[ATM] Optical flat part II

[Francis J. O'Reilly]

I spent another pleasant if not tedious two hours grinding the second surface of my blanks to be optical flats through the 320 SiO phase. I'm now ready to proceed with 500 SiO, then 22.5 micron AlO, 15, 9, 5 and finally 3. At four hours per grade, I'm looking at 24 hours of grinding before I'm ready to proceed to polishing. Then there will be the figuring.

This should keep me off the streets at night for a while.

Hopefully when I'm done, I'll have the experience needed to move onto my real project, a much larger flat to be used in an autocollimator.

Dick Parker has one of these devices, which he built. The ease of use based upon the intuitive nature of the images produced is astounding. While even Malacara does not go into great depth about the autocollimator and it is largely ignoerd in most circles, this is a far easier more accurate and reliable test to perform than the foucault test. I strongly recommend that anyone who is not familiar with the test to look into it. You will be impressed.  

Francis J. O'Reilly