Electricity: circuit makers and breakers – Electric switch details – Indicators
Patent
1998-07-08
1999-10-05
Luebke, Renee S.
Electricity: circuit makers and breakers
Electric switch details
Indicators
362 85, 362800, H01H 918
Patent
active
059609427
ABSTRACT:
A backlit keypad assembly includes a flexible film having a bottom surface having electrical circuits, typically referred to as flex circuits, thereon and a top surface having at least one, and preferably a plurality of keys defined thereon. Each backlit key includes a cavity on the underside thereof. In each cavity is a light emitting diode, preferably of bottom emitting type, attached to the flexible film and connected to the electrical circuits and a filler material which at least partially surrounds the light emitting diode. Associated with each key is a push-type switch below and in respective aligned relationship with the light emitting diodes which senses when the corresponding key is pressed down by a user. The light emitting diodes emit light directly through the flexible film without intervening layers such as light guides, thereby allowing the overall lighted keypad assembly to be thinner than with previous approaches. Such a keypad may be fabricated by directly attaching a plurality of bottom emitting light emitting diodes to the bottom side of the flexible film and connecting the light emitting diodes to the electrical circuits. Thereafter, the flexible film is vacuum formed so as to form a plurality of depressible keys on the top surface thereof and a corresponding plurality of cavities on the bottom surface thereof containing therein the light emitting diodes. The process continues by thereafter substantially filling the remainder of the cavities with a filler material which hardens upon curing and adheres to the bottom surface of the flexible film so as to form a flexible pad. The flexible pad is then typically placed in intimate contact with the printed circuit board and preferably mated thereto.
REFERENCES:
patent: 4385213 (1983-05-01), Larson
patent: 4975814 (1990-12-01), Schairer
patent: 5097396 (1992-03-01), Myers
patent: 5149923 (1992-09-01), Demeo
patent: 5847336 (1998-12-01), Thornton
Ericsson Inc.
Luebke Renee S.
LandOfFree
Thin profile keypad with integrated LEDs does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Thin profile keypad with integrated LEDs, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Thin profile keypad with integrated LEDs will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1161277