Ambient light ad electromagnetic noise reduction circuit

Details Ambient light ad electromagnetic noise reduction circuit Ambient light ad electromagnetic noise reduction circuit

G - Physics

08

B

340/72

G08B 1/08 (2006.01) G06F 3/033 (2006.01)

Patent

CA 1220829

ABSTRACT OF THE DISCLOSURE A circuit for reducing noise and increasing the reliability of touch panels involves the use of a supplemental noise or electromagnetic interference pickup lead (63) which extends generally coextensively with the parallel connected outputs from a series of successively coupled photodetectors (42) and high pass filters (49, 58, and 60 and 64, 65 and 66) for substantially reducing the noise signals created by variations in the level of ambient light, When the photodetectors output (46) is connected to one of the inputs (-) of a differential operational amplifier (56), and the com- pensating pickup lead (63) is connected to the opposite polarity other input (+), the noise is substantially can- celled out, and a cleaned-up photodetector pulse is provided. A pulse forming circuit (74, 75 and 77) squares up the photodetector output signal pulse; and a hysteresis type storage or buffer circuit (76 and 78) is employed to indicate the presence or absence of photodetector output signals, from successive photodetectors, thereby indica- ting whether or not the light beams are interrupted either fully or partially.

458555

Affiliated with

Also associated with

Rating

Ambient light ad electromagnetic noise reduction circuit does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Ambient light ad electromagnetic noise reduction circuit, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Ambient light ad electromagnetic noise reduction circuit will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFCA-PAI-O-1272012