micro-controller may be the same one as used for other system functions.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 100% of the total text.

Automatic Backlight Adjustment and Battery Usage Extender for Liquid
Crystal Display Panels

      Described is a hardware implementation to provide automatic
adjustment to the backlighting of Liquid Crystal Display (LCD) panels
and to extend the life of batteries which drive the LCDs.  The
implementation involves a micro-controller and associated circuitry
and software to provide automatic adjustment of the LCD backlighting
without user intervention.  The micro-controller may be the same one
as used for other system functions.

      The Figure shows a block diagram of the circuitry used to
provide the automatic backlight adjustment for LCD panels.  The
ambient light is monitored at the photo cell and through the series
of control elements, as shown.

      The circuitry automatically adjusts the backlighting intensity
when voltage is applied to the backlight section of the LCD panel.
As the backlighting intensity decreases, battery power consumption
also decreases, thereby extending the life of the battery.