Long Wavelength Modulation Techniques (10.6 microns).
Abstract
This program was an exploratory study, consisting of theoretical and experimental analyses, whose principal goal was to identify an optimum modulation technique for intensity modulation of a 10.6 micrometer CO2 laser. Performance requirements were minimum frequency response of 200 MHz and modulation depth approaching 100% with minimum driver power. A comprehensive review of all know applicable modulation techniques was undertaken. This included the electro-optic effect, Stark effect, acousto-optic effect, and free carrier related effects. Novel, innovative techniques were also explored. By a two-stage elimination process, techniques having inherent frequency response limitations well below 200 MHz, and techniques having extreme or catastrophic power burdens were identified and eliminated. The surviving candidate techniques or structures, all based on the electrooptic effect, were determined to be, in order of descending figure of merit: (1) optical waveguide, (2) intracavity coupling, (3) microwave passband traveling wave, (4) baseband, parallel strip TEM traveling wave, and (5) multiple pass, lumped element. Considerable experimental work on intracavity coupling modulation was undertaken, partially supported under this program, with demonstration of flat frequency response well beyond 500 MHz.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1973
- Accession Number
- AD0907615
Entities
People
- A. E. Popa
- J. E. Kiefer
- J. F. Lotspeich
Organizations
- HRL Laboratories