Polarized optical filtering from general linearly twisted structures

• Published in: Optics communications Vol. 267; no. 1; pp. 36 - 39
• Main Author: Abdulhalim, I.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01-11-2006; Elsevier Science
• Subjects: Anisotropic optical materials; Birefringence; Display devices, liquid-crystal devices; Exact sciences and technology; Filters; Filters, zone plates, and polarizers; Fundamental areas of phenomenology (including applications); Interference; Liquid crystals; Liquid-crystal devices; Optical elements, devices, and systems; Optical filters; Optical materials; Optics; Physics; Wave optics; Optical filters; Filters; Anisotropic optical materials; Liquid-crystal devices; Interference; Twist angle; Transfer functions; Theoretical study; Anisotropic material; Optical set up; Liquid crystals; Thin films; Wave plate; Birefringence; Liquid crystal devices; Birefringent plate; Optical materials
• ISSN: 0030-4018; 1873-0310
• DOI: 10.1016/j.optcom.2006.06.016

It is shown that a stack of linearly twisted birefringent plates with arbitrary successive twist angle acts as a spectral filter assuming the total twist equals an odd integer of π/2, and each plate acts as a full wave plate. The classical fan Solc filter is shown to be a very special case of the present concept. Based on this finding, spontaneously twisted structures analogous to the twisted liquid crystals and helical sculptured thin films can basically act as polarization filters if their molecular or nano-rod thickness and the local birefringence satisfy the full waveplate condition. Giving a certain number of full wave plates it is shown that there are many ways to arrange their successive twist and get the same transfer function.