Question

Working surfaces of Type-B optical flats are inclined to each other at which angle?

(a) 5 minute

(b) 10 minute

(c) 15 minute

(d) 20 minute

I have been asked this question in a job interview.

My doubt stems from Optical Flats in division Measurement by Light-Wave Interference of Engineering Metrology

Answer 1

Correct option is (a) 5 minute

To explain: The inclination for measuring surfaces of each type of Type-B optical flat is 5 minutes. Optical flats are usually stored in the wooden box to avoid shocks, dust and moisture during storage and transportation.