Abstract

When a slightly divergent laser beam passes through a turbulent ground level atmosphere and strikes a linear grating, fluctuating self-images are formed at Talbot distances. By superimposing a similar grating on one of the self-images, even for the case of parallel gratings’ lines, fluctuating moiré fringes are formed owing to the beam divergence. Recording the successive moiré patterns by a CCD camera and feeding them to a computer, after filtering the higher spatial frequencies, produces highly magnified fluctuations of the laser beam. Using moiré fringe fluctuations we have calculated the fluctuations of the angle of arrival and the atmospheric refractive index structure constant. The implementation of the technique is straightforward, a telescope is not required, fluctuations can be magnified more than ten times, and the precision of the technique is similar to that reported in our previous work.

© 2008 Optical Society of America

Application of moiré technique to the measurement of the atmospheric turbulence parameters related to the angle of arrival fluctuations

Saifollah Rasouli and M. Taghi Tavassoly
Opt. Lett. 31(22) 3276-3278 (2006)

Use of a moiré deflectometer on a telescope for atmospheric turbulence measurements

Saifollah Rasouli
Opt. Lett. 35(9) 1470-1472 (2010)

Angle-of-arrival fluctuations of a reflected beam in atmospheric turbulence

James H. Churnside and Richard J. Lataitis
J. Opt. Soc. Am. A 4(7) 1264-1272 (1987)

Application of “parallel” moiré deflectometry and the single beam Z-scan technique in the measurement of the nonlinear refractive index

Saifollah Rasouli, H. Ghasemi, M. T. Tavassoly, and H. R. Khalesifard
Appl. Opt. 50(16) 2356-2360 (2011)

An adjustable, high sensitivity, wide dynamic range two channel wave-front sensor based on moiré deflectometry

Saifollah Rasouli, M. Dashti, and Anamparambu. N. Ramaprakash
Opt. Express 18(23) 23906-23915 (2010)