422.7-nm atomic filter with superior solar background rejection.
A novel atomic resonance filter with powerful solar background rejection is proposed. The filter wavelength matches the g Fraunhofer line at 422.7 nm. Atomic filtering occurs within the singlet manifold of neutral calcium. Superior sunlight discrimination arises mainly from two factors: overlay with an intense Fraunhofer line and signal levels devoid of fine and hyperfine structures. The new filter should exhibit high throughput and low noise.
Gelbwachs
J A
JA
Chemistry and Physics Laboratory, The Aerospace Corporation, M2/253, P.O. Box 92957, Los Angeles, California 90009, USA.