Blue/Green Coupled Wave Filter Study.
Abstract
High-resolution measurements of AgGaS2 iso-index electrooptic filter samples have confirmed earlier theoretical predictions. We observed a filter passband of less than 1.0 A at 4970 A in a sample 3 mm thick and have achieved electrooptic control of transmission efficiency up to a maximum of 60% with about 1000 V. These results translate to filter passbands of less than 0.3 A in a 1-cm sample with comparable voltage requirements and with negligible electric power dissipation. The filter response for off-normal light beams indicates an FOV capability in excess of 60 half-angle (f/0.3) with less than a 20% increase in passband over that of the narrow-field condition. Fine tuning of the pass wavelength by temperature variation showed a tuning rate of 0.25 A/C. Theoretical characterization of iso-index materials demonstrated that crystals with large nonresonant birefringence and small fundamental bandgap shifts yield narrow passbands. A useful figure of merit for predicting filter performance was derived. Potentially useful materials include the II-VI mixed crystal semiconductors (CdS-ZnO) and the mixed ternary chalcopyrites (AgGaS2-CuAlS2). (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1980
- Accession Number
- ADA079805
Entities
People
- D. M. Henderson
- J. F. Lotspeich
Organizations
- HRL Laboratories