Abstract: An ultrasonic transducer having a unique design that can withstand changes in temperature and pressure and will operate in corrosive environments. The transducer is used to detect the distance to an object being measured. The device includes a diaphragm from which is emitted a focused ultrasonic wave. The diaphragm and a capsule housing are machined from a single piece of metal and does not use adhesives or welded joints. The capsule housing is also filled with silicone oil and provided with a flexible annular ridge, both of which enhance its operation and improve signal transfer. A crystal centering seal extends 75%-90% the thickness of the crystal. A method for creating a negative internal pressure provides for improved ultrasonic wave propagation.
Abstract: The present invention provides a laser radar (ladar) imaging system in which both the range of an object being imaged and the velocity of the object can be measured simultaneously and accurately with superior range resolution and with minimal ambiguity. Use is made of a ladar system based on matched-filter cross-correlation of light pulse waveforms that have multiple, simultaneous frequency components with phase variation and incommensurate spectral frequency spacing between frequency components.
Type:
Grant
Filed:
May 17, 1996
Date of Patent:
November 10, 1998
Assignee:
Coherent Technologies
Inventors:
Mark W. Phillips, Paul J. M. Suni, J. Alex L. Thomson