Optical UV Dosimeters Based on Photoracemization of (R)‐(+)‐1,1′‐Bi(2‐Napthol) (BINOL) within a Chiral Nematic Liquid Crystalline Matrix

Abstract

Accurate and low-cost wearable or portable monitors for personal solar ultraviolet (UV) exposure are of interest to reduce the risk of adverse UV effects such as eye diseases, sunburn and skin cancer. Here, a novel sensor involving the racemization of a chiral dopant within a nematic liquid crystalline matrix is described, and the suitability of these sensors to act as personal UV dosimeters is explored. It was shown that these sensors respond to UV light with a significant change in the position of the reflection band of the chiral nematic liquid crystal. The sensitivity of these sensors is shown to be 0.23 nm/mJcm À 2 . This corresponds to a change of 80 nm over a dose equivalent to two hours of solar exposure.

Machine learning methods for liquid crystal research: phases, textures, defects and physical properties

“…98,99 Liquid crystals are also used in thermography for mapping of temperature and turbulent streaks, [100][101][102] X-ray radiation detection 103 and sunlight ultraviolet. [104][105][106] In a recent study, ML algorithm has been applied to the shear-sensitive liquid crystal coating (SSLCC) used for nonintrusive global wall shear stress measurements. 107 A feedforward back-propagation network predicted the magnitude and direction of shear by mapping the relationship between the SSLCC colors observed at different viewing angles and the corresponding wall shear stress vectors.…”

“…98,99 Liquid crystals are also used in thermography for mapping of temperature and turbulent streaks, 100–102 X-ray radiation detection 103 and sunlight ultraviolet. 104–106…”

Optical Indicators based on Structural Colored Polymers

“…An interesting application is demonstrated by a nonpolymerized structural color UV indicator able to monitor the exposure to harmful sunlight. [ 70 ] Implementation in an optical integrator can result in a mechanical deformation as a response to light. For light‐responsive integrators, further control of the time factor is possible as the response for a specific photoswitch molecule is dependent on an isomerization equilibrium.…”