A Dual Electro-Optical Light Image Receiver and Recorder.
Abstract
A novel optical experiment is underway at the Air Force Geophysics Laboratories to measure rotation and translation of the earth's crust. The purpose of the experiment is to improve azimuth monitoring. The primary reference is a laser beam. The beam is optically split and aimed at two optical reflectors mounted on a common base in the earth's crust and normal to the horizontal. The reflected beam from reflector, a plane, mirror, is a measure of vertical and horizontal rotation. The reflected beam from the second reflector, a corner cube, is a measure of vertical and horizontal translation. The Dual Electro-Optical Biaxial Sensor described in this report is designed to sense the movement of the laser beams and record the results on an Incremental Magnetic Recorder. The specification to measure position of each of the two reflected beams over a dynamic range of 12 millimeters with a resolution of 0.01mm even with a large incident spot size, 20mm, is met by employing a large biaxial Schottky barrier photodiode. The excellent repeatability of this electro-optical position detector permits calibration of non-linearity with post experiment computation to reduce error in measurement to 0.01mm.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1977
- Accession Number
- ADA037955
Entities
People
- Edward P. Morse