NSN 5210-00-685-5545
Part Details | OPTICAL FLAT
5210-00-685-5545 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.
Alternate Parts: MIL026901CLASS1SIZE11, 5210-00-685-5545, 00-685-5545, 5210006855545, 006855545
Supply Group (FSG) | NSN Assigned | NIIN | Item Name Code (INC) |
---|---|---|---|
52 | JAN 01, 1963 | 00-685-5545 | 18274 ( OPTICAL FLAT ) |
REFERENCE DRAWINGS & PICTURES
Cross Reference | NSN 5210-00-685-5545
Part Number | Cage Code | Manufacturer |
---|---|---|
MIL026901CLASS1SIZE11 | 81349 | MILITARY SPECIFICATIONSPROMULGATED BY MILITARY |
Technical Data | NSN 5210-00-685-5545
Characteristic | Specifications |
---|---|
DESIGN TYPE | MASTER DOUBLE |
WORKING SURFACE FLATNESS ACCURACY | 0.00000200 INCHES NOMINAL |
DIAMETER | 4.000 INCHES NOMINAL |
THICKNESS | 0.750 INCHES NOMINAL |
CASE | PROVIDED |
NONDEFINITIVE SPEC/STD DATA | 1 CLASS AND 11 SIZE |