Light Transmission Experiments with Nematic Liquid Crystals Showing Positive and Negative Dielectric Anisotropy
- 1 January 1977
- journal article
- research article
- Published by Taylor & Francis in Molecular Crystals and Liquid Crystals
- Vol. 38 (1) , 77-85
- https://doi.org/10.1080/15421407708084376
Abstract
We report on the light transmission of nematic liquid crystals with positive and negative dielectric anisotropy under a.c. electric fields. Using the twisted nematic effect we determined the frequency of dielectric isotropy f 0 as a function of temperature for the phenyl benzoates mixtures ZLI 518, WI and ZLI 612 (Fa. E. Merck). The results are in good agreement with those from dielectric measurements. The activation energies for this relaxation process were calculated. By tunable birefringence the temperature dependence of the refractive index difference was measured for 4′-n-pentyl-4-cyanobiphenyl (PCB). The results were compared with those from measurements with the Leitz-Jelly micro-refractometer.Keywords
This publication has 8 references indexed in Scilit:
- Determination of the frequency of dielectric isotropy as a function of temperature by light transmission measurementsPhysics Letters A, 1976
- Fast-switching twisted nematic electro-optical shutter and colour filterElectronics Letters, 1974
- Electric Field Induced Deformation in Nematic Phenyl BenzoatesPublished by Springer Nature ,1974
- Nematic Phenyl Benzoates in Electric Fields: I. Static and Dynamic Properties of the Dielectric PermittivityMolecular Crystals and Liquid Crystals, 1974
- Controlled decay of electrically induced deformations in nematic liquid crystalsApplied Physics A, 1973
- Optics Experiments with Nematic Liquid CrystalsAmerican Journal of Physics, 1973
- Electrically Controlled Birefringence of Thin Nematic FilmsJournal of Applied Physics, 1972
- VOLTAGE-DEPENDENT OPTICAL ACTIVITY OF A TWISTED NEMATIC LIQUID CRYSTALApplied Physics Letters, 1971