Abstract: A thermochromic optical filter incorporating quantum confinement devices is formed as multilayered composite film of semiconducting materials. A quantum well adjacent a barrier layer ensures proper confinement of charge carriers within the well. A transition wavelength (i.e., the energy/wavelength at which the filter becomes transparent) is established by selecting a quantum well material with a bandgap near the desired energy and a barrier layer material with a higher bandgap. For a given reference temperature (e.g., room temperature), the exact transition wavelength is fixed by the thickness of the quantum well. The quantum confinement energy is added to the bandgap energy to yield the transition energy. A thermal control system varies the temperature of the thermochromic filter to adjust the transition wavelength. Temperature changes affect both the bandgap and the quantum confinement energy, and thus the optical properties of the thermochromic filter.

Abstract: 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.

Abstract: A wavelength-specific optical switch combines one or more tunable filters and bandblock reflectors such that the absorption or reflection of selected wavelength bands in the optical spectrum (visible, near infrared, or near ultraviolet) can be switched on and off. The wavelength switch is programmable, multifunctional, general-purpose, solid-state optical filter. The wavelength switch may serve as a tunable notch or bandblock filter, a tunable bandpass filter, a tunable highpass or lowpass filter, or a tunable band reflector. The wavelength switch has particular, but not exclusive, application in optics as a filter, band reflector, and as a means of isolating particular wavelengths or wavelength bands from a collimated light stream for transmission to, or rejection from, a sensor.

Abstract: 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.

Abstract: A thermally switched optical downconverting (TSOD) filter is a self-regulating device including a downconverter that converts incoming light at a variety of wavelengths into longer-wavelength radiation and then directs it using one or more bandblock filters in either the inward or outward direction, depending on the temperature of the device. This control over the flow of radiant energy occurs independently of the thermal conductivity or insulating properties of the device and may or may not preserve the image and color properties of incoming visible light. The TSOD filter is energy-efficient 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 TSOD filter has unique aesthetic and optical properties not found in traditional windows, skylights, stained glass, light fixtures, glass blocks, bricks, or walls.

Abstract: 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 has unique aesthetic optical properties that are not found in traditional windows, skylights, stained glass, light fixtures, glass blocks, bricks, or walls.

Abstract: 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.

Abstract: 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.

Abstract: A thermally switched optical downconverting (TSOD) filter is a self-regulating device including a downconverter that converts incoming light at a variety of wavelengths into longer-wavelength radiation and then directs it using one or more bandblock filters in either the inward or outward direction, depending on the temperature of the device. This control over the flow of radiant energy occurs independently of the thermal conductivity or insulating properties of the device and may or may not preserve the image and color properties of incoming visible light. The TSOD filter 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 TSOD filter also has aesthetic implications, since the device has unique optical properties that are not found in traditional windows, skylights, stained glass, light fixtures, glass blocks, bricks, or walls.

Abstract: 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 has unique aesthetic optical properties that are not found in traditional windows, skylights, stained glass, light fixtures, glass blocks, bricks, or walls.

Abstract: Quantum dots are positioned within a layered composite film to produce a plurality of real-time programmable dopants within the film. Charge carriers are driven into the quantum dots by energy in connected control paths. The charge carriers are trapped in the quantum dots through quantum confinement, such that the charge carriers form artificial atoms, which serve as dopants for the surrounding materials. The atomic number of each artificial atom is adjusted through precise variations in the voltage across the quantum dot that confines it. The change in atomic number alters the doping characteristics of the artificial atoms. The layered composite film is also configured as a shift register.

Abstract: 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 as a depolarizer 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.

Abstract: Quantum dots are positioned within a layered composite film to produce one-dimensional and multi-dimensional shift registers within the film. Charge carriers are driven into the quantum dots by energy in connected control paths. The charge carriers are trapped in the quantum dots through quantum confinement, such that the charge carriers form artificial atoms, which serve as dopants for the surrounding materials. The atomic number of each artificial atom is adjusted through precise variations in the voltage across the quantum dot that confines it. The position of the artificial atom in the film is moved by varying the location of confinement and thus operates as a shift register.

Abstract: A thermochromic optical filter incorporating quantum confinement devices is formed as multilayered composite film of semiconducting materials. A quantum well adjacent a barrier layer ensures proper confinement of charge carriers within the well. A transition wavelength (i.e., the energy/wavelength at which the filter becomes transparent) is established by selecting a quantum well material with a bandgap near the desired energy and a barrier layer material with a higher bandgap. For a given reference temperature (e.g., room temperature), the exact transition wavelength is fixed by the thickness of the quantum well. The quantum confinement energy is added to the bandgap energy to yield the transition energy. A thermal control system varies the temperature of the thermochromic filter to adjust the transition wavelength. Temperature changes affect both the bandgap and the quantum confinement energy, and thus the optical properties of the thermochromic filter.

Abstract: A programmable dopant fiber includes a plurality of quantum structures formed on a fiber-shaped substrate, wherein the substrate includes one or more energy-carrying control paths, which pass energy to quantum structures. Quantum structures may include quantum dot particles on the surface of the fiber or electrodes on top of barrier layers and a transport layer, which form quantum dot devices. The energy passing through the control paths drives charge carriers into the quantum dots, leading to the formation of “artificial atoms” with real-time, tunable properties. These artificial atoms then serve as programmable dopants, which alter the behavior of surrounding materials. The fiber can be used as a programmable dopant inside bulk materials, as a building block for new materials with unique properties, or as a substitute for quantum dots or quantum wires in certain applications.

Abstract: An insulating glass unit (IGU) is used for storing and transporting thermoreflective filters or other thin, fragile devices, chiefly because such filters are often fragile and heavy. Because the IGU may also be the functional enclosure for the thermoreflective filter when it is installed in a building, using the IGU as a shipping container minimizes the total handling of the unpackaged filter and therefore minimizes the risk of damage or breakage.

Abstract: 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.

Abstract: A multispectral optical sensor incorporating quantum confinement devices is composed of a solid-state tunable filter, an optional lens, and a photodetector or plurality of photodetectors. The tunable filter is multilayered composite film of semiconducting materials, which includes a quantum well or other quantum confinement structure and barrier materials to ensure the proper confinement of charge carriers within the quantum well. The tunable filter is capable of acting as a long-pass filter. The approximate cut-on wavelength is established through selection of a well material with a bandgap near the desired energy, and barrier materials with a higher bandgap. For a given reference temperature the exact cut-on wavelength may be fixed through careful selection of the dimensions of the quantum confinement structures, whose quantum confinement energy is added to the bandgap energy to yield the cut-on energy.

Abstract: 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 depolarizer 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. It also has aesthetic implications since the shutter device has unique optical properties that are not found in traditional windows, skylights, stained glass, light fixtures, glass blocks, bricks, or walls.

Abstract: 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.