• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.11a
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• pp.388-389
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• 2007

A transflective liquid crystal displays driven by fringe field switching mode of new concept is being suggested. The FFS mode is known to have the different twist angle distribution at the position when an operating voltage is applied. We make the cell design by using the different twist angle which has some region decided on transmissive region and other region used to reflective region. By optimizing simulation condition in the concept, we proposed new tansflective LCDs using FFS mode with single gap and single gamma characteristics.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.18 no.8
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• pp.720-723
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• 2005

We studied the quantitativity of the image sticking which is occured by the resicual DC in the fringe-electric field switching (FFS) mode. Actually, in the FFS mode driven by the strong fringe electric field, the asymmetric residual DC was formed in the bottom substrate. It made the impurity ion stick to the alignment layer such as polyimde layer. Thus, the differnece of the luminance existes after the stress check pattern is applied to the panel so that we can see the image sticking. This image sticking decreases as the residual DC value between specific patterns decreases. Therefore, it is necessary to control the residual DC for the FFS mode with the high image quality. It is possible to eliminate the image stiking when the extra pixel voltage is applied through the circuit tunning for reducing the difference of residual DC accroding to the panel position.

• 한국정보디스플레이학회:학술대회논문집
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• 2000.01a
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• pp.5-6
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• 2000

Fringe-field switching (FFS) technology exhibiting a high image quality has been developed. In this paper, one pixel concept, manufacturing process, materials, and electro-optic characteristics of FFS mode comparing with conventional in-plane switching mode, and its possible application to reflective type will be discussed.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.07a
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• pp.518-519
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• 2005

We have studied the transmittance of fringe-filed switching(FFS) using a liquid crystal with positive dielectric anisotropy. Generally, FFS having positive dielectric anisotropy has less transmittance than FFS using negative dielectric anisotropy. FFS mode transmittance depends on horizontal director deformation, however fringe filed is composed of vertical and horizontal field. Vertical field in the middle of electrode suppresses the transmittance of FFS mode, especially when we use positive one. So, it is important to prevent the LC director from the effect of vertical field. We changed the splay elastic constant and checked the transmittance. The transmittance of FFS having positive dielectric anisotropy was improved. Less tilted LC directors improve the transmittance of FFS using positive dielectric anisotropy. We can improve the transmittance by using LC which have high splay elastic constant when another LC properties are equal.

• Korean Journal of Optics and Photonics
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• v.25 no.6
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• pp.301-310
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• 2014

Recently, the fringe-field switching (FFS) mode in liquid crystal displays has been used mainly for high image quality and high-resolution liquid crystal displays (LCDs). In this review paper, the fundamental switching principle of the FFS mode, with its excellence over other LC modes in electro-optic performance, will be described. In addition, the development history, present technical issues, and future of the FFS LCD will be discussed.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.16 no.3
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• pp.224-230
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• 2003

The voltage-dependent transmittance curve of a homogeneously aligned liquid crystal (LC) cell driven by fringe-electric field(named FFS mode) was studied, while changing dielectric anisotropy of a LC. The results show that for a LC with positive dielectric anisotropy while positioning at initial position. Therefore, we conclude that the dynamic stability is strongly dependent on the types of the LCs and voltage-dependent dynamics of the LC with negative dielectric anisotropy is staler than that of the LC with positive dielectric anisotropy in the FFS mode.

• Journal of Information Display
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• v.1 no.1
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• pp.9-13
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• 2000

In liquid crystal displays, the display mode that represents initial liquid crystal alignment and method of applying voltage, mainly determines the image quality of display. Recently we have developed the fringe-field switching (FFS) mode exhibiting high image quality. In this paper, a pixel concept, manufacturing process, materials, and electro-optic characteristics of the FFS mode comparing with conventional in-plane switching mode, and its possible application to reflective type are discussed.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.171-171
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• 2010

Electro-optic characteristics of liquid crystal display using fringe field switching(FFS) device depend on many parameters such as cell retardation, electrode structure, rubbing angle, cell gap and dielectric anisotropy. In this paper, the light efficiency of FFS mode will be analyzed to confirm the electro-optic characteristics according to positive dielectric anisotropy such as transmittance, operating voltage and response time.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.17 no.11
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• pp.1234-1240
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• 2004

We studied on the electro-optic characteristics and dynamic stability according to an undesirably defined pretilt angle induced in high step coverage of pixel area for the Twisted Nematic (TN) / Fringe-Field Switching (FFS) mode. In case of the TN mode, LC directors twist reversely near the edges of thin-film-transistor and black matrix where the pretilt angle of the LC is not well defined. Therefore, the voltage-dependent dynamics of the LC in TN mode is unstable and shows the bad electro-optic characteristics. On the other hand, in case of the FFS mode, the LCs are twisted parallel to the bottom substrate by fringe electric field and the electro-optic characteristic is not influenced by the pretilt angle of the LC which is not well defined.

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.621-624
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• 2006

Pixel structure of the fringe-field switching (FFS) mode to improve transmittance has been studied. New FFS structures related to the electrode structure at the edges of pixel, and the pixel electrode width and distance between electrodes was optimized. The former improves transmittance by minimizing the region of disclination lines. The latter improves it by increasing light efficiency above center of electrodes and also response time.