Abstract

This paper concerns the use of pulsed light sources of extreme luminance and short duration in measuring the transmissivity of the air along a slant path; the glide approach path to an airport runway is of particular interest. The fundamental pulsed-light-transmissometer technique is described for an idealized atmosphere and an idealized single-ended transmissometer (confocal transmitter and receiver). Complications arising for real conditions are avoided by the following modified technique: A transmitter on the ground projects a series of light pulses up the glide path, during which time a receiving system separated to the side collects light scattered from the transmitter beam at each of a sequence of predetermined ranges and plots the scattered light flux received against time. These return plots are graphically superimposed on a single time base and an envelope of the return peaks is drawn. Equations representing individual returns indicate that their peak envelope can be used to determine the transmissivity at any given range and the average transmissivity over a given path.

Signal variations due to clouds and absorbing media are discussed, and the use of the technique in a ceilometer is mentioned. Path length limitations due to equipment features and to secondary scatter under low-transmissivity conditions are discussed. Measurements obtained with an experimental pulsed-light transmissometer are given and compared with measurements by two other systems.

© 1961 Optical Society of America

Full Article  |  PDF Article
OSA Recommended Articles
Atmospheric Light Transmission in a Wisconsin Area

Israel Cantor and Andrew Petriw
Appl. Opt. 7(7) 1365-1381 (1968)

The Measurement of Light Scattered by the Upper Atmosphere from a Search-Light Beam

E. A. Johnson, R. C. Meyer, R. E. Hopkins, and W. H. Mock
J. Opt. Soc. Am. 29(12) 512-517 (1939)

Infrared Measurements of Atmospheric Transmission at Sea Level

John L. Streete
Appl. Opt. 7(8) 1545-1549 (1968)

References

You do not have subscription access to this journal. Citation lists with outbound citation links are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Cited By

You do not have subscription access to this journal. Cited by links are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Figures (20)

You do not have subscription access to this journal. Figure files are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Equations (15)

You do not have subscription access to this journal. Equations are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription