Polarization imaging apparatus with auto-calibration
Abstract
A polarization imaging apparatus measures the Stokes image of a sample. The apparatus consists of an optical lens set, a first variable phase retarder (VPR) with its optical axis aligned 22.5.degree., a second variable phase retarder with its optical axis aligned 45.degree., a linear polarizer, a imaging sensor for sensing the intensity images of the sample, a controller and a computer. Two variable phase retarders were controlled independently by a computer through a controller unit which generates a sequential of voltages to control the phase retardations of the first and second variable phase retarders. A auto-calibration procedure was incorporated into the polarization imaging apparatus to correct the misalignment of first and second VPRs, as well as the half-wave voltage of the VPRs. A set of four intensity images, I.sub.0, I.sub.1, I.sub.2 and I.sub.3 of the sample were captured by imaging sensor when the phase retardations of VPRs were set at (0,0), (.pi.,0), (.pi.,.pi.) and (.pi./2,.pi.), respectively. Then four Stokes components of a Stokes image, S.sub.0, S.sub.1, S.sub.2 and S.sub.3 were calculated using the four intensity images.
- Inventors:
- Issue Date:
- Research Org.:
- Boston Applied Technologies, Inc. (Woburn, MA)
- Sponsoring Org.:
- USDOE
- OSTI Identifier:
- 1093262
- Patent Number(s):
- 8514380
- Application Number:
- 12/763,173
- Assignee:
- Boston Applied Technologies, Inc. (Woburn, MA)
- Patent Classifications (CPCs):
-
G - PHYSICS G01 - MEASURING G01N - INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- DOE Contract Number:
- FG02-08ER85109
- Resource Type:
- Patent
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 47 OTHER INSTRUMENTATION
Citation Formats
Zou, Yingyin Kevin, Zhao, Hongzhi, and Chen, Qiushui. Polarization imaging apparatus with auto-calibration. United States: N. p., 2013.
Web.
Zou, Yingyin Kevin, Zhao, Hongzhi, & Chen, Qiushui. Polarization imaging apparatus with auto-calibration. United States.
Zou, Yingyin Kevin, Zhao, Hongzhi, and Chen, Qiushui. Tue .
"Polarization imaging apparatus with auto-calibration". United States. https://www.osti.gov/servlets/purl/1093262.
@article{osti_1093262,
title = {Polarization imaging apparatus with auto-calibration},
author = {Zou, Yingyin Kevin and Zhao, Hongzhi and Chen, Qiushui},
abstractNote = {A polarization imaging apparatus measures the Stokes image of a sample. The apparatus consists of an optical lens set, a first variable phase retarder (VPR) with its optical axis aligned 22.5.degree., a second variable phase retarder with its optical axis aligned 45.degree., a linear polarizer, a imaging sensor for sensing the intensity images of the sample, a controller and a computer. Two variable phase retarders were controlled independently by a computer through a controller unit which generates a sequential of voltages to control the phase retardations of the first and second variable phase retarders. A auto-calibration procedure was incorporated into the polarization imaging apparatus to correct the misalignment of first and second VPRs, as well as the half-wave voltage of the VPRs. A set of four intensity images, I.sub.0, I.sub.1, I.sub.2 and I.sub.3 of the sample were captured by imaging sensor when the phase retardations of VPRs were set at (0,0), (.pi.,0), (.pi.,.pi.) and (.pi./2,.pi.), respectively. Then four Stokes components of a Stokes image, S.sub.0, S.sub.1, S.sub.2 and S.sub.3 were calculated using the four intensity images.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {2013},
month = {8}
}