US 9,869,887 B2 · Adaptive liquid crystal structural interface

Abstract

A structural interface having an adaptive liquid crystal material that is positioned to receive electromagnetic radiation and adapted to reflect a selective band of the received electromagnetic radiation so as to help with cooling of a structure in the summer and/or heating of the structure in the winter. The adaptive liquid crystal material is designed to change its selective reflection band when exposed to an activating temperature or an activating light or both. Depending on the interior and/or exterior conditions, the adaptive liquid crystal material has one or more selective reflection bands with a peak wavelength selected from the following: within a sunlight wavelength span, outside a thermal infrared wavelength span, outside the sunlight wavelength span, or within the thermal infrared wavelength span. The structural interface may be applied to an exterior or interior surface of a structural envelop or be integrated into a structural envelope material.

Claims26

Dependent claims

A structural interface comprising an adaptive cholesteric liquid crystal material positioned to receive electromagnetic radiation and adapted to reflect a selective band of said electromagnetic radiation;

wherein the adaptive cholesteric liquid crystal material undergoes a reversible photo-induced or thermal induced change in chirality or both such that it reversibly changes its pitch and thereby its selective reflection band when exposed to an activating temperature or an activating light or both without undergoing phase transition,
wherein the cholesteric liquid crystal material comprises a chiral dopant having a helical twisting power, and wherein said helical twisting power changes by 20% or more when exposed to a temperature change of 10° C. or greater, or when exposed to said activating light, or both, and
wherein the adaptive cholesteric liquid crystal material has one or more selective reflection bands with a peak wavelength (λmax) selected from:
within 400-1000 nm during hot conditions and outside 400-1000 nm during cold conditions;
or
within 3000-10,000 nm during cold conditions and outside 3000-10,000 nm during hot conditions.

3 more elements

Dependencies are inferred from the claim text.

Adaptive liquid crystal structural interface

Life of this patent

Adaptive liquid crystal structural interface

Life of this patent

Abstract

Claims26