Bell Telephone Laboratories

Rca Inc.

Ralph H Storz

Gary C Bjorklund

Gary Carl Bjorklund

Richard R Freeman

John Castleberry, Jr

Christopher P Ausschnitt

Edward Peter Cecelski

An apparatus is disclosed for servo-locking the angular orientation of a nonlinear crystal to the angle at which phasematching occurs for nonlinear optical frequency mixing processes. Two secondary beams are generated from a beam of radiation which is incident upon the crystal. They travel through the crystal at small angles with respect to the main beam and each generates a secondary output beam containing new frequency components produced by the nonlinear optical frequency mixing process in the crystal. A discrimination signal is created by subtracting the generated power at the new frequency component of one of the secondary output beams from the generated power of the other. This signal is sensitive to the angular misalignment of the crystal and is used to drive a servo system to maintain the proper angular orientation for phasematching.

Servo-control alignment of nonlinear crystals

Atoms of hydrogen or deuterium are fully ionized by a three-photon process which is enhanced by the two-photon 1S.fwdarw.2S resonant transition. The resultant ions are detected with high efficiency to provide discrimination between small concentrations of atomic hydrogen and atomic deuterium in a vacuum or in the presence of a background gas. The use of two unequal photo energies to pump the two-photon resonance provides the capability of mapping the individual three dimensional distribution of the hydrogen or deuterium. The detection process is also appropriate to determining these data in dishcarge plasmas and flames.

Detection of ground state hydrogen and deuterium

A receiver of ultrasonic pulses having a known pulse width and at a known spacing includes a gate which is normally conditioned to accept the ultrasonic pulses. When the first pulse is received, however, the gate is opened thereafter only when subsequent pulses should be present and is closed when no pulses are expected. Such an arrangement prevents multipath signals being interpreted by the receiver as information.

Ultrasonic digital receiver

Growing community of inventors

Freehold, NJ, United States of America

Ralph H Storz