Lucien M. Biberman

Infrared Continuum Absorption by Atmospheric Water Vapor in the 8-12- Micrometer Window

We have carried out a detailed analysis of several long pathlength transmission measurements in the 8-12-microm atmospheric window in order to determine the extinction coefficient due to the water vapor continuum. Our results indicate that three modifications to the current LOWTRAN atmospheric transmission model are required. The first two corrections involve an improved fit to the pure water vapor continuum absorption together with the elimination of the atmospheric broadened continuum term. Finally, and most critically, a strong measured temperature dependence must be included in the water vapor continuum absorption coefficient. For pathlengths ranging from 10 km to 50 km, failure to incorporate these corrections can lead to errors in the computed transmission ranging from factors of 2 to more than 10,000.

INFRARED TARGET AND BACKGROUND RADIOMETRIC MEASUREMENTS-CONCEPTS, UNITS, AND TECHNIQUES

Abstract This report discusses concepts units and techniques for making and describing measurements of radiation from targets and backgrounds.

Background Considerations in Infrared System Design

The problem of locating a radiant target against a cluttered background is discussed. The form of sky clutter and its representation are considered in a limited way, and two criteria for recognizing a radiant source against a background are put forward.

Omphaloskepsis on Current Trends in Optics

The laser opened two wide new channels for optics, one concerning development of more and better lasers, one concerning the laser as tools for new research and as components for new techniques. Two trends, one resulting from each channel, are examined. The reaction of the physics community to the importance of these events is pointed up by the recent APS-NYS meeting, which is reviewed briefly.