Ravenbrick LLC

The Programmable Matter Corporation

Brite-Line Technologies, LLC

Wil McCarthy

Richard M Powers

Gary E Snyder

Matthew Bryant Kish

Alex K Burney

Paul Ciszek

Neil Brian Cramer

Wounjhang Park

Andrew L LaFrate

Christopher M Caldwell

Michael Pitt

Coit Stevenson

Gordon Sill

Kevin H White

Robert Humphrey

Michael Pickford

Matthew B Kish

Andrew Lafrate

Thermochromic filters are constructed using absorptive, reflective, or fluorescent dyes, molecules, polymers, particles, rods, or other orientation-dependent colorants that have their orientation, order, or director influenced by carrier materials, which are themselves influenced by temperature. These order-influencing carrier materials include thermotropic liquid crystals, which provide orientation to dyes and polymers in a Guest-Host system in the liquid-crystalline state at lower temperatures, but do not provide such order in the isotropic state at higher temperatures. The varying degree to which the absorptive, reflective, or fluorescent particles interact with light in the two states can be exploited to make many varieties of thermochromic filters. Thermochromic filters can control the flow of light and radiant heat through selective reflection, transmission, absorption, and/or re-emission. The filters have particular application in passive or active light-regulating and temperature-regulating films, materials, and devices, and particularly as construction materials and building and vehicle surfaces.

Thermally switched optical filter incorporating a guest-host architecture

A pavement marking tape has raised, irregular polygonal relief features with retroreflective elements covering a portion of the surface of the tape. The form of the relief features minimizes shadowing effects. Raised relief features are shaped to increase the visible number of vertical faces and edges of the relief features, which are the most reflective structures, and are oriented toward incident light from an approaching observer to maximize retroreflectivity.

Pavement marking tape with widely-distributed, multi-edged relief features for improved retroreflectivity

A multifunctional building component is capable of serving as one or more of a window, a wall, a shading device, a roofing element, a color panel, a display, an energy harvesting device, an energy storage device, and an energy distribution device.

Multifunctional building component

Thermochromic liquid crystal filters are fabricated by providing two polarizers oriented at offset polarity with respect to each other; providing alignment structures adjacent the inner surfaces of the polarizers; placing a plurality of spacers between the polarizers; and filling a space created by the spacers with a thermotropic liquid crystal that acts as a wave block in an isotropic state and acts to rotate the polarization of light in a nematic state. Alternatively, the filters can be created by encapsulating a thermochromic liquid crystal with a polymer material to form a flexible film and orienting the thermochromic liquid crystal in the polymer material to create a structure that functions as a thermochromic optical filter. Such filters can control the flow of light and radiant heat through selective reflection, transmission, absorption, and/or re-emission. The filters have particular application in passive or active light-regulating and temperature-regulating films, materials, and devices, and particularly as construction materials.

Methods for fabricating thermochromic filters

An optical metapolarizer device polarizes light while mitigating the absorptive or reflective losses associated with traditional polarizers. The metapolarizer device transmits light of one polarity and rotates the other polarity so that it is closer to the transmitted polarity. As a result, although the light exiting the metapolarizer device is highly polarized, the total transmissivity of the device can be well in excess of 50%, and can approach 100% in the theoretical limit.

Optical metapolarizer device

A thermotropic optical shutter device incorporates coatable, thin-film polarizers with a thermotropic depolarizer. The coatable polarizers provide a mechanism for adjusting the polarizer properties (i.e., absorption, reflection, or diffusion) by changing the thickness of the coating. For example, a thicker film may have a higher relative polarizing efficiency while a thinner film may have a lower relative polarizing efficiency. Using the same base materials and manufacturing process, the contrast ratio and other properties of a thermotropic or thermochromic shutter device (e.g., a liquid crystal-based smart window film) may be adjusted in real time on the manufacturing line.

Thermotropic optical shutter incorporating coatable polarizers

A high-transparency, low-emissivity window film or coating is designed to maximize so-called greenhouse heating. This effect is achieved through the use of conductive grids and/or gratings whose width and spacing has been selected such that the grid appears as a uniform conductive film to long-wavelength infrared (blackbody) radiation. The conductive grid film reflects the blackbody radiation strongly, and such that the grid appears highly transparent to visible and near-infrared light, and therefore transmits it.

