Electro-Optical and Photo Stabilization Study of Nematic Ternary Mixture

• Main Authors: Aleksandra Kalbarczyk, Noureddine Bennis, Jakub Herman, Leszek R. Jaroszewicz, Przemysław Kula
• Format: Article
• Language: English
• Published: MDPI AG 2021-04-01
• Series: Materials
• Subjects: frequency-controlled birefringence; photostability; response time
• Online Access: https://www.mdpi.com/1996-1944/14/9/2283

Liquid crystal materials composed of mixed nematic compounds find broad use in liquid crystal displays and photonic applications. A ternary mixture formed from three different nematic compounds shows peculiar behavior such as tunable electro-optical properties dependent on the frequency of the driving voltage. The paper presents an analysis of the response time and phase retardation of a frequency tunable nematic liquid crystal mixture (under code name 5005). This material possesses high birefringence (Δ<i>n</i> = 0.32 at 633 nm) as well as high dielectric anisotropy (Δ<i>ε</i> = 6.3 at 100 Hz). The unique property of the 5005 mixture is frequency-controlled phase modulation, as in a dual frequency liquid crystal, while dielectric anisotropy goes to zero instead of being negative at high frequencies. For each component of the mixture, details on mesomorphic properties and their role in the formulation of the mixture are reported. The 5005 mixture was characterized by multiple investigation techniques, such as temperature dependence dielectric anisotropy, transmittance measurements image polarizing microscopy, and UV stability.