Patterned Liquid Crystal Polymer Retarders, Polarizers, and Sources

Persistent Link:
http://hdl.handle.net/10150/228152
Title:
Patterned Liquid Crystal Polymer Retarders, Polarizers, and Sources
Author:
Myhre, Graham
Issue Date:
2012
Publisher:
The University of Arizona.
Rights:
Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.
Abstract:
Liquid crystals are traditionally aligned via a rubbed substrate. The rubbing creates anisotropic defects and strain in the material which provide an energetically favorable orientation for the liquid crystal (LC). This is a well-developed technology that is used in virtually all liquid crystal displays (LCDs). However, it is only capable of uniform alignment on a large planar substrate. This work utilizes a new class of photoalignment materials (PM) that replace the traditional buffing technique. PMs allow for patterned LC alignment using polarized photo-lithography. Further, instead of using a nematic liquid crystal, a UV curable liquid crystal polymer (LCP) is coated on this patterned alignment material. This generates a cured, aligned, and patterned thin film that has retardance and diattenuation if a dichroic dye is incorporated in the LCP. Using these materials and methods, retarders, polarizers, and polarized fluorescent sources are fabricated with dimensions as small as a few microns. In addition to exploring the material and processing properties of the PM and LCP system, arrays of micropolarizer are fabricated for the construction of a prototype polarization camera, termed an imaging polarimeter. An imaging polarimeter is a device that measures not only the intensity but also the polarization state of a light field. My imaging polarimeter design incorporates a patterned LCP polarizer focal plane array (FPA) that is aligned and mounted to a charge-couple-device (CCD) image sensor. A polarizer FPA allows an individual pixel on a CCD sensor to detect a unique polarization state, such as a specific linear polarization orientation or right or left handed circular polarization. Neighboring pixels are designed to detect different states and each cluster can then estimate the incident polarization state. Results of a linear LCP polarimeter operating in the visible spectrum are presented.
Type:
text; Electronic Dissertation
Keywords:
Liquid Crystal; Photo Alignment; Polarimeter; Polarized Fluorescence; Optical Sciences; Dichroic Dye; Focal Plane Array
Degree Name:
Ph.D.
Degree Level:
doctoral
Degree Program:
Graduate College; Optical Sciences
Degree Grantor:
University of Arizona
Advisor:
Pau, Stanley

Full metadata record

DC FieldValue Language
dc.language.isoenen_US
dc.titlePatterned Liquid Crystal Polymer Retarders, Polarizers, and Sourcesen_US
dc.creatorMyhre, Grahamen_US
dc.contributor.authorMyhre, Grahamen_US
dc.date.issued2012-
dc.publisherThe University of Arizona.en_US
dc.rightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.en_US
dc.description.abstractLiquid crystals are traditionally aligned via a rubbed substrate. The rubbing creates anisotropic defects and strain in the material which provide an energetically favorable orientation for the liquid crystal (LC). This is a well-developed technology that is used in virtually all liquid crystal displays (LCDs). However, it is only capable of uniform alignment on a large planar substrate. This work utilizes a new class of photoalignment materials (PM) that replace the traditional buffing technique. PMs allow for patterned LC alignment using polarized photo-lithography. Further, instead of using a nematic liquid crystal, a UV curable liquid crystal polymer (LCP) is coated on this patterned alignment material. This generates a cured, aligned, and patterned thin film that has retardance and diattenuation if a dichroic dye is incorporated in the LCP. Using these materials and methods, retarders, polarizers, and polarized fluorescent sources are fabricated with dimensions as small as a few microns. In addition to exploring the material and processing properties of the PM and LCP system, arrays of micropolarizer are fabricated for the construction of a prototype polarization camera, termed an imaging polarimeter. An imaging polarimeter is a device that measures not only the intensity but also the polarization state of a light field. My imaging polarimeter design incorporates a patterned LCP polarizer focal plane array (FPA) that is aligned and mounted to a charge-couple-device (CCD) image sensor. A polarizer FPA allows an individual pixel on a CCD sensor to detect a unique polarization state, such as a specific linear polarization orientation or right or left handed circular polarization. Neighboring pixels are designed to detect different states and each cluster can then estimate the incident polarization state. Results of a linear LCP polarimeter operating in the visible spectrum are presented.en_US
dc.typetexten_US
dc.typeElectronic Dissertationen_US
dc.subjectLiquid Crystalen_US
dc.subjectPhoto Alignmenten_US
dc.subjectPolarimeteren_US
dc.subjectPolarized Fluorescenceen_US
dc.subjectOptical Sciencesen_US
dc.subjectDichroic Dyeen_US
dc.subjectFocal Plane Arrayen_US
thesis.degree.namePh.D.en_US
thesis.degree.leveldoctoralen_US
thesis.degree.disciplineGraduate Collegeen_US
thesis.degree.disciplineOptical Sciencesen_US
thesis.degree.grantorUniversity of Arizonaen_US
dc.contributor.advisorPau, Stanleyen_US
dc.contributor.committeememberMilster, Thomas D.en_US
dc.contributor.committeememberChipman, Russell A.en_US
dc.contributor.committeememberPau, Stanleyen_US
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