Abstract: A scanner and a method for scanning a beam along a path employs a housing tint defines a first cylindrical cavity. A ring gear is disposed within the cylindrical cavity and affixed to the housing. A beam is generated from a fixed location relative to the housing. A drive disk is disposed within the first cylindrical cavity. The drive disk defines a second cylindrical cavity and has a first axis of rotation. The drive disk defines a first channel in communication with the beam. The first channel has a first proximal end pivotally rotatable about an axis adjacent the fixed location. A scan disk is disposed within the second cylindrical cavity and has a second axis of rotation offset from the first axis of rotation. The scan disk defines a second channel. The second channel has a second proximal end in communication with the first distal opening. The second proximal end pivotally rotates about an axis adjacent the first distal end.

Abstract: An acousto-optic apparatus is described that varies the time delay of electrical signals over a continuum of delays. In the preferred embodiment, a light source, which can be either coherent or incoherent, emits an optical beam that is focused into an acousto-optic cell. An input electrical signal is used to drive the acousto-optic cell which, in turn, modulates the focused optical beam. Portions of the input optical beam are modulated and diffracted at angles proportional to the frequencies and phases contained in the input electrical signal. By appropriately choosing the cone of angles at which the light is focused into the acousto-optic cell, the diffracted optical beam can be made to overlap with portions of the undiffracted, unmodulated optical beam. All of the light exiting the acousto-optic cell is then collected onto a device for detection. Optical photomixing of the diffracted beam and the undiffracted beam is performed in order to derive the input electrical signal with a time delay.

Abstract: An acousto-optic correlator for wideband signals. The invention is defined by and relates to device in which a laser beam is split into two paths of a Mach-Zehnder interferometer arrangement. A first Bragg cell of which, modulated with a signal Re{S.sub.1 (t)exp(jw.sub.o t)}, receives the first beam that is reflected off a first flat mirror. A second Bragg cell of which, modulated with a signal Re{S.sub.2 (t)exp(jw.sub.o t)}, receives a beam that is reflected off a second flat mirror. The undiffracted light from both of the modulators is blocked. The diffracted light emitted from the first and second Bragg cells passes through first and second imaging lenses respectively. The two diffracted light beams are then combined with an angular separation between beams. The combined beam is incident upon a square-law detector array which is at the image plane of the imaging lenses. Due to the square-law detection process, terms of low frequency biases and complex correlation on a spatial carrier develop.