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Title: Spatial resolution limits for synchrotron-based infrared spectromicroscopy

Abstract

Detailed spatial resolution tests were performed on beamline 1.4.4 at the Advanced Light Source synchrotron facility in Berkeley, CA. The high-brightness synchrotron source is coupled at this beamline to a Thermo-Electron Continumum XL infrared microscope. Two types of resolution tests in both the mid-IR (using a KBr beamsplitter and an MCT-A* detector) and in the near-IR (using a CaF2 beamsplitter and an InGaAS detector) were performed and compared to a simple diffraction-limited spot size model. At the shorter wavelengths in the near-IR the experimental results begin to deviate from only diffraction-limited. The entire data set is fit using a combined diffraction-limit and demagnified electron beam source size model. This description experimentally verifies how the physical electron beam size of the synchrotron source demagnified to the sample stage on the endstation begins to dominate the focussed spot size and therefore spatial resolution at higher energies. We discuss how different facilities, beamlines, and microscopes will affect the achievable spatial resolution.

Authors:
; ;
Publication Date:
Research Org.:
Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
Sponsoring Org.:
Advanced Light Source Division
OSTI Identifier:
937218
Report Number(s):
LBNL-834E
Journal ID: 1350-4495; TRN: US0805755
DOE Contract Number:
DE-AC02-05CH11231
Resource Type:
Journal Article
Resource Relation:
Journal Name: Infrared Physics&Technology; Journal Volume: 51; Journal Issue: 5; Related Information: Journal Publication Date: May 2008
Country of Publication:
United States
Language:
English
Subject:
47; 43; ADVANCED LIGHT SOURCE; ELECTRON BEAMS; MICROSCOPES; RESOLUTION; SPATIAL RESOLUTION; SYNCHROTRONS; WAVELENGTHS; Synchrotron; Spatial resolution; Microscopy; Spectromicroscopy; Imaging; Diffraction

Citation Formats

Levenson, Erika, Lerch, Philippe, and Martin, Michael C. Spatial resolution limits for synchrotron-based infrared spectromicroscopy. United States: N. p., 2007. Web.
Levenson, Erika, Lerch, Philippe, & Martin, Michael C. Spatial resolution limits for synchrotron-based infrared spectromicroscopy. United States.
Levenson, Erika, Lerch, Philippe, and Martin, Michael C. Mon . "Spatial resolution limits for synchrotron-based infrared spectromicroscopy". United States. doi:. https://www.osti.gov/servlets/purl/937218.
@article{osti_937218,
title = {Spatial resolution limits for synchrotron-based infrared spectromicroscopy},
author = {Levenson, Erika and Lerch, Philippe and Martin, Michael C.},
abstractNote = {Detailed spatial resolution tests were performed on beamline 1.4.4 at the Advanced Light Source synchrotron facility in Berkeley, CA. The high-brightness synchrotron source is coupled at this beamline to a Thermo-Electron Continumum XL infrared microscope. Two types of resolution tests in both the mid-IR (using a KBr beamsplitter and an MCT-A* detector) and in the near-IR (using a CaF2 beamsplitter and an InGaAS detector) were performed and compared to a simple diffraction-limited spot size model. At the shorter wavelengths in the near-IR the experimental results begin to deviate from only diffraction-limited. The entire data set is fit using a combined diffraction-limit and demagnified electron beam source size model. This description experimentally verifies how the physical electron beam size of the synchrotron source demagnified to the sample stage on the endstation begins to dominate the focussed spot size and therefore spatial resolution at higher energies. We discuss how different facilities, beamlines, and microscopes will affect the achievable spatial resolution.},
doi = {},
journal = {Infrared Physics&Technology},
number = 5,
volume = 51,
place = {United States},
year = {Mon Oct 15 00:00:00 EDT 2007},
month = {Mon Oct 15 00:00:00 EDT 2007}
}
  • Spatial resolution tests were performed on beamline 1.4.4 at the Advanced Light Source in Berkeley, CA, USA, a third-generation synchrotron light source. This beamline couples the high-brightness synchrotron source to a Thermo-Electron Continumum XL infrared microscope. Two types of resolution tests were performed in both the mid-IR and near-IR. The results are compared with a diffraction-limited spot size theory. At shorter near-IR wavelengths the experimental results begin to deviate from diffraction-limited so a combined diffraction-limit and electron-beam-source-size model is employed. This description shows how the physical electron beam size of the synchrotron source begins to dominate the focused spot sizemore » at higher energies. The transition from diffraction-limited to electron-beam-size-limited performance is a function of storage-ring parameters and the optical demagnification within the beamline and microscope optics. The discussion includes how different facilities, beamlines and microscopes will affect the achievable spatial resolution. As synchrotron light sources and other next-generation accelerators such as energy-recovery LINACs and free-electron lasers achieve smaller beam emittances, beta-functions and/or energy spreads, diffraction-limited performance can continue to higher-energy beams, perhaps ultimately into the extreme ultraviolet.« less
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  • Spectroscopy and spatially resolved chemical imaging of biological materials using an infrared microscope is greatly enhanced with confocal image plane masking to 5-6 {mu} with a third generation microspectrometer and illumination with a synchrotron radiation source compared to globar illuminated and array detection or singly masked system. Steps toward this instrumental achievement are illustrated with spectra and images of biological tissue sections, including single cells, brain, aorta, and grain specimens. A recent, customized synchrotron infrared microspectrometer installation enables focal plane array detection to achieve both rapid and high definition chemical imaging. Localization of the ester carbonyl population in single modifiedmore » starch granules was used to provide direct comparison of the two advanced imaging capabilities.« less