Enhanced phase-stepped interferometry via appropriate filtering

M. I. Younus; Mohammad S. Alam

doi:10.1117/1.602262

1 November 1999 Enhanced phase-stepped interferometry via appropriate filtering

M. I. Younus, Mohammad S. Alam

Optical Engineering, Vol. 38, Issue 11, (November 1999). https://doi.org/10.1117/1.602262

Phase-stepped interferometry is a well known technique for the measurement of surface deformation. Since in this technique phase characteristics of a linear system is computed using the arctangent function, in some points the raw phase data exceeds the value 2?. Moreover the surface roughness, phase unwrapping, and extra noise imposed from the environment makes the surface look like an original surface with huge impulsive noise and simply using PSI technique does not produce an accurately reconstructed surface. In this paper, a filtering technique is proposed that suppresses the noise and enhances the image quality. It is shown that the raw phase data prefiltered by a mean filter eliminates Gaussian noise. Then, after proper unwrapping treatment, the data should be filtered with a rank conditioned median (RCM) filter. The RCM filter is very effective at treating impulsive type noise while preserving step edges without blurring.

Citation Download Citation

M. I. Younus and Mohammad S. Alam "Enhanced phase-stepped interferometry via appropriate filtering," Optical Engineering 38(11), (1 November 1999). https://doi.org/10.1117/1.602262

Published: 1 November 1999

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available