Biomedical Optical Applications of Liquid Crystal Devices

Abstract

Liquid crystals exhibit large electro-optic effects which make them useful for a variety of applications as fast, compact, and tunable spectral filters, phase modulators, polarization controllers, and optical shutters. They were largely developed for liquid crystal displays and in the last decade for optical telecommunications, however their application in the field of optical imaging just started to emerge. These devices can be miniaturized thus have a great potential useful in miniature optical imaging systems for biomedical applications. Using a collection of tunable phase retarders one can perform: 1. Stokes parameters imaging for skin and eye polarimetric imaging; 2. Tunable filtering to be used for hyperspectral imaging, fluorescence microscopy, and frequency domain optical coherence tomography; 3. Adaptive optical imaging and eye aberrations correction; 4. Phase shift interferometric imaging; 5. Variable frequency structured illumination microscopy. Basic optics of liquid crystals devices is reviewed and some novel designs are presented in more detail when combined to imaging systems for a number of applications in biomedical imaging and sensing.

Design and Synthesis of Chiral Nematic Liquid Crystals

“…in a variety of ways, ranging from variation of temperature, stress, and electrical field, to variation of dopant concentration [56][57][58][59][60]. • Biomedical Applications -this is an emergent field for the use of liquid crystal devices for noninvasive biomedical imaging applications; this could include frequency domain optical tomography (FD-OCT), fluorescence imaging, aberration correction phase masks, birefringent filters, and polarographic imaging [61][62][63].…”

Optical manipulation for single‐cell studies

“…Much research is directed towards the development of specific fluorophores such as the green fluorescent protein (GFP) or quantum dots [60] and thanks to the progress within the field, fluorescence microscopy is currently experiencing a boom. Equally important is the development of sensitive and fast detectors to record signals from single molecules even at the picosecond level [64][65][66] as well as new filtering techniques in order to precisely sort out minute energy differences [67][68][69][70]. Widely used fluorescent techniques include wide-field fluorescence microscopy, confocal laser scanning microscopy and multiphoton microscopy.…”

QSPR Analysis of a Set of Liquid Crystals in the Benzylideneaniline Class According to their Transition Temperature

“…The molecular structure is a defining criterion in the categorization of mesophases as anisotropic liquids or liquid crystals [6]. a rapidly and directly through their color [19]. In chemistry, nematic and cholesteric liquid crystals are very good solvents for organic molecules.…”