Reading Optical Flats Part 2

Beyond some hit and miss experimenting, much of what I’ve learned about interpreting optical flat fringe patterns comes from a 1950s DoALL book titled: “The Science of Precision Measurement”. Illustrations from this book and other DoALL sources are included with the permission of DGI Supply, a DoALL Company: https://www.dgisupply.com/page/page.h...

Although universally known for their bandsaws, in the last half of the 20th century DoALL manufactured and distributed a wide variety of machining products and offered a full line of metrology equipment as well as extensive literature describing its use. This book is a product of that educational initiative and the best reference I’ve found for extracting detailed, quantitative surface contour information using optical flats. It is available for online reading at: https://babel.hathitrust.org/cgi/pt?i...

Another DoALL book, first published in 1964 and, again, out of print, titled “Fundamentals of Dimensional Metrology” by Ted Busch for the Wilkie Brothers Foundation builds upon the earlier book’s optical flat content and is available on the used book market. The Wilkie Brothers Foundation is an educational and development arm of DoALL, founded by Leighton Wilkie, the founder of DoALL, and his brothers.

There are many offerings discussing aspects of optical flats on the internet. Here are a few links to things that might be of interest:

https://en.wikipedia.org/wiki/Optical...

http://www.starrett-webber.com/Fringe...
https://www.kemet.co.uk/blog/lapping/...
https://www.kemet-international.com/u...
https://www.advancedoptics.com/optica...
https://www.gagesite.com/documents/Me...
https://www.lapmaster-wolters.com/opt...
http://www.surfacefinishes.com/produc...