The presently disclosed subject matter relates to electromechanical systems and devices, and more particularly to electromechanical systems for implementing reflective devices for displays, sensors, and authentication solutions. In some embodiments a reflective device includes a thin film transistor layer and a plurality of reflective elements positioned approximately parallel to the thin film transistor layer. The plurality of reflective elements is electrically coupled with the thin film transistor layer. Each reflective element is configured for controlling a reflectance parameter of the reflective element based on a first voltage applied to the reflective element by the thin film transistor. In other embodiments, a reflective element includes a transparent substrate and a plurality of polymer-air pair layers positioned approximately parallel position to the transparent substrate. The plurality of polymer-air pair layers are configured to vary a reflectance parameter based on a force applied to the plurality of polymer-air pair layers.

A method for assembling an electro-optic mirror reflective element for a vehicular rearview mirror assembly includes providing a container having a plurality of holes for dispensing spacer beads, supporting the container over a dispensing area via an electrically powered shaking device, positioning a glass substrate at the dispensing area, and automatically shaking the container so that spacer beads fall through the holes in the container and onto the glass substrate. The shaking of the container is controlled so that the shaking device is deactivated after an appropriate amount of spacer beads are dispensed onto the glass substrate. The glass substrate is mated with another glass substrate with the dispensed spacer beads between the glass substrates and bounded by a perimeter seal. The cavity between the glass substrates is filled with an electro-optic medium, and the cavity is sealed with the electro-optic medium and spacer beads disposed therein.

An optical stack including an oriented polymeric multilayer optical film and a non-birefringent optical filter is described. The oriented polymeric multilayer optical film has a first reflection band with a first band edge and the non-birefringent optical filter has a first blocking band. In some cases, the first blocking band contains the first band edge and the first blocking band provides a reduction in variation of a band edge of an overall blocking band of the optical stack.

Provided are a cholesteric liquid crystal layer having an excellent reflection anisotropy, a low haze, and a high circular polarization degree of reflected light, and a method for producing the same. In addition, provided are a laminate, an optically anisotropic body, and a reflective film, each of which including the cholesteric liquid crystal layer. A cholesteric liquid crystal layer formed using a liquid crystal compound, in which, in at least one main plane out of a pair of main planes of the cholesteric liquid crystal layer, a direction of a molecular axis of the liquid crystal compound changes while continually rotating along at least one in-plane direction, the molecular axis of the liquid crystal compound is tilted with respect to the main plane of the cholesteric liquid crystal layer, and an arrangement direction of bright portions and dark portions derived from the cholesteric liquid crystalline phase, as observed under a scanning electron microscope in a cross section perpendicular to the main plane, is tilted with respect to the main plane of the cholesteric liquid crystal layer.

Various embodiments disclosed relate to multilayer films including hidden fluorescent features. The present disclosure includes a multilayer optical film including an isotropic multilayer optical film having first and second opposed major surfaces. The isotropic multilayer optical film reflects at least 50% of a light that is at least one of ultraviolet light or visible light, having an incident angle less than a cutoff angle from normal to the first major surface of the isotropic multilayer optical film, wherein the cutoff angle is in a range from 10 to 70. The isotropic multilayer optical film allows at least 50% of the light having an incident angle of more than the cutoff angle from normal to the first major surface of the isotropic multilayer optical film to pass through the isotropic multilayer optical film. The isotropic multilayer optical film includes a marking on the second major surface of the isotropic multilayer optical film, the marking including at least one fluorescent compound. Various embodiments of multilayer optical films described herein are useful, for example, as anti-counterfeiting features, such as in identification documents or cards, currency, labels for pharmaceuticals or other high value products, or financial cards.

Fully artificial, adaptive composite materials and systems, having variable transmittance, reflectance, and/or absorptance to radiation in visible, infrared, or other desired region of the electromagnetic spectrum, and methods of the manufacture and use thereof are provided. The adaptive composite materials and systems possess an unprecedented combination of properties and are, therefore, poised to enable a broad range of practical applications. The adaptive composite material incorporates at least one size-variable active area having a variable transmittance, reflectance, and/or absorptance in at least a portion of the electromagnetic spectrum and comprises at least: an elastomer substrate, a texturizing layer disposed on top of the substrate, and an optional reflective coating disposed on top of the texturizing layer. In operation, the stretching and relaxation of the elastomer substrate causes changes in the surface morphology of the texturized layers (e.g., the change in the size and depth of surface features in the texturizing layer), this in turn results in the increased or decreased transmittivity, reflectivity, and/or absorptivity of the active area.

Techniques disclosed herein relate to modifying refractive index modulation in a holographic optical element, such as a holographic grating. According to certain embodiments, a holographic optical element or apodized grating includes a polymer layer comprising a first region characterized by a first refractive index and a second region characterized by a second refractive index. The holographic optical element or apodized grating includes a plurality of nanoparticles dispersed in the polymer layer. The nanoparticles have a higher concentration in either the first region or the second region. In some embodiments, the nanoparticles may be configured to increase the refractive index modulation. In some embodiments, the nanoparticles may be configured to apodize the grating by decreasing the refractive index modulation proximate to sides of the grating. The refractive index may be modulated by applying a monomer reservoir buffer layer to the polymer layer, either before or after hologram fabrication.

An optical reflection film may include an optical interference film formed by alternately laminating a high refractive index layer and a low refractive index layer with a refractive index difference therebetween on a substrate. Among the high refractive index layers and the low refractive index layers constituting the optical interference film, if a layer disposed closest to the substrate is defined as a lowermost layer, a layer farthest from the substrate is defined as an uppermost layer, and each of layers disposed between the lowermost layer and the uppermost layer is defined as an intermediate layer, the average elastic modulus of the intermediate layers measured by a nano-indentation method is higher than the elastic modulus of the uppermost layer by 2 GPa or more, and the film thickness of the uppermost layer is 1.2 to 7 times the average film thickness of the intermediate layers.

A passive cooling article is disposed on a substrate to cool the substrate. The article includes an outer layer having a high absorbance in the atmospheric window region of the electromagnetic spectrum and having a high transmittance in the solar region of the spectrum. The article also includes a reflector having a high reflectivity in the solar region of the spectrum. At least one of the outer layer and the reflector includes a fluoropolymer. Micro-sized particles or surface structures may be disposed in or on the outer layer or the reflector to improve absorbance. A metallic layer may be disposed between the fluoropolymer and the substrate to be cooled.

Solar energy device comprising at least one of a photovoltaic cell or a solar thermal collector having an absorption bandwidth in the infrared wavelength region of the solar spectrum; a visible light-transmitting reflector; and at least one of a graphic film or lighted display. The graphic film or a lighted display present is visible through the visible light-transmitting reflector. The solar energy devices can be used, for example, as a sign (e.g., an advertising sign or a traffic sign), on the side and/or roof, as well as in a window, of a building.