Production of arbitrary polarized light beams with a liquid crystal spatial modulator

2016 ◽  
Author(s):  
Ignacio Moreno ◽  
Maria M. Sánchez-López ◽  
Jeffrey A. Davis ◽  
Katherine Badham ◽  
Don M. Cottrell
Keyword(s):  
Liquid Crystal ◽  
Polarized Light ◽  
Light Beams

ELECTRO-OPTICAL EFFECT IN COMPOSITE PHOTONIC STRUCTURES BASED ON GROOVED SILICON AND LIQUID CRYSTAL

2007 ◽  
Vol 06 (03n04) ◽  
pp. 179-185
Author(s):  
E. V. ASTROVA ◽  
YU. A. PILYUGINA ◽  
T. S. PEROVA ◽  
S. A. GRUDINKIN
Keyword(s):  
Liquid Crystal ◽  
Periodic Structures ◽  
Spectral Response ◽  
Polarized Light ◽  
Silicon On Insulator ◽  
Planar Waveguides ◽  
Optical Effect ◽  
Electro Optical Effect ◽  
Wet Anisotropic Etching ◽  
Light Beams

One-dimensional periodic structures with deep vertical grooves were obtained by wet anisotropic etching of (110)-oriented silicon-on-insulator (SOI) structure. Grooves of various widths (4–16 μm) were filled with a nematic liquid crystal (LC) E7. Inter-digital configuration of silicon electrodes was used to apply a voltage which altered the refractive index of the liquid crystal. Reproducible Freedericksz effect with a threshold voltage from 2 to 3 V was registered visually in the polarized light of a microscope and studied by means of micro-Raman spectroscopy. The electro-optical effect in the structures can be used to tune the band gaps of 1D photonic crystals, the spectral response of microcavities and to steer light beams in high contrast planar waveguides and waveguide arrays.

scholarly journals Design and Realization of a Compact Efficient Beam Combiner, Based on Liquid Crystal Pancharatnam–Berry Phase Gratings

Crystals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 220
Author(s):  
Boxuan Gao ◽  
Jeroen Beeckman ◽  
Kristiaan Neyts
Keyword(s):  
Liquid Crystal ◽  
Berry Phase ◽  
Polarized Light ◽  
Laser Beams ◽  
Circularly Polarized Light ◽  
Circularly Polarized ◽  
Beam Combiner ◽  
High Diffraction Efficiency ◽  
High Diffraction ◽  
Crystal Mixture

We demonstrate a laser beam combiner based on four photo-patterned Pancharatnam–Berry (PB) phase gratings, which is compact and has high diffraction efficiency for incident circularly polarized light. The nematic liquid crystal mixture E7 is used as anisotropic material, and the thickness of the layer is controlled by spacers. The beam combiner can bring two parallel laser beams closer to each other while remaining parallel. This work shows the potential to realize components based on flat optical LC devices.

Lamellar Lyotropic Liquid Crystal Phases as a Carrier for Skin Delivery of Morus alba Stem Extract

2021 ◽  
Vol 901 ◽  
pp. 67-72
Author(s):  
Chein Yhirayha ◽  
Sakchai Wittaya-Areekul ◽  
Tasana Pitaksuteepong
Keyword(s):  
Liquid Crystal ◽  
Biological Activities ◽  
Polarized Light ◽  
Water Extract ◽  
Skin Penetration ◽  
Morus Alba ◽  
Lyotropic Liquid Crystal ◽  
Mixed Surfactant ◽  
Skin Delivery ◽  
Stem Extract

Morus alba stem extract possesses several biological activities. However, skin delivery of the extract is limited by the stratum corneum. In this study, lamellar lyotropic liquid crystal (LLC) was investigated for the potential application in the skin delivery of M. alba stem extract. The four formulations were developed and incorporated with M. alba stem extract at 3% w/w. These formulations were stored at room temperature in light-protected containers for 3 months. The optical pattern under polarized light microscope, viscosity and remaining of the extract were determined. The skin penetration enhancing property of the formulations was investigated using excised porcine ear skin model. The results showed that all formulations remained stable after 3-month storage. The two formulations exhibiting good penetration enhancing properties were F3 consisting of PEG-7 glyceryl cocoate/n-Dodecane/Water/extract (55.29/19.40/22.31/3.00 %w/w) and F4 consisting of mixed Surfactant/n-Dodecane/Water/extract (48.50/4.85/43.65/3.00 %w/w). The mixed surfactant composed of PEG-7 glyceryl cocoate/PEG-40 hydrogenated castor oil/Glyceryl oleate (40/33.24/26.76 %w/w). It can be concluded that the lamellar LLC formulations developed in this study can be used as a carrier for delivering of M. alba stem extract. The components of the formulations which play important roles are the oil and the surfactant.

scholarly journals Radially polarized light beams from spin-forbidden dark excitons and trions in monolayer WSe2

2020 ◽  
Vol 10 (5) ◽  
pp. 1273
Author(s):  
Sven Borghardt ◽  
Jens Sonntag ◽  
Jhih-Sian Tu ◽  
Takashi Taniguchi ◽  
Kenji Watanabe ◽  
...  
Keyword(s):  
Polarized Light ◽  
Light Beams ◽  
Radially Polarized ◽  
Radially Polarized Light

scholarly journals Vortices Nucleation By Inherent Fluctuations In Nematic Liquid Crystal Cells

2021 ◽  
Author(s):  
Esteban Aguilera ◽  
Marcel G. Clerc ◽  
Valeska Zambra
Keyword(s):  
Liquid Crystal ◽  
Optical Tweezers ◽  
Nematic Liquid Crystal ◽  
Topological Defects ◽  
Optical Vortices ◽  
Topological Features ◽  
Nucleation Mechanisms ◽  
Multistable Systems ◽  
Light Beams ◽  
Crystal Cells

