National Item Identification Number
01-189-1619
011891619
5210-01-189-1619
5210011891619
National Stock Number
Item Name
OPTICAL FLAT
Federal Supply Class
5210
Description
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.
Commercial and Government Entity Code (Supplier Data)
62679
VAN KEUREN
41 LORING DRIVE
FRAMINGHAM
MA
01702
800-825-4272
Reference Numbers (Part Numbers)
GG-O-635
24-10-10SMM
Required Categories
DESIGN TYPE
MATERIAL
WORKING SURFACE FLATNESS ACCURACY
CASE
SPEC/STD CONTROL
Required Description
MASTER SINGLE
QUARTZ, FUSED
0.00000200 INCHES NOMINAL
NOT PROVIDED
81348
GG