Abstract: A head gear display system incorporates a simple off-axis optical projection system employing a pair of lenses and an optical combiner for collimating a visual image onto an observer's eye.

Abstract: Apparatus and method for introducing superimposed symbology from a CRT into a dimly lit scene being viewed through a viewing device by utilizing a very small mirror to reflect symbology from the source to the viewing device while minimizing the interference of the reception of light from the dimly lit scene by the viewing device, reducing the light from the source to a level consistent with that from the dimly lit scene and decreasing the aperture from the source so that the symbology remains in focus over a large depth of focus.

Abstract: A wide field of view infrared sensor is disclosed. A field of view in excess of 180 degrees is achieved by the use of a single element, negative miniscus lens. There is provided a flat PbS detector element, and the lens has an anti-reflection coating of SiO.

Abstract: An ultrasonic air movement vector, magnitude and temperature sensing apparatus using a three element ultrasonic probe with a common transmitter element sending wave energy to selectively positioned receiving elements in the probe in combination with an electronic computational circuit to produce air movement and temperature indicative signals.

Abstract: Apparatus including discrimination circuitry for reliably identifying a target illuminated by a pulsed laser beam is disclosed. Laser energy received from objects within a field of view is imaged on one or more elements of an optical detector which produces electrical signals indicative of the direction of arrival of the laser energy. Signals from the detector are selectively passed to a display device by means of self-adaptive gating circuitry which blocks signals occuring during intervals when valid signals are not expected. Means for discriminating as to optical frequency, and for utilizing only the last returned reflection of each transmitted laser pulse is also disclosed for further increasing reliability.