Numerical - Number of fringes - Metrology & Quality Control

Q.  An interferometer is used to measure a surface of 1.85 mm. Calculate number of fringes, when λ = 0.659 μm.
- Published on 07 Aug 15

a. 5614.567
b. 5000.236
c. 2807.283
d. None of the above

ANSWER: 5614.567
 

    Discussion

  • Sravanthi   -Posted on 26 Oct 15
    - The measurements made by an interferometer are based on light wave interference phenomenon.

    Given: λ = 0.659 μm

    Solution:

    The length of a surface is divided by half wavelength of light to find nominal fraction.

    λ / 2 = 0.659 / 2 = 0.3295 x 10-3 mm

    Number of fringes = 1.85 / 0.3295 x 10-3 = 5614.567

    Therefore, 5614.567 are the number of fringes obtained when λ = 0.659 μm on a surface of 1.85 mm

Post your comment / Share knowledge


Enter the code shown above:
 
(Note: If you cannot read the numbers in the above image, reload the page to generate a new one.)