No other part numbers with same form, fit, and function found.
A flat, transparent piece of glass, generally of fused quartz, with one or both principal surfaces polished to within a few millionths of an inch of a true plane. It is used in conjunction with a monochromatic light source to measure the flatness of precision finished surfaces, and to determine the distance and parallelism between precision finished surfaces by comparison with known standards. In operation the flat is superimposed, reference surface downward, on the parts under test and when illuminated by monochromatic light the rays reflected from the reference surface are either reinforced or neutralized by the rays reflected from the surface under test producing interference bands which reveal any variations in the thickness of the film of air between surface under test and the flat. Excludes optical parallels.
NSN 6620-01-039-5468
NSN 5855-01-350-2454
NSN 5975-00-552-1764
NSN 2925-01-146-0278
NSN 5998-01-256-2533
NSN 5910-00-715-2338
NSN 6650-01-455-7562
NSN 6130-01-359-4228
NSN 5925-01-415-6551
NSN 6105-01-027-4792
NSN 5905-00-969-0738
NSN 6685-00-287-7564