To: atm{at}shore.net
From: mdholm{at}telerama.com
Reply-To: mdholm{at}telerama.com


Those of you ATM's who are good at physical optics and math please take a
look at this paper.  I have only given it a brief look so far, but it looks
like it might be interesting and possibly not too hard to implement. 
Advantages, if I read it correctly, would include improved contrast of the
Ronchi bands.

An improved Ronchi test with extended source Joseph Braat and Augustus J.E.M. Janssen

Abstract
A modified Ronchi test with an extended source is presented. By using a
matched pair of source grating and Ronchi grating, a pure shearogram
between two shifted wavefronts is obtained and the extra interference with
other disturbing grating orders is largely suppressed by using a specific
grating layout.

Here is the link:

http://www.optica.tn.tudelft.nl/Publications/braat55.pdf

Mark Holm
mdholm{at}telerama.com

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