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 6105-01-212-3857
NSN 7035-01-500-5998
NSN 6610-01-587-1803
NSN 4140-01-526-4090
NSN 5855-00-869-3635
NSN 6135-00-726-4142
NSN 5985-01-037-1736
NSN 7035-01-422-4642
NSN 5905-01-394-3728
NSN 5920-01-347-5852
NSN 5960-00-275-7497
NSN 5996-01-054-3226