Low-emissivity window films and coatings incorporating nanoscale wire grids

Thermochromic filters use combinations of absorptive, reflective, thermoabsorptive, and thermoreflective elements covering different portions of the solar spectrum, to achieve different levels of energy savings, throw, shading, visible light transmission, and comfort. Embodiments include stopband filters in the near-infrared spectrum.

Thermochromic filters and stopband filters for use with same

A resizable polymer-stabilized, thermotropic liquid crystal device formulation is used in passive or active light-regulating and temperature-regulating films, materials and devices, including construction materials. Implementations of the device may be composed of five basic elements: one or more transparent substrates, a transparent surface treatment, a liquid crystal mixture, a stabilizing polymer, and spacer beads. The polymer-stabilized liquid crystal is coated and cured on at least one substrate. The transparent surface treatment and the stabilizing polymer network are selected to provide phase separation, curing, and adhesion within the LC mixture. The substrate or substrates may be polarizing or nonpolarizing.

Polymer stabilized thermotropic liquid crystal device

The thermally switched absorptive optical shutter may be a self-regulating 'switchable absorber' device that may absorb approximately 100% of incoming light above a threshold temperature, and may absorb approximately 50% of incoming light below a threshold temperature. The shutter may be formed by placing a thermotropic depolarizes between two absorptive polarizers. This control over the flow of radiant energy may occur independently of the thermal conductivity or insulation of the shutter device and may or may not preserve the image and color properties of incoming visible light. This has energy-efficiency implications as it can be used to regulate the internal temperature and illumination of buildings, vehicles, and other structures without the need for an external power supply or operator signals. The shutter device has unique optical properties that are not found in traditional windows, skylights, stained glass, light fixtures, glass blocks, bricks, or other building materials.

Thermally switched absorptive window shutter

The thermally switched reflective optical shutter is a self-regulating 'switchable mirror' device that reflects up to 100% of incident radiant energy above a threshold temperature, and reflects up to 50% of incident radiant energy below a threshold temperature. Control over the flow of radiant energy occurs independently of the thermal conductivity or insulating value of the device, and may or may not preserve the image and color properties of incoming visible light. The device can be used as a construction material to efficiently regulate the internal temperature and illumination of buildings, vehicles, and other structures without the need for an external power supply or operator signals. The device can be tailored to transmit sufficient visible light to see through in both the transparent and reflective states, while still providing significant control over the total energy transmission across the device.

Thermally switched reflective optical shutter

A multifunctional building component is capable of serving as one or more of a window, a wall, a shading device, a roofing element, a color panel, a display, and an energy harvesting, storage, and distribution element.

Thermochromic liquid crystal filters are fabricated by providing two polarizers oriented at offset polarity with respect to each other; providing alignment structures adjacent the inner surfaces of the polarizers; placing a plurality of spacers between the polarizers; and filling a space created by the spacers with a thermotropic liquid crystal that acts as a depolarizer in a nematic state. The filter acts as a wave block when the liquid crystal is in an isotropic state. Alternatively, the filters can be created by encapsulating a thermochromic liquid crystal with a polymer material to form a flexible film and orienting the thermochromic liquid crystal in the polymer material to create a structure that functions as a thermochromic optical filter. Such filters can control the flow of light and radiant heat through selective reflection, transmission, absorption, and/or re-emission. The filters have particular application in passive or active light-regulating and temperature-regulating films and materials.

A thermochromic, thermotropic, or thermoreflective filter relies on a mismatch between the index of refraction of a thermotropic material (e.g., a liquid crystal) and a substrate material that includes refractive or diffractive features. At colder operating temperatures, the refraction mismatches are eliminated or minimized such that the filter becomes transparent, whereas at high operating temperatures the refraction mismatches are increased such that for light at appropriate incidence angles, the structure becomes highly reflective. This filter has particular but not exclusive application as a temperature-controlled 'smart mirror' for use in windows, walls, roofing, and other building materials.

Thermally switched optical filter incorporating a refractive optical structure

The reflectivity and transmissivity of building and vehicle surfaces is maintained while employing partial, variable, selective, or asymmetric diffusers between a surface and an external light source such that the reflected light is diffused to produce a reduction in glare, while minimally effecting the specular or collimated transmission (if any) of light through the surface. Glare is also reduced by utilizing diffuser devices that reflect light in a temperature dependent manner.

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Lakewood, CO, United States of America

Wil McCarthy