Abstract Multistable systems are characterized by exhibiting domain coexistence, where each domain accounts for the different states. In the case of these systems are described by vectorial fields, domains are connected through topological defects. Vortices are one of the most frequent and studied topological defect points. Optical vortices are equally relevant for their fundamental features as beams with topological features and their applications in image processing, telecommunications, optical tweezers, and quantum information. The interaction of light beams with matter vortices in liquid crystal cells is a natural source of optical vortices. The rhythms that govern the emergence of matter vortexes due to fluctuations are not established. Here we investigate the nucleation mechanisms of the matter vortices in liquid crystal cells and establish statistical laws that govern them. Based on a stochastic amplitude equation, the law for the number of nucleated vortices as a function of anisotropy, voltage, and noise level intensity is set. Experimental observations in a nematic liquid crystal cell with homeotropic anchoring and a negative anisotropic dielectric constant under the influence of a transversal electric field show a fair agreement with the theoretical findings.

scholarly journals Kinetochore-driven outgrowth of microtubules is a central contributor to kinetochore fiber maturation in crane-fly spermatocytes

2014 ◽  
Vol 25 (9) ◽  
pp. 1437-1445 ◽  
Author(s):  
James R. LaFountain ◽  
Rudolf Oldenbourg
Keyword(s):  
Liquid Crystal ◽  
Life Histories ◽  
Polarized Light ◽  
Fiber Formation ◽  
Image Brightness ◽  
Early Stages ◽  
Anaphase Onset ◽  
Bipolar Spindles ◽  
Polarized Light Imaging

We use liquid crystal polarized light imaging to record the life histories of single kinetochore (K-) fibers in living crane-fly spermatocytes, from their origins as nascent K-fibers in early prometaphase to their fully matured form at metaphase, just before anaphase onset. Increased image brightness due to increased retardance reveals where microtubules are added during K-fiber formation. Analysis of experimentally generated bipolar spindles with only one centrosome, as well as of regular, bicentrosomal spindles, reveals that microtubule addition occurs at the kinetochore-proximal ends of K-fibers, and added polymer expands poleward, giving rise to the robust K-fibers of metaphase cells. These results are not compatible with a model for K-fiber formation in which microtubules are added to nascent fibers solely by repetitive “search and capture” of centrosomal microtubule plus ends. Our interpretation is that capture of centrosomal microtubules—when deployed—is limited to early stages in establishment of nascent K-fibers, which then mature through kinetochore-driven outgrowth. When kinetochore capture of centrosomal microtubules is not used, the polar ends of K-fibers grow outward from their kinetochores and usually converge to make a centrosome-free pole.

scholarly journals Impact of the Liquid Crystal Director Twisting on Two-Beam Energy Exchange in a Hybrid Photorefractive Inorganic-Liquid Crystal Cell

Crystals ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1104
Author(s):  
Victor Yu. Reshetnyak ◽  
Igor P. Pinkevych ◽  
Michael E. McConney ◽  
Jonathan E. Slagle ◽  
Dean R. Evans
Keyword(s):  
Liquid Crystal ◽  
Beam Energy ◽  
Energy Exchange ◽  
Gain Coefficient ◽  
Liquid Crystal Cell ◽  
Helix Pitch ◽  
Propagation Of Light ◽  
Light Waves ◽  
Light Beams ◽  
Grating Spacing

We studied the energy transfer between light beams on the director grating in a hybrid photorefractive liquid crystal (LC) cell assuming the propagation of light waves in the cell to be in the Mauguin regime. This approach makes it possible to trace the change of the gain coefficient dependence on the director grating spacing with the change of the LC director twist. Conditions for the LC flexoelectric parameters and the director helix pitch necessary for transformation the gain coefficient dependence from the nematic to cholesteric type are obtained. The influence of the director splay and bend deformations on the gain coefficient is also studied.

scholarly journals Mesomorphism behaviour and photoluminescent properties of new asymmetrical 1,2-di(4-alkoxybenzylidene)hydrazines

2019 ◽  
Vol 43 (1-2) ◽  
pp. 67-77 ◽  
Author(s):  
Adil A Awad ◽  
Al-Ameen Bariz OmarAli ◽  
Ahmed Jasim M Al-Karawi ◽  
Zyad Hussein J Al-Qaisi ◽  
Samer Ghanim Majeed
Keyword(s):  
Differential Scanning Calorimetry ◽  
Liquid Crystal ◽  
Liquid Crystalline ◽  
Polarized Light ◽  
Luminescent Properties ◽  
Scanning Calorimetry ◽  
Crystalline Materials ◽  
X Ray ◽  
Step Procedure ◽  
Liquid Crystalline Materials

{1-[4-( n-Alkoxy)]-2-(4’-decyloxy)benzylidene}hydrazines ( n-alkoxy = O(CH2) nH, n = 1–9, 12, 16 or 18), an asymmetrical series of 1,2-disubstituted hydrazines, were prepared in a simple two-step procedure as a part of our continuing work in evaluating hydrophobic azine compounds as photoluminescent liquid crystalline materials. The compounds were characterized spectroscopically and their liquid crystalline behaviour and luminescent properties were evaluated using polarized light optical microscopy, differential scanning calorimetry and X-ray powder diffraction techniques. The studies revealed that all of these compounds are liquid crystalline materials exhibiting photoluminescent properties in the crystalline and liquid crystal states.

Sign in / Sign up

Export Citation Format

Share Document