• Transactions on Electrical and Electronic Materials
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• 제16권3호
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• pp.117-123
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• 2015

Cholesteric liquid crystals are one dimensional photonic band-gap materials due to their birefringence and periodic structure. Dye doped cholesteric liquid crystals are self-assembling, mirror-less, low threshold laser structures that exhibit distributed feedback. In this review paper, we have presented the development in the field of lasing characteristics of dye doped cholesteric liquid crystals.

• Journal of Information Display
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• 제12권1호
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• pp.17-21
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• 2011

Aliquid crystal (LC) device switchable between the reflective and transmissive modes without sub-pixel division is proposed. By using dye-doped nematic LCs for the top LC layer, transflective displays with high reflectance were realized. It is expected that the proposed device can be applied to high-reflectance transflective devices for outdoor applications.

• Transactions on Electrical and Electronic Materials
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• 제13권5호
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• pp.221-224
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• 2012

The present paper reports the comparative optical behavior of a pure nematic mixture E-24 and its anthraquinone dye doped sample. The variation in the ordinary and extraordinary refractive index ($n_o$, $n_e$) of the pure and dye doped samples with temperature has been discussed and it has been found that doped sample have a less refractive index compared to the pure sample. The variation in the order parameter for pure and doped samples with temperature has been discussed and it has been seen that the doped sample has a higher order parameter; the possible reasons have been discussed. The variations in birefringence and optical transmittance have also been presented here.

• 한국광학회지
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• 제26권2호
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• pp.110-114
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• 2015

본 논문에서는 스위칭 가능한 브래그 반사판의 한 종류인 콜레스테릭 액정 셀에 염료를 주입함으로써 입사각에 따라 단파장대로 이동된 반사광을 제거하는 셀을 구현하였다. 액정과 카이랄 도펀트를 일정 비율로 혼합하여 원하는 파장대역을 반사하는 콜레스테릭 액정 셀을 제작하였고, 이에 특정한 파장대역을 흡수하는 성질을 가지는 이색성 염료를 혼합함으로써, 빛의 입사각이 증가할 때 단파장으로 이동된 빛을 흡수하여 초기에 설계된 색을 유지할 수 있다. 염료를 혼합하지 않은 콜레스테릭 액정 셀에서는 입사각에 따라서 반사 된 빛이 눈에 띄게 단파장대로 이동되는데 반해, 제안된 방법에서는 염료의 혼합 비율이 1, 2 wt%로 증가할수록 단파장대로 이동된 빛을 더 잘 흡수하는 것을 확인하였다.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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• pp.838-841
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• 2006

Orientational alignment patterns proved that they are very useful for realizing diverse properties of liquid crystals. Here we tried to produce the patterns combining interfered laser light and double irradiations. A photo-isomerizable polymer doped with azo dye, which induce uniform liquid crystal alignment to the uniform laser irradiation, was used as the alignment layer. Double irradiations into two orthogonal directions brought the orientation patterns similar to the checkerboard. It indicates the possibility of bistability on those patterns.

• 한국광학회:학술대회논문집
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• 한국광학회 2005년도 제16회 정기총회 및 동계학술발표회
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• pp.322-323
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• 2005

• 한국광학회:학술대회논문집
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• 한국광학회 2008년도 하계학술발표회 논문집
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• pp.191-192
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• 2008

• 한국광학회:학술대회논문집
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• 한국광학회 2006년도 하계학술발표회 논문집
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• pp.433-434
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• 2006

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2002년도 International Meeting on Information Display
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• pp.494-497
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• 2002

The influence of isomeric state of doped azo dye on the $B_7$ phase of bent-shaped liquid crystal (LC) is studied. It was found that modulating the isomeric trans-cis state of azo dye can change the molecular arrangement of the bent-shaped LCs. To identify these phenomena the observations of microscopic texture, electro-optic response, second harmonic wave generation (SHG) and switching current were carried out..

• Journal of Information Display
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• 제9권4호
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• pp.11-14
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• 2008

A highly efficient organic light-emitting diode (OLED) with an in-cell polarizer made of an imprinted liquid crystalline polymer (LCP) layer doped with dichroic dye molecules is presented. The in-cell polarizer was found to be capable of effectively polarizing the emission light of the OLED and of significantly improving the luminance through the periodic microstructures fabricated using an imprinting method. This type of OLED with an imprinted in-cell polarizer is useful for efficient light source applications in liquid crystal displays (LCDs).