Surface topography measurement of plasma-facing materials by dual-wavelength phase-shifting speckle interferometry technique

Xiaoqian Cui; Hongbei Wang; Mengge Zhao; Yuanbo Li; Hongbin Ding

doi:10.1117/1.OE.57.1.014109

27 January 2018 Surface topography measurement of plasma-facing materials by dual-wavelength phase-shifting speckle interferometry technique

Xiaoqian Cui, Hongbei Wang, Mengge Zhao, Yuanbo Li, Hongbin Ding

Author Affiliations +

Optical Engineering, Vol. 57, Issue 1, 014109 (January 2018). https://doi.org/10.1117/1.OE.57.1.014109

Abstract

A dual-wavelength phase-shifting speckle interferometry approach has been proposed to diagnose the topography of plasma-facing materials (PFMs) in tokamak. The conventional speckle interferometric surface measurement, which uses single-wavelength, can offer excellent vertical resolution, but limitation in measuring large height step and phase ambiguity would occur during their application. To solve the problem, a dual-wavelength method was developed. Experiments were conducted on molybdenum (Mo) sample, which is related to PFMs of experimental advanced superconducting tokamak (EAST), and a laser ablation method was adopted to simulate the erosion happed on PFMs. The laser ablation craters were measured by both single-wavelength and dual-wavelength phase-shifting speckle interferometry, and a multistep phase-shifting method has been investigated for their effectiveness on reducing noise in calculating the phase map. This work demonstrates the superiority of the dual-wavelength speckle interferometry and the feasibility of applying the measurement system in topographic measurement of PFMs in EAST.

Citation Download Citation

Xiaoqian Cui, Hongbei Wang, Mengge Zhao, Yuanbo Li, and Hongbin Ding "Surface topography measurement of plasma-facing materials by dual-wavelength phase-shifting speckle interferometry technique," Optical Engineering 57(1), 014109 (27 January 2018). https://doi.org/10.1117/1.OE.57.1.014109

Received: 5 September 2017; Accepted: 27 December 2017; Published: 27 January 2018

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