Abstract: The use of spatial light modulators to steer light beams is disclosed. A dual frequency liquid crystal spatial light modulator can be controlled so as to form a blazed phase grating thereon that effects desire deflection of incident light.

Abstract: The use of spatial light modulators to steer light beams is disclosed. A dual frequency liquid crystal spatial light modulator can be controlled so as to form a blazed phase grating thereon that effects desire deflection of incident light.

Abstract: The use of spatial light modulators to steer light beams is disclosed. A dual frequency liquid crystal spatial light modulator can be controlled so as to form a blazed phase grating thereon that effects desire deflection of incident light.

Abstract: A method and system for aligning a spatial light modulator with respect to an imaging device is disclosed. An image of the spatial light modulator can be formed upon the imaging device and a controller can be used to position optical elements in a manner that effects translation, rotation, and scaling of the image so as to provide desired alignment. Such alignment can, for example, facilitate enhanced wavefront correction so as to at least partially compensate for the detrimental effects of atmospheric distortion in such applications as optical communications, imaging, and weaponry.

Abstract: A method and system for aligning a spatial light modulator with respect to an imaging device is disclosed. An image of the spatial light modulator can be formed upon the imaging device and a controller can be used to position optical elements in a manner that effects translation, rotation, and scaling of the image so as to provide desired alignment. Such alignment can, for example, facilitate enhanced wavefront correction so as to at least partially compensate for the detrimental effects of atmospheric distortion in such applications as optical communications, imaging, and weaponry.

Abstract: A method for detecting, locating and measuring leaks in a test object is described using a differential absorption technique. In a preferred embodiment the test object is first pressurized with a light absorbing fluid. The test object is then illuminated with a light source at a wavelength which is capable of being absorbed by the absorbing fluid. An image of the test object and any fluid in the vicinity of the test object is created by means of a video camera directed toward the test object and that image is electronically stored. A second image is then created in such a manner that any absorbing fluid in the vicinity of the test object does not appear in that second image. The second image is also electronically stored. The electronically stored information regarding the first and second images are then compared and analyzed for detecting, locating and measuring any leaking fluid from the test object.

Abstract: A method and apparatus for real-time determination of weld quality. A collimated light source 10 directs a beam 16 of collimated light to a point on the weld pool surface 24. A position sensor 34 measures the direction of the light after it is specularly reflected from the weld pool surface 24. Electronic means 36,38,40 analyze this measurement for determining changes in angles of the weld pool surface 24 for real-time indication of the state of penetration of the weld pool 26.

Abstract: An optical pressure sensor 10 for measuring the pressure within a container 12 such as a combustion chamber of a rocket engine, wherein pressure sensor 10 comprises a pressure deflectable diaphragm 14 in communication with container 12 and which includes an optical grating 22 on one of its surfaces, means 18 for directing a laser 20 to strike optical grating 22 from a fixed direction to form a central diffracted beam 24 and a first order diffracted beam 26, a photo-position detector 60 for generating signals responsive to the changes in position of the central and first order diffracted beams 24 and 26 resulting from the effects of pressure and temperature upon the diaphragm 14, and means 30 for synthesizing a temperature-adjusted indication of the pressure in the subject container from said responsive signals.