Investigations of twist elastic constant K₂₂ of new nematic liquid crystal materials using threshold IPS method

• Autorzy: Parka J. , Dąbrowski M. , Kowerdziej R.
• Języki publikacji: EN

Abstrakty

EN

The liquid crystal technology is one of the most popular at the present time. To the most important parameters of liquid crystals belong optical anisotropy, viscosity, and twist elastic constants. One of the most difficult and problematic to measure parameters is a twist elastic constant K₂₂. For new liquid crystalline materials, we have to characterize their physical properties, also a twist elastic constant K₂₂. As a final result of this work, a twist elastic constant of new nematic liquid crystal materials was investigated. In this paper, a transmission-voltage characteristic of the in-plane switching cell was observed to find Freedericksz threshold, and then twist elastic constants could have been calculated. The method was checked on well-characterized materials E7 and 6-CHBT and its accuracy was better than 20%. In addition, the temperature dependence of K₂₂ was determined for all materials.

Słowa kluczowe

EN

liquid crystals; nematic; twist elastic constant; in-plane switching

• Wydawca: Stowarzyszenie Elektryków Polskich ; Polska Akademia Nauk ; Wojskowa Akademia Techniczna im. Jarosława Dąbrowskiego
• Czasopismo: Opto-Electronics Review
• Rocznik: 2011
• Tom: Vol. 19, No. 1
• Strony: 114--118
• Opis fizyczny: Bibliogr. 19 poz., il., wykr.

Twórcy

autor

Parka J.

autor

Dąbrowski M.

autor

Kowerdziej R.

• Institute of Applied Physics, Military University of Technology, 2 Kaliskiego Str., 00-908 Warsaw, Poland

Bibliografia

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