Accession Number:

AD0744099

Title:

Effects of Turbulence Instabilities on Laser Propagation

Descriptive Note:

Quarterly progress rept. no. 3, 9 Dec 1971-8 Mar 1972

Corporate Author:

RCA LABS PRINCETON NJ

Personal Author(s):

• DE Wolf, David A.

Report Date:

1972-04-01

Pagination or Media Count:

38.0

Abstract:

Several statistics of the focal spot of a focussed laser beam in turbulent air are computed. The average area is recomputed for horizontal propagation, and corrected graphs are presented. Comparison to the half-power area is made, and it is concluded that the irradiance-weighted radius variance is a slightly better criterion, although the differences are small. The calculations are extended to slant paths. The power spectrum of the area scintillation is shown to be proportional to that of angle of arrival of a ray. It is computed for frozen flow and for random flow with zero mean velocity. Both spectra are initially flat, then decay as f to the minus 23 power. A composite formula is suggested for the general case.

Descriptors:

• *COHERENT RADIATION
• *LIGHT TRANSMISSION
• AIR TO SURFACE
• ATMOSPHERIC MOTION
• FOCUSING
• POWER SPECTRA
• SCINTILLATION
• SURFACE TO AIR
• TURBULENCE

Subject Categories:

• Lasers and Masers
• Optics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE