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Title: Quantum efficiency characterization of back-illuminated CCDs Part2: reflectivity measurements

Abstract

The usual quantum efficiency (QE) measurement heavily relies on a calibrated photodiode (PD) and the knowledge of the CCDs gain. Either can introduce significant systematic errors. But reflectivity can also be used to verify QE measurements. 1 - R > QE, where R is the reflectivity, and over a significant wavelength range, 1 - R = QE. An unconventional reflectometer has been developed to make this measurement. R is measured in two steps, using light from the lateral monochromator port via an optical fiber. The beam intensity is measured directly with aPD, then both the PD and CCD are moved so that the optical path length is unchanged and the light reflects once from the CCD; the PD current ratio gives R. Unlike traditional schemes this approach makes only one reflection from the CCD surface. Since the reflectivity of the LBNL CCDs might be as low as 2 percent this increases the signal to noise ratio dramatically. The goal is a 1 percent accuracy. We obtain good agreement between 1 - R and the direct QE results.

Authors:
; ; ; ;
Publication Date:
Research Org.:
Ernest Orlando Lawrence Berkeley NationalLaboratory, Berkeley, CA (US)
Sponsoring Org.:
USDOE Director. Office of Science. Office of AdvancedScientific Computing Research. Office of High Energy Physics
OSTI Identifier:
893744
Report Number(s):
LBNL-59378
R&D Project: PS1521; BnR: KA1503020; TRN: US200625%%495
DOE Contract Number:
DE-AC02-05CH11231
Resource Type:
Conference
Resource Relation:
Conference: Electronic Imaging 2006, San Jose, CA, 15 - 19January 2006
Country of Publication:
United States
Language:
English
Subject:
47 OTHER INSTRUMENTATION; ACCURACY; MONOCHROMATORS; OPTICAL FIBERS; PHOTODIODES; QUANTUM EFFICIENCY; REFLECTION; REFLECTIVITY; SIGNAL-TO-NOISE RATIO; WAVELENGTHS; CCD quantum efficiency reflectometer reflectivitycalibration

Citation Formats

Fabricius, Maximilian H., Bebek, Chris J., Groom, Donald E., Karcher, Armin, and Roe, Natalie A. Quantum efficiency characterization of back-illuminated CCDs Part2: reflectivity measurements. United States: N. p., 2006. Web.
Fabricius, Maximilian H., Bebek, Chris J., Groom, Donald E., Karcher, Armin, & Roe, Natalie A. Quantum efficiency characterization of back-illuminated CCDs Part2: reflectivity measurements. United States.
Fabricius, Maximilian H., Bebek, Chris J., Groom, Donald E., Karcher, Armin, and Roe, Natalie A. Thu . "Quantum efficiency characterization of back-illuminated CCDs Part2: reflectivity measurements". United States. doi:. https://www.osti.gov/servlets/purl/893744.
@article{osti_893744,
title = {Quantum efficiency characterization of back-illuminated CCDs Part2: reflectivity measurements},
author = {Fabricius, Maximilian H. and Bebek, Chris J. and Groom, Donald E. and Karcher, Armin and Roe, Natalie A.},
abstractNote = {The usual quantum efficiency (QE) measurement heavily relies on a calibrated photodiode (PD) and the knowledge of the CCDs gain. Either can introduce significant systematic errors. But reflectivity can also be used to verify QE measurements. 1 - R > QE, where R is the reflectivity, and over a significant wavelength range, 1 - R = QE. An unconventional reflectometer has been developed to make this measurement. R is measured in two steps, using light from the lateral monochromator port via an optical fiber. The beam intensity is measured directly with aPD, then both the PD and CCD are moved so that the optical path length is unchanged and the light reflects once from the CCD; the PD current ratio gives R. Unlike traditional schemes this approach makes only one reflection from the CCD surface. Since the reflectivity of the LBNL CCDs might be as low as 2 percent this increases the signal to noise ratio dramatically. The goal is a 1 percent accuracy. We obtain good agreement between 1 - R and the direct QE results.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Thu Jan 19 00:00:00 EST 2006},
month = {Thu Jan 19 00:00:00 EST 2006}
}

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