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Title: Strain-free polished channel-cut crystal monochromators: a new approach and results

Abstract

The use of channel-cut crystal monochromators has been traditionally limited to applications that can tolerate the rough surface quality from wet etching without polishing. We have previously presented and discussed the motivation for producing channel cut crystals with strain-free polished surfaces [1]. Afterwards, we have undertaken an effort to design and implement an automated machine for polishing channel-cut crystals. The initial effort led to inefficient results. Since then, we conceptualized, designed, and implemented a new version of the channel-cut polishing machine, now called C-CHiRP (Channel-Cut High Resolution Polisher), also known as CCPM V2.0. The new machine design no longer utilizes Figure-8 motion that mimics manual polishing. Instead, the polishing is achieved by a combination of rotary and linear functions of two coordinated motion systems. Here we present the new design of C-CHiRP, its capabilities and features. Multiple channel-cut crystals polished using the C-CHiRP have been deployed into several beamlines at the Advanced Photon Source (APS). We present the measurements of surface finish, flatness, as well as topography results obtained at 1-BM of APS, as compared with results typically achieved when polishing flat-surface monochromator crystals using conventional polishing processes. Limitations of the current machine design, capabilities and considerations for strain-free polishingmore » of highly complex crystals are also discussed, together with an outlook for future developments and improvements.« less

Authors:
; ; ;
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
Argonne National Laboratory - Advanced Photon Source
OSTI Identifier:
1402059
DOE Contract Number:
AC02-06CH11357
Resource Type:
Conference
Resource Relation:
Conference: 2017 SPIE Optics + Photonics Conference, 08/06/17 - 08/10/17, San Diego, CA, US
Country of Publication:
United States
Language:
English

Citation Formats

Kasman, Elina, Montgomery, Jonathan, Huang, XianRong, and Assoufid, Lahsen. Strain-free polished channel-cut crystal monochromators: a new approach and results. United States: N. p., 2017. Web. doi:10.1117/12.2277605.
Kasman, Elina, Montgomery, Jonathan, Huang, XianRong, & Assoufid, Lahsen. Strain-free polished channel-cut crystal monochromators: a new approach and results. United States. doi:10.1117/12.2277605.
Kasman, Elina, Montgomery, Jonathan, Huang, XianRong, and Assoufid, Lahsen. 2017. "Strain-free polished channel-cut crystal monochromators: a new approach and results". United States. doi:10.1117/12.2277605.
@article{osti_1402059,
title = {Strain-free polished channel-cut crystal monochromators: a new approach and results},
author = {Kasman, Elina and Montgomery, Jonathan and Huang, XianRong and Assoufid, Lahsen},
abstractNote = {The use of channel-cut crystal monochromators has been traditionally limited to applications that can tolerate the rough surface quality from wet etching without polishing. We have previously presented and discussed the motivation for producing channel cut crystals with strain-free polished surfaces [1]. Afterwards, we have undertaken an effort to design and implement an automated machine for polishing channel-cut crystals. The initial effort led to inefficient results. Since then, we conceptualized, designed, and implemented a new version of the channel-cut polishing machine, now called C-CHiRP (Channel-Cut High Resolution Polisher), also known as CCPM V2.0. The new machine design no longer utilizes Figure-8 motion that mimics manual polishing. Instead, the polishing is achieved by a combination of rotary and linear functions of two coordinated motion systems. Here we present the new design of C-CHiRP, its capabilities and features. Multiple channel-cut crystals polished using the C-CHiRP have been deployed into several beamlines at the Advanced Photon Source (APS). We present the measurements of surface finish, flatness, as well as topography results obtained at 1-BM of APS, as compared with results typically achieved when polishing flat-surface monochromator crystals using conventional polishing processes. Limitations of the current machine design, capabilities and considerations for strain-free polishing of highly complex crystals are also discussed, together with an outlook for future developments and improvements.},
doi = {10.1117/12.2277605},
journal = {},
number = ,
volume = ,
place = {United States},
year = 2017,
month = 8
}

Conference:
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