Infrared coherent optical sensor
USH933H · kind H · statutory invention registration
Assignee
Inventors
Key dates
| Filing date | — |
| Grant date | Jul 2, 1991 |
| Priority date | — |
| Expiry date | — |
Classification
- Technology area (CPC —)General
Abstract
A dual-beam amplitude-modulated laser transmitter/receiver suitable for laser-radar applications is scalable to high powers because there is no active modulator element that the laser beam passes through. The transceiver comprises a laser source with two separate independent laser optical cavities. Each laser cavity is similar, but each operates at its own frequency. Signals from the two cavities are superimposed at a combining beam splitter to form two transmitter output beams with each combined beam intensity modulated at the laser difference frequency. The output consists of two beams separated in elevation and with equal beam powers from each laser cavity the intensity modulation is 100%. Each beam has its own homodyne detector and separate local oscillator. Thus, each beam path is considered to be a distinct homodyne transceiver. If the frequency of one of the laser sources is changed in time, an AM/FM/CW output suitable for absolute range measurements and fine doppler is generated. The laser transmitter does not require internal or external modulators such as acousto-optic or electro-optic cells. Thus, it is not limited by the modulator characteristics.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.