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Application of silicon display for photo printer /Cheung, Yuk Lung. January 2004 (has links)
Thesis (M. Phil.)--Hong Kong University of Science and Technology, 2004. / Includes bibliographical references (leaves 80-82). Also available in electronic version. Access restricted to campus users.
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Single cell gap transflective liquid crystal displays and the use of photoalignment technology /Du, Tao. January 2009 (has links)
Includes bibliographical references.
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Mueller matrix imaging for skin cancer detectionBaldwin, Angela Michelle 30 September 2004 (has links)
Over one million Americans are afflicted with skin cancer each year. Even though skin cancer has a 95% cure rate, approximately 10,000 people die in the United States each year of this disease. The current ABCDE(F) detection method is not sensitive enough to detect skin cancer in its early stages and requires a biopsy for any suspicious lesions. A lot of unnecessary biopsies, which are painful and costly to the patient, are taken. Therefore, a noninvasive technique is needed that can accurately detect the presence of skin cancer. In this thesis, an optical approach will be presented that has potential to be a noninvasive skin cancer detection technique. Several morphological and biochemical changes occur as tissue becomes cancerous, and therefore the optical properties of the tissue can be used to detect skin cancer. A Mueller matrix imaging system has been developed by our group that measures the 16 or 36-element Mueller matrix, which completely describes the optical properties of the tissue sample. The system is automated and can collect the Mueller matrix in less than one minute. This system will be used to
image Sinclair swine, and data analysis techniques will be employed to determine if the system can distinguish between cancerous and noncancerous tissue. System software improvements will also be made, and a new calibration technique will be presented.
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Synthesis and characterization of C₂ symmetric liquid crystalline materialsHope-Ross, Kyle Andrew 11 1900 (has links)
A number of compounds were synthesized with the ultimate goal being the synthesis of
C₂ symmetric molecules which displayed thermotropic liquid crystalline behaviour. The
compounds prepared were 4-alkoxy benzophenones, 3,4-bis-alkoxy benzophenones, 4-
alkoxy dibenzylidene acetones, 3,4-bis-alkoxy dibenzylidene acetones and 4-alkoxy-
1, 9-diphenyl-nona-l,3,6,8-tetraen-5-ones. The length of the linear alkoxy side chain was
varied from C₆H₁₃ to C₁₂H₂₅.
All compounds were characterized by FTIR, ¹H, and ¹³C NMR spectroscopy. Mesophase
behaviour of the synthesized compounds was investigated using differential scanning
calorimetry and polarizing optical microscopy.
It was determined that both the alkoxy side chain length, as well as the number of alkoxy
side chains have an effect on the ability of this class of C₂ symmetric compounds to selfassemble
into liquid crystalline phases. In addition, the overall core size and extent of
conjugation also affected mesophase formation. The mono-alkoxy benzophenones and
dibenzylidene acetones were non-mesogenic, while all four of the mono-alkoxy 1,9-
diphenyl-nona-l,3,6,8-tetraen-5-ones (alkoxy side chain of lengths C₆H₁₃, C₈H₁₇, C₁₀H₂₁
and C₁₂H₂₅)self-assembled into nematic liquid crystalline phases. Increasing the number
of alkoxy side chains from one to two per aromatic moiety helped induce liquid
crystalline formation: the corresponding bis-C₆H₁₃ benzophenone and bis-C ₆H₁₃, bis
C₈H₁₇, and bis-C₁₀H₂₁ dibenzylidene acetones were mesogenic, displaying smectic A
(benzophenone) and nematic (dibenzylidene acetone) mesophases respectively.
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Synthesis and Characterization of Siloxane-terminated Liquid Crystals and Photochromic Fulgide Dopants for Liquid Crystal Photonics ApplicationsLi, LI 28 May 2009 (has links)
The goal of this thesis is to design both liquid crystal hosts and photochromic dopants terminated with short siloxane oligomers in order to produce homogeneous liquid crystal mixtures containing a photochromic component for liquid crystal photoswitches. Some of the liquid crystals terminated with short siloxane oligomers were also found to form 'de Vries'-type SmA phases, which minimize the formation of chevrons and zigzag defects that severely degrade the quality of electro-optic devices.
In the first part of the thesis, siloxane-terminated phenylpyrimidine liquid crystals were synthesized and characterized. They form SmC phases and, in some cases, SmA phases. Addition of a terminal halogen substituent on the alkoxy side-chain broadens the SmA temperature range. It was shown that combining a structural element that promotes the formation of a SmC phase with one that promotes the formation of a SmA phase in a mesogen with a 2-phenylpyrimidine core results in a maximum layer contraction of 1.6% for 2-(4-(11-(1,1,1,3,3,5,5-heptamethyltrisiloxanyl)undecyloxy)phenyl)-5-(1-chlorooctyloxy)pyrimidine (33a), which may be considered a ‘de Vries’ material.
As an extension of the result obtained in the first project, siloxane-terminated biphenyl benzoate and phenyl benzoate liquid crystals were synthesized and their phase behavior studied. They form SmC phases and, in some cases, SmA and SmI phases. Addition of a terminal chloro substituent on alkoxy side-chain results in a broader SmA temperature range and, in some cases, also affects the nature of the mesophase formed. The compound 4-[6-(1,1,1,3,3,5,5-heptamethyltrisiloxanyl)hexanoyloxy]phenyl 4-(8-chlorooctyloxy)benzoate (40b) is characterized by a maximum layer shrinkage of only 1.7%, which may be considered to possess some ‘de Vries’ character.
Finally, siloxane-terminated fulgide derivatives were designed as photochromic dopants for liquid crystal photoswitches. Compound 41 was designed and synthesized and proved to be an oil at room temperature. Solid fulgide precusors 42, 43a and 44b were then assessed as photochromic dopants in terms of fast switching and high quantum yield requirements of a photoswitch, and their photophysical properties were studied in solution. The isomer composition at the photostationary state suggests that the competition from E-Z isomerization is likely too high for compounds 42, 43a and 44b to be suitable as photochromic dopants for photoswitches. / Thesis (Ph.D, Chemistry) -- Queen's University, 2009-05-28 12:46:13.992
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Liquid crystal modulation of retroreflection : a low-power communication/location technologyHiggenbottom, Morris Scott 05 1900 (has links)
No description available.
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Brillouin scattering from organic layersGleed, D. G. January 1988 (has links)
No description available.
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Investigation of the mechanical and structural properties of cellulose tricarbanilate/polymethylacrylate blendsCameron, Juliet Dallas January 2000 (has links)
No description available.
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Design and development of liquid crystal lensesAshraf, Mujahid Al Islam. January 2006 (has links)
Thesis (MEng) - Swinburne University of Technology, Faculty of Engineering and Industrial Sciences, Centre for Micro-Photonics, 2006. / A thesis submitted for the degree of Master of Engineering, Centre for Micro-Photonics, Faculty of Engineering and Industrial Sciences, Swinburne University of Technology, 2006. Typescript. Includes bibliographical references (p. 74-77).
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Multiple-LED color-sequential liquid crystal on silicon projector /Li, Shuo. January 2008 (has links)
Thesis (M.Phil.)--Hong Kong University of Science and Technology, 2008. / Includes bibliographical references (leaves 105-108). Also available in electronic version.
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