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Optical distance measuring instrument
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Copyright Year | 1986 |
| Description | An optical instrument, such as a stability monitor or a target range finder, uses an unstabilized laser to project a composite optical signal of coherent light having two naturally occurring longitudinal mode components. A beamsplitter divides the signal into a reference beam which is directed toward one photodetector and a transmitted beam which illuminates and is reflected from a distant target onto a second photodetector optically isolated from the first photodetector. Both photodetectors are operated on the square law principle to provide electrical signals modulated at a frequency equal to the separation between the frequencies of the two longitudinal mode components of the optical signal projected by the laser. Slight movement of the target may be detected and measured by electrically monitoring the phase difference between the two signals provided by the photodetectors and the range of the target measured with the aid of a microprocessor by changing the separation between the longitudinal modes by shifting the length of the resonator cavity in an iterative series of increments. |
| File Size | 800291 |
| Page Count | 9 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_19860022794 |
| Archival Resource Key | ark:/13960/t2f817k9c |
| Language | English |
| Publisher Date | 1986-07-15 |
| Access Restriction | Open |
| Subject Keyword | Optics Stability Microprocessors Photometers Monitors Targets Laser Applications Range Finders Optical Measuring Instruments Beam Splitters Coherent Light Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Patent |
