Hughes Aircraft Company

Hughes Aircraft

William A Smith

August H Beining

Gary M Sach

Eugene L Brodie

Larry A Dial

Francisco Palop

Gene W Rieck

A tactile feedback switch actuator for an associated force-actuated switch has a key cap linked to a collapsible dome by an optical fiber, all of which are light-transmittable. The actuator is operated by manually applying an actuating force to the key cap which exceeds the modulus of collapse of the dome. In response, the dome reversibly collapses in a tactile snapping action against the underlying light-transmittable switch panel having pressure-sensitive contacts embedded therein to change the operative state of the switch. When the actuating force is withdrawn, the collapsible dome elastically returns to its uncollapsed condition, while the switch remains in its newly-actuated operative state. The actuator and associated switch are structurally integrated and aligned so that light-emitting pixels in an underlying electroluminescent panel provide visual feedback of the operative state of the switch.

Tactile feedback switch actuator

A printed wiring board carries electronic components. A castable body is of thermally conductive dielectric material and is molded from the printed wiring board to the exact configuration of the electronic devices. A metal plate completes the conductive converter, which includes the castable body. The conductive converter can be clamped to a cold plate and a card box to conductively remove heat from the electronic components. The molding process may be direct molding of the castable body onto the electronic device side of the printed wiring board or may include indirect steps. Protection of the electronic devices and printed wiring board and filling of the undercuts may be accomplished by vacuum-forming an electrically conductive polymer sheet over the devices during molding followed by removing of the sheet when the thermal mounting plate is attached.

Circuit card assembly conduction converter

The thermal mounting plate has a pocket therein which contains dielectric elastomer. The pins on the pin side of the circuit card assembly engage in the elastomer to conduct heat from the components through the pins and elastomer into the thermal mounting plate. The thermal mounting plate mounts into a cooled card box for heat removal.

An electromagnetic energy interference seal arrangement is provided for use in light beam touch panel systems. The electromagnetic energy interference seal includes the use of waveguides associated with the light beam sources and detectors to improve light beam touch panel performance. The waveguide size is selected so that it operates as a waveguide above cutoff frequency for the light beams but operates as a waveguide below cutoff frequency for blocking electromagnetic energy interference. The waveguides improve the light beam signal to noise ratio since they shade the detectors from reflections and from extraneous light such as from overhead room lighting. Bonding of part of the electromagnetic energy interference seal is effected by an electrically conductive compound which enables nondestructive disassembly when required. Environmental sealing strips are provided to cover the waveguide apertures to protect against dust, liquids and other environmental contaminants.

Electromagnetic energy interference seal for light beam touch panels

A touch panel system for displays is provided having electromagnetic energy interference shielding arrangements coupled with other features for an integrated, easily maintained, operator-adapted touch panel system. The system includes an electromagnetic energy interference shielding bezel mounted at the front of the display unit to an outer display housing. The bezel is integrated with an optically transparent and electrically conductive faceplate covering the display, and a raised border with an associated electromagnetic energy interference seal located at the periphery of the active touch panel area which is disposed between the faceplate and the bezel to complete an electrical path. The faceplate is roughened to disperse spatial interference patterns and reflections, and in one embodiment, has an electrically conductive wire mesh disposed within it for electromagnetic energy interference sealing and contrast enhancement for filtering extraneous light in the manner of a venetian blind. The faceplate may be provided with an electrically conductive coating for electromagnetic energy interference shielding and for contrast enhancement. The system includes a fixed function key area around the periphery of the display screen within the active touch panel area as defined by the raised border/zeal combination. The raised border/seal combination can be slanted to eliminate undesired reflection of the edge light beams.

Growing community of inventors

Laguna Hills, CA, United States of America

William A Smith