IMAGE MAPPED SPECTROPOLARIMETRY

• US 20130321806A1
• Filed: 11/30/2011
• Published: 12/05/2013
• Est. Priority Date: 12/14/2010
• Status: Active Grant

• Current Assignee: Rice University
• Original Assignee: Rice University
• Inventors: Kester, Robert T., Tkaczyk, Tomasz S.
• Granted Patent: US 9,239,263 B2
• Time in Patent Office: Days
• US Class Current: 356/327
• CPC Class Codes: G01J 3/02 Details
• CPC Class Codes: G01J 3/0224 using polarising or depolarising elements
• CPC Class Codes: G01J 3/2823 Imaging spectrometer
• CPC Class Codes: G01J 3/447 Polarisation spectrometry
• CPC Class Codes: G01J 4/04 Polarimeters using electric detection means G01J4/02 takes precedence

Abstract

A method for imaging a sample, the method includes, during a single acquisition event, receiving a first polarization-encoded EM field for a first point and a second polarization-encoded EM field for a second point. The method further includes re-directing the first polarization-encoded EM field along a first pre-determined direction to a first location on a dispersing re-imager and the second polarization-encoded EM field along a second pre-determined direction to a second location on the dispersing re-imager. The method further includes spectrally dispersing the first polarization-encoded EM field to obtain a first spectrum, re-imaging the first spectrum onto a first location on a detector, spectrally dispersing the second polarization-encoded EM field to obtain a second spectrum, re-imaging the second spectrum onto a second location on the detector, and detecting the first re-imaged spectrum and the second re-imaged spectrum.

Claims

1. A method for imaging a sample, comprising:

during a single acquisition event;

receiving a plurality of polarization-encoded electromagnetic (EM) fields from a plurality of points on the sample comprising a first polarization-encoded EM field for a first point and a second polarization-encoded EM field for a second point;

redirecting the first polarization-encoded EM field along a first pre-determined direction to a first location on a dispersing re-imager and the second polarization-encoded EM field along a second pre-determined direction to a second location on the dispersing re-imager;

spectrally dispersing the first polarization-encoded EM field to obtain a first spectrum;

re-imaging the first spectrum onto a first location on a detector;

spectrally dispersing the second polarization-encoded EM field to obtain a second spectrum;

re-imaging the second spectrum onto a second location on the detector; and

detecting the first re-imaged spectrum and the second re-imaged spectrum.

2. The method of claim 1, wherein the first polarization-encoded EM field comprises a plurality of EM fields emanating along a z-direction in the sample for the first point.

3. A system, comprising:

an image mapper configured to, during a single acquisition event;

receive a plurality of polarization-encoded electromagnetic (EM) fields from a plurality of points on a sample comprising a first polarization-encoded EM field for a first point and a second polarization-encoded EM field for a second point;

redirect the first polarization-encoded EM field along a first pre-determined angle to a first location on a dispersing re-imager and the second polarization-encoded EM field along a second pre-determined angle to a second location on the dispersing re-imager;

the dispersing re-imager configured to;

spectrally disperse the first polarization-encoded EM field to obtain a first spectrum;

re-image the first spectrum on to a first location on a detector;

spectrally disperse the second polarization-encoded EM field to obtain a second spectrum;

re-image the second spectrum on to a second location on the detector;

the detector configured to;

detect the first re-imaged spectrum and the second re-imaged spectrum.

4. The system of claim 3, further comprising:

a spectropolarimeter configured to generate the plurality of polarization-encoded EM fields and provide the plurality of polarization-encoded EM fields to the image mapper.

5. The system of claim 4, wherein the spectropolarimeter comprises a first retarder and a second retarder, where a slow axis of the first retarder is oriented at a 45-degree angle relative to a slow axis of second retarder about an optical axis of the spectropolarimeter.

6. The system of claim 5, wherein the spectropolarimeter further comprises a polarizer, wherein a transmission axis of the polarizer is parallel to a fast axis of the first retarder.

7. The system of claim 3, wherein the image mapper is refractive.

8. The system of claim 7, wherein the dispersing re-imager comprises an array of field of view correctors configured to receive the plurality of polarization-encoded EM fields from the image remapper and to shift each of the plurality of polarization-encoded EM fields to obtained a plurality of shifted polarization-encoded EM fields.

9. The system of claim 8, wherein the dispersing re-imager further comprises an array of dispersive elements configured to receive the plurality of shifted polarization-encoded EM fields and to spectrally disperse each of the plurality of spectra comprising the first spectrum and the second spectrum.

10. The system of claim 9, wherein the dispersing re-imager further comprises an array of reimaging lenses configured to the plurality of spectra and to re-image the plurality of spectra on to the detector.

11. The system of claim 3, wherein the detector comprises a two-dimensional (2D) array of EM radiation detectors.

12. The system of claim 11, the detector is a charged-couple device.