• 한국정보디스플레이학회:학술대회논문집
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• 2000.01a
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• pp.41-42
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• 2000

Photosensitive polyimides containing cinnamoyl and coumarin side groups were synthesized in a high molecular weight, giving a good quality of films. Nematic liquid-crystal (LC) molecules on the film were aligned along the direction with an angle of $97-99^{\circ}$ respect to the polarization of ultraviolet (UV) light. The LC alignment was induced mainly by the photoaligned polymer chains made by the first UV-exposure even though the film was treated by multiple exposures with changing the polarization of UV light. From these results, it is concluded that the LC alignment on the film is induced by the photodimerization rather than the trans-cis photoisomerization.

• 한국정보디스플레이학회:학술대회논문집
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• 2000.01a
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• pp.107-108
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• 2000

We propose the method which is possible to fabricate the electrodes with the fine pattern and low resistance by photolithography and electroplating. The widths of pattern fabricated were 30, 50, 70 and 100um and the thickness could be up to $10{\mu}m$. The resistivity of the copper electrode electroplated was below $2.0{\mu}{\Omega}$ cm which is about half of photosensitive silver electrode. Dielectric layer was coated on the electrodes by screen printing and the pores harmful to the discharge were not formed after heat treatment. In the viewpoint of resistance and patterning, this method has much higher potential for large area display than other methods like screen printing, photosensitive conductive paste method and sputtering.

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07a
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• pp.480-483
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• 2005

We report on studies of photoalignment of cholesteric liquid crystals on photosensitive phenylon-based polymer. We found that reflective and electro-optical characteristics of cholesteric cells strongly depend on UV exposure doze. The optimized UV treatment of the polymer allowed us to obtain the same quality of alignment on standard rubbed polyimide orientants. At the same time, the photosensitive orientant possesses evident advantage of the effective control of cholesteric textures

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08a
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• pp.786-789
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• 2007

Fabrication of dot-patterned carbon nanotube (CNT) emitters with excellent field emission properties using photo-sensitive CNT paste is described. The photosensitive CNT paste showed good photopatternability, which led us to easily form $10-{\mu}m-diameter$ dot arrays. We presented a parametric study on formulating the photo-sensitive paste and their resultant field emission characteristics.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08a
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• pp.893-896
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• 2007

A series of new photosensitive polyimides having long alkoxy cinnamate chains were synthesized for liquid crystal (LC) photoalignment material. The polymer after irradiating linearly polarized UV light induced homogeneous and stable LC alignment. The chemical structure of the polymeric material was characterized and their photochemical LC alignment behavior was evaluated.

• Macromolecular Research
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• v.8 no.4
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• pp.172-178
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• 2000

We synthesized polymethacrylate and polyurethane bearing a photosensitive azobenzene chromophore. Photo-induced birefringence of the thin film was observed under a linearly polarized light(λ = 532 nm). Dynamic behaviors of birefringence in two polymers were investigated in terms of the rate constants of growth and decay. An induced dichroism was observed from polarized UV-VIS absorption spectroscopy. Layers of two photosensitive polymers were used for aligning liquid crystal (LC) molecules instead of one of the rubbed polyimide layers in the conventional twisted nematic cell. For producing homogeneous alignment of a nematic LC molecule, a linearly polarized light was exposed to the films of two polymers. The stability of the LC alignment upon the linearly polarized light exposure was also studied.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.21 no.5
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• pp.474-480
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• 2008

In order to make full color cholesteric displays, color filter-less R, G, B sub-pixel structured cholesteric LC cells have been studied. To make R, G, B colors, UV induced pitch variant chiral dopant was added to cholesteric LC mixtures. The concentration of the photo-sensitive chiral dopant was adjusted so that the initial state showed blue color and the color was changed from blue to green and red with increase of UV irradiation to the cholesteric cells. To prevent the mixing of R, G, B reflective sub-pixel liquid crystals, separation walls were formed using negative photo resister in boundary area between sub-pixels, Through the optimization of the material concentrations and UV irradiation condition, vivid R, G, B colors were achieved.

• Proceedings of the Korean Ceranic Society Conference
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• 2004.04b
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• pp.34.1-34.1
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• 2004

• Proceedings of the Korean Ceranic Society Conference
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• 2003.04a
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• pp.144.1-144
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• 2003

• Proceedings of the Korean Ceranic Society Conference
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• 2000.10a
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• pp.124.2-124
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• 2000