Following the mature liquid crystals (LCs) display technology, there is a significant interest in implementing these devices into other non-display applications. Hence the emerging field of LC photonics is becoming increasingly active in which the strong electrooptic properties of LCs are harnessed for these applications particularly for imaging such as the use of SLMs, tunable focus lenses, tunable filters and polarization control devices. In this paper we review our recently developed LC devices integrated into full field optical coherence tomography system, into multi-spectral skin diagnosis system and in extended depth of focus imaging system.
A polarization independent Fabry–Perot liquid crystal tunable filter coupled to an optical fiber is demonstrated using polarization diversity. Using a Wollaston prism, the beam splits into two orthogonal beams, while the polarization of one of the beams is rotated by 90 deg using a variable half wave plate. The two beams are then combined into an optical fiber. Tuning of unpolarized light over the range 720 to 800 nm is demonstrated.