SPATIAL MODULATION OF LIGHT BY OPTICAL PUMPING.
Abstract
A study was made to determine the feasibility of spatially-modulating a coherent light beam with an incoherent light image I sub ic. This technique is based on the principle that I sub ic can pump atoms into a metastable energy level that can partially absorb coherent light of the proper frequency. Three- and four-level atomic systems were considered, with the latter found to be more suitable. Formulae were derived for the modulation, response time, and signal-to-noise ratio of the four-level system. A numerical example is given to demonstrate its feasibility. A useable range of level decay rates and energies is tabulated to facilitate the search for an appropriate modulating material. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 15, 1967
- Accession Number
- AD0823507
Entities
People
- Robert Lehmberg
Organizations
- Naval Air Warfare Center Warminster