• 한국정보디스플레이학회:학술대회논문집
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• 2005.07a
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• pp.199-202
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• 2005

We have studied the origin of coherent director rotation [CDR] as well as memory behavior in thiol-ene polymer stabilized ferroelectric liquid crystal [FLC]. The ene constituents are found to be always located at the inter-layer space and induce the coherent director rotation motion of liquid crystal molecule. On the other hand, the thiols are more intersticed between ferroelectric liquid crystal molecules at intra-layer as the thiol gets longer, and these intersticed thiols enhance the multistability and the resolution of memory state of FLCs.

• 한국정보디스플레이학회:학술대회논문집
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• 2004.08a
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• pp.287-288
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• 2004

We report on the development of ferronematic liquid crystals, new materials that consist of a dilute suspension of ferroelectric particles in a nematic liquid crystal host. The particles share their ferroelectric properties with the nematic liquid crystal and impose a spontaneous dielectric polarization of about 10 nC/$cm^2$ to the entire medium, typical for many ferroelectric liquid crystals. As expected, these new materials have enhanced dielectric anisotropy and are sensitive to the sign of an applied electric field. The potential of their use in a number of devices are discussed.

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.163-166
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• 2006

We found dramatic changes of the properties of LCs by dispersing ferroelectric nanoparticles. Specifically, ferroparticles greatly increase the nematic-isotropic transition temperature, birefringence and dielectric anisotropy of the LC. Ferroelectric nanoparticles/LCs colloids offer a simple and effective means to precisely control the physical properties of LC materials and optimize them for display applications.

• 한국정보디스플레이학회:학술대회논문집
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• 2004.08a
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• pp.1229-1232
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• 2004

The ratio of optimized concentration on optical characteristics for phase-separated composite organic films (PSCOF) liquid crystal display is 30% of pre-polymer (NOA65) and 70% of ferroelectric liquid crystal (Felix). The layer structure in ferroelectric liquid crystal cell made by 30% NOA65 and 70% Felix materials is tilt-bookshelf layer structure. The angle of tilt-bookshelf structure are 17$^{\circ}$, 12$^{\circ}$ which are almost same of tilt angle of ferroelectric liquid crystal in Sm $C^{\ast}$ phase. We know that this result is from compensating the layer buckling. In this paper, we will discuss the effect of layer structure in PSCOF cell on ratio of concentration between pre-polymer and liquid crystal by x-ray measurements. We believe that technology of PSCOF is a good solution to solve the problems of align-defect and mechanical shock for future TV application and plastic LCD.

• Journal of the Chungcheong Mathematical Society
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• v.23 no.3
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• pp.571-588
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• 2010

We introduce the Landau-de Gennes model in order to understand molecular structures in ferroelectric liquid crystals. We investigate equilibrium configurations of the governing energy functional by means of bifurcation analysis. In particular, we obtain periodic solutions of the functional, which is a signature of a rich variety of applications of ferroelectric materials.

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.344-347
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• 2008

We fabricated the outer type-dynamic microlens array using a surface-stabilized ferroelectric liquid crystal, UV curable polymer and the stacked liquid crystalline polymer. The outer type-microlens array has a lower driving voltage and fast switching property. It is applicable to a variety of optical systems.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08a
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• pp.109-112
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• 2007

A new concept of the microlens array is fabricated using a birefringent layer on the concave microlens array. The stacked layers of liquid crystalline polymer (LCP) and the UV epoxy focus an incident light due to the surface relief structure. The ferroelectric liquid crystal layer was added to control the focusing intensity with a fast switching time.

• Journal of Information Display
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• v.4 no.1
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• pp.1-8
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• 2003

Recent progress in both low pretilt and high pretilt defect free C1 surface stabilized ferroelectric liquid crystal (SSFLC) devices is reviewed. First, by numerical calculation to investigate the balance between surface azimuthal anchoring energy and bulk elastic energy within the confined chevron layer geometry of C1 and C2, it is possible to achieve a zigzag free C1 state by low azimuthal anchoring alignment with a low pretilt angle. The critical azimuthal anchoring coefficient for defect free C1 state is calculated. Its relationship with elastic constant, chevron angle as well as surface topography effect are also discussed. Second, using $5^{\circ}$ oblique SiO deposition alignment method a defect free, large memory angle, high contrast ratio and bistable C1 SSFLC display, which has potential for electronic paper applications has also been developed. The electrooptical properties and bistability of this device have been investigated. Various aspects of defect control are also discussed.

• Journal of Information Display
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• v.13 no.1
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• pp.31-36
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• 2012

Ferroelectric liquid crystal parameters, spontaneous polarization, and transition temperature were studied as a function of cell thickness. These parameters were found to increase with increasing cell thickness, but an exception was observed for the transition temperature in the case of a thin cell. A simple Landau model is presented to interpret the theoretical and experimental observations. The anomalous behavior is attributed to the electroclinic effect and is explained using the Landau model.

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07a
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• pp.338-341
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• 2005

We have examined the aspects of the orientational ordering deformation of ferroelectric liquid crystal during bending performance of plastic substrate by analyzing the polarizing optical microscope texture and the birefringence of the cell. Striped texture becomes more prominent as the radius of curvature of substrate gets smaller. The optic axis of the adjacent stripes domain was not same and the relative angle between them becomes larger as the radius of curvature gets smaller. Especially, the optic axis rotation angle of one domain was lager than the other and the liquid crystal molecules in each domain became more coherent. In addition, the birefringence data with obliquely incident light shows the polar direction shift of liquid crystal molecule by bending performance.