Preventing noise in a coordinate input device by reducing or sus

Details Preventing noise in a coordinate input device by reducing or sus Preventing noise in a coordinate input device by reducing or sus

1997-05-27

1999-04-20

Zimmerman, Mark K.

Computer graphics processing and selective visual display system

Plural physical display element control system

Display elements arranged in matrix

345183, 345210, 345211, 345212, 345213, G09G 302

Patent

active

058961208

ABSTRACT:
A d.c. voltage is supplied to an inverter power source to drive a light source. Light from the light source is directed uniformly from the back side of a liquid crystal panel. When an image is displayed on the liquid crystal panel during a display period and a position detection pen is in close proximity to the liquid crystal panel at a position detection period, coordinates are calculated according to an induced voltage by the position detection pen and the timing of applying a scanning voltage to an electrode of the liquid crystal panel. The driving of the light source by the inverter power source is suspended or reduced during the position detection period, so that noise from the inverter power source is prevented from being mixed into the position detection pen.

REFERENCES:
patent: 3886311 (1975-05-01), Rodgers et al.
patent: 4131864 (1978-12-01), Kuzumoto et al.
patent: 4865425 (1989-09-01), Kobayashi et al.
patent: 4988837 (1991-01-01), Murakami et al.
patent: 5144203 (1992-09-01), Fujita et al.
patent: 5187655 (1993-02-01), Post et al.
patent: 5357266 (1994-10-01), Tagawa
patent: 5386219 (1995-01-01), Greanias et al.
patent: 5410329 (1995-04-01), Tagawa et al.
patent: 5430462 (1995-07-01), Katagiri et al.
patent: 5442373 (1995-08-01), Nomura et al.
patent: 5448024 (1995-09-01), Kawaguchi et al.
patent: 5491706 (1996-02-01), Tagawa et al.
patent: 5495263 (1996-02-01), Dalton et al.

Affiliated with

Also associated with

Rating

Preventing noise in a coordinate input device by reducing or sus does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Preventing noise in a coordinate input device by reducing or sus, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Preventing noise in a coordinate input device by reducing or sus will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2250888