Abstract
Theoretical analysis and computer simulation show that it is possible to measure accurately the second moment of image irradiance distributions with considerable undersampling. The measurement error is found by applying the moment theorem to the sampled distributions. Sampling with small elements is compared to sampling with extended elements, and it is shown that the latter is always more accurate. Error calculations for a Gaussian beam and for a square aperture are presented. For a Gaussian the sampling interval can be as large as 2.3sigma (sigma being the variance) with a 5% error. Simulation of atmospherically aberrated images shows that although the functional form of the irradiance distribution changes considerably, the measurement errors decrease due to the increase in the effective sampling rate, which is given by the ratio between the spot size and the sampling interval.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
