Capacitive proximity sensors

Details Capacitive proximity sensors Capacitive proximity sensors

1992-04-01

1994-08-09

Dwyer, James L.

Telephonic communications

Substation or terminal circuitry

For loudspeaking terminal

379 44, 379424, 379211, 379214, 324660, 34087037, 340562, H04M 100

Patent

active

053373537

ABSTRACT:
Capacitive proximity sensors are disclosed that can be fabricated in different shapes, sizes and materials used in a wide variety of applications. Each such sensor includes a sensing electrode and a guard electrode. The sensor electrode and guard electrode can be parallel conductors separated by an insulating layer, such as a double-sided circuit board shaped to suit the application. One such sensor is transparent for use in conjunction with an optical bar-code scanner. Another sensor is annular in shape for use in conjunction with a telephone transmitter. The sensing electrode and the guard electrode are driven in unison by an RF signal. The proximity of an object to the sensor is observed by detecting changes in the RF current flowing through the sensing electrode caused by the proximity of an object to the sensing electrode.

REFERENCES:
patent: 3250172 (1966-05-01), Tirey
patent: 4650931 (1987-03-01), Tsukada
patent: 4766368 (1988-08-01), Cox
patent: 4893071 (1990-01-01), Miller
Horowitz, P. and Hill, W. "The Art of Electronics", 2nd ed. Cambridge University Press p. 889 (1989).

Affiliated with

Also associated with

Rating

Capacitive proximity sensors does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Capacitive proximity sensors, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Capacitive proximity sensors will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-222183