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 6320-01-476-7702
NSN 5905-01-563-6873
NSN 5945-01-484-9325
NSN 5935-00-465-8497
NSN 5960-01-614-8005
NSN 5998-01-111-5491
NSN 6150-01-400-2914
NSN 5990-01-516-9665
NSN 5930-01-263-3980
NSN 7035-01-381-6185
NSN 5915-00-005-4114
NSN 6135-01-009-9135