Evaluation of Technologies for Infrared Imaging.
Abstract
This report assesses the practical value of a new technique of upconverting infrared radiation using two-photon pumped alkali metal vapors and compares the relative merits of several approaches to IR imaging. Performance criteria of passive and active IR imaging systems are chosen and practical configurations are defined. The principles of IR upconversion using alkali metal vapors and the infrared quantum counter are detailed. The upconversion efficiency, acceptance angle and IR bandwidth are evaluated. Upconversion with nonlinear crystals and direct detection of IR are also briefly treated. Detailed and practical systems are designed for passive and active imaging based on the several approaches and the performance indicators are evaluated. The upconversion methods in their present stage of development are not found to perform as well as the state-of-the-art direct-detection methods. The infrared quantum counter (IRQC) is at present the best upconversion candidate for thermal imaging because of its ability to integrate the thermal radiation. Upconversion in sodium vapor is promising in both the passive and active cases approaching, in the latter, the performance of direct detection. The IRQC does not appear to have any merit for active imaging. The performance of nonlinear crystal upconverters is significantly poorer than the metal-vapor upconverters.(Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 01, 1976
- Accession Number
- ADA036211
Entities
People
- John S. Ostrem
- Kamala S. Krishnan
Organizations
- SRI International