Optical detection apparatus is provided which includes a coherent light sce for generating a beam of coherent light. The apparatus further includes a unitized or discrete optical component which receives the generated beam, and projects light thereof which has a particular polarization characteristic into a specified environment. The optical component also functions to receive or absorb light from the environment which has the particular polarization characteristic, and to directably reflect light from the environment which does not have the polarization characteristic. A lens or other light collecting device focuses light reflected by the discrete optical component upon a light detection element. A light conducting path is provided between the coherent light source and the light detecting element to enable generated coherent light to be mixed with the reflected light upon the light detecting element to provide data signals which indicate the presence of an object in the environment.
A laser rangefinder apparatus is provided which includes a laser transmitter for transmitting a coherent light pulse over an optical path to a target. The light pulse is reflected from the target as a reflected pulse and travels back to the laser rangefinder over the same optical path. The reflected light pulse is provided to a fiber optic interface module which supplies the pulse to a fiber optic interface cable. The fiber optic interface cable supplies the reflected pulse to a laser receiver. The laser receiver includes a signal processor which performs the distance to target calculation and displays the resultant distance to the user. The fiber optic interface module and fiber optic interface cable permit great flexibility in the placement of the laser receiver with respect to the laser transmitter of the rangefinder.
A variable attenuator for optical transceivers such as laser rangefinders for ordnance control. A polarization rotation device, such as a mechanically rotatable half-wave plate or an electrooptic cell, operates in combination with a beam splitter polarizer to attenuate the transmitted laser beam by a continuously variable amount without further attenuating the received laser beam.
An optical radar system includes an optical transmitter which responds to a drive signal to radiate a search light pulse into detection fields arranged in the direction in which the vehicle is moving. An optical receiver includes a plurality of arrayed photoelectric sensitive elements which receive any search light pulses reflected by objects in the detection fields. A distance measuring device determines the respective distances from the system to the objects and the corresponding directions in which the objects lie in accordance with the delay between the drive signal and the reception of the corresponding reflected search light pulses by the individual photoelectric elements.
A laser radar system having amplification of the optical beam. In a system where it is desired to achieve greater information content or greater system sensitivity, one or more laser amplifiers in the beam paths provide greater optical power for increased distance. Eleven system architectures are disclosed for use with a modified Mach-Zehnder interferometer, eleven are disclosed for use with a Fizeau interferometer, and three are disclosed for use in a noncoherent optical system. The embodiments are distinguished by the number and placement of the laser amplifiers in the optical paths of the system.
The disclosed apparatus is a temperature tracking narrow band optical range finder which includes a prior art GaAs laser diode for emitting a laser energy pulse to a target and an improved GaAs avalanche detector for receiving a reflected pulse from the target. This range finder can be arranged in a single optical axis with the laser diode electrically shielded from the detector and the reflected pulse defocused so as to impinge on the detector area surrounding the laser diode, or it can be arranged by combining the emitted and reflected pulse in an interspersed fiber optical plane.
