УДК: 532.783, 535.771, 535.36

Spectral characteristics of tunable IR liquid-crystal filters based on the Christiansen effect

Publication in Journal of Optical Technology

For Russian citation (Opticheskii Zhurnal):

Дик В.П., Лойко В.А. Спектральные характеристики инфракрасных перестраиваемых жидкокристаллических фильтров, основанных на эффекте Христиансена // Оптический журнал. 2015. Т. 82. № 9. С. 34–40.

Dik V.P., Loiko V.A. Spectral characteristics of tunable IR liquid-crystal filters based on the Christiansen effect [in Russian] // Opticheskii Zhurnal. 2015. V. 82. № 9. P. 34–40.

For citation (Journal of Optical Technology):

V. P. Dik and V. A. Loĭko, "Spectral characteristics of tunable IR liquid-crystal filters based on the Christiansen effect," Journal of Optical Technology. 82(9), 602-606 (2015). https://doi.org/10.1364/JOT.82.000602

Abstract:

This paper discusses electrically controllable IR dispersion filters based on a small-particles–liquid-crystal system. A calculational technique is presented, and the connection of the structural parameters of the filters and their spectral characteristics is analyzed, using as an example a system composed of aluminum oxide particles and the liquid crystal 4-methoxybenzylidene-4^′-butylaniline. It is shown that the transmission bandwidth is minimized under the following conditions: the particle size is a factor of 4–6 greater than the wavelength corresponding to the maximum transmittance of the filter; the volume concentration of particles lies in the interval 0.5–0.6; the ratio of the half-width of the distribution to the modal radius does not exceed 0.2; and the filter thickness is a factor of 15–20 greater than the mean particle size.

Keywords:

liquid crystals, light scattering, dispersion filters

Acknowledgements:

This work was carried out with the support of the Belarusan Republic Foundation for Basic Research.

OCIS codes: 230.3720, 160.3710

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