Abstract: In some examples, a system includes: at least one light capture device; an article of personal protective equipment (PPE) that includes a plurality of retroreflective elements embodied on a surface of the article of PPE in a spatially defined arrangement, each retroreflective element of the plurality of retroreflective elements having at least two different retroreflective properties; a computing device communicatively coupled to the at least one light capture device, wherein the computing device is configured to: receive, from the at least one light capture device, retroreflected light that indicates at least two different retroreflective properties of at least one retroreflective element of the plurality of retroreflective elements; determine, based at least in part on each of the at least two different retroreflective properties, a safety event; and perform at least one operation based at least in part on the safety event.

Abstract: An optical stack (100) includes an optical diffuser (10) and a first reflective polarizer (40) disposed on the optical diffuser (10). For substantially normally incident light and for nonoverlapping first and second wavelength ranges, the optical diffuser (10) has a first scattering rate R1 for at least one wavelength in the first wavelength range, and a second scattering rate R2 for at least one wavelength in the second wavelength range, such that R1/R2 is greater than or equal to 2. The first reflective polarizer (40) may transmit at least 40% of light for a first polarization state for each wavelength in the first wavelength range, may reflect at least 70% of light for an orthogonal second polarization state for each wavelength in the first wavelength range, and transmit at least 40% of light for each of the first and second polarization states and for each wavelength in the second wavelength range.

Abstract: A system may include one or both of a light emitter and a light receiver. The system may include an optical filter adjacent one or both of the light emitter or the light receiver. The optical filter includes a wavelength selective scattering layer. The wavelength selective scattering layer may have a near-infrared scattering ratio of less than about 0.9. The filter may have a visible reflective haze ratio of greater than about 0.5. A method may include disposing the wavelength selective scattering layer adjacent one or both of the light emitter and the light receiver. An article may include the optical filter. The wavelength selective scattering layer may have an average near-infrared scattering of less than 60%, an average visible scattering of greater than 10%, and a difference between the % total visible reflectance and the % diffuse visible reflectance of less than 20.

Abstract: A system may include one or both of a light emitter (46) and a light receiver (40), and an optical filter (10). The optical filter (10) includes a wavelength selective scattering layer (14). The wavelength selective scattering layer (14) may have a near-infrared scattering ratio of less than about 0.9. The filter (10) may have a visible reflective haze ratio of greater than about 0.5. A method may include disposing the wavelength selective scattering layer (14) adjacent one or both of the light emitter (46) and the light receiver (40). The optical filter (10) may include a wavelength selective reflective layer (16). The optical filter (10) may include a wavelength selective absorbing layer (34). An article may include the optical filter (10).

Abstract: A technique of determining the presence of a species in a sample may include passing light through an optical filter. In an example, the optical filter may include a spatially variant microreplicated layer optically coupled to a wavelength selective filter. The wavelength selective filter may have a light incidence angle-dependent optical band. The spatially variant microreplicated layer may be configured to transmit light to a first optical region of the wavelength selective filter at a first predetermined incidence angle and to a second optical region of the wavelength selective filter at a second predetermined incidence angle.

Abstract: A light control film is disclosed that includes a plurality of spaced apart first regions. Each first region has a substantially low transmission in one or two of a first wavelength range from about 300 nm to about 400 nm, a second wavelength range from about 400 nm to about 700 nm, and a third wavelength range from about 700 nm to about 1200 nm, and a substantially high transmission in the remaining wavelength ranges. The light control film has a viewing angle of less than about 70 degrees along a predetermined first direction.

Abstract: A light control film is described comprising alternating transmissive regions and absorptive regions disposed between the light input surface and the light output surface. The absorptive regions have an aspect ratio of at least 30. In some embodiments, an absorptive layer or reflective layer is disposed between the alternating transmissive regions and absorptive regions and the light input surface and/or light output surface. In another embodiment, the alternating transmissive regions comprise an absorptive material. The light control film can exhibit low transmission of visible light and high transmission of near infrared light. Also described is a light detection system comprising such light control films and a microstructured film.

Abstract: Methods and systems are disclosed herein for a system configured to determine a position of a brain monitoring user device, and a brain state of a user. Based on the determined position and the determined brain state, the system provides access to a set of media guidance application operations corresponding to the determined brain state and to brain regions corresponding to the determined position of the brain monitoring user device.

Abstract: A system may include one or both of a light emitter and a light receiver. The system may include an optical filter adjacent one or both of the light emitter or the light receiver. The optical filter includes a wavelength selective scattering layer. The wavelength selective scattering layer may have a near-infrared scattering ratio of less than about 0.9. The filter may have a visible reflective haze ratio of greater than about 0.5. A method may include disposing the wavelength selective scattering layer adjacent one or both of the light emitter and the light receiver. An article may include the optical filter. The wavelength selective scattering layer may have an average near-infrared scattering of less than 60%, an average visible scattering of greater than 10%, and a difference between the % total visible reflectance and the % diffuse visible reflectance of less than 20.

Abstract: In an example, an example article may include a spatially variant microreplicated layer optically coupled to a wavelength selective filter. The wavelength selective filter may have a light incidence angle-dependent optical band. The spatially variant microreplicated layer may be configured to transmit light to a first optical region of the wavelength selective filter at a first predetermined incidence angle and to a second optical region of the wavelength selective filter at a second predetermined incidence angle.

Abstract: A light control film is disclosed that includes a plurality of spaced apart first regions. Each first region has a substantially low transmission in one or two of a first wavelength range from about 300 nm to about 400 nm, a second wavelength range from about 400 nm to about 700 nm, and a third wavelength range from about 700 nm to about 1200 nm, and a substantially high transmission in the remaining wavelength ranges. The light control film has a viewing angle of less than about 70 degrees along a predetermined first direction.

Abstract: Wavelength-selective films are visibly apparent under the selective wavelength. Wavelength-selective films typically reflect off axis the selected wavelength and therefore can provide high-contrast against a background when applied in a pattern on a substrate. However, it is difficult to apply unique patterned embedded images from film. Disclosed is a cost-effective method and construction of a patterned wavelength-selective image to a substrate. In the disclosed wavelength-selective image, wavelength-selective film particles are applied to an adhesive pattern to create the wavelength-selective image.

Abstract: In some examples, a method may include receiving retroreflected light that indicates at least one retroreflective property of a retroreflective article, wherein retroreflected light is captured at a first distance. The method may include determining a first set of information based at least in part on the at least one retroreflective property of the retroreflective article. The method may include receiving, from the light capture device, an image that includes at least one object, wherein the image is captured at a second distance. The method may include determining, based at least in part on the spatially resolvable property, a second set of information that corresponds to the object in the image. The method may include performing, by a computing device, at least one operation based at least in part on the second set of information.

Abstract: An optical element including an array of microlenses, a pinhole mask, and a wavelength selective filter is described. The pinhole mask includes an array of pinholes with each pinhole in the array of pinholes aligned with a microlens in the first array of microlenses. The wavelength selective filter is adapted to transmit a first light ray having a first wavelength and transmitted from a first microlens in the array of microlenses through a first pinhole in the array of pinholes aligned with the first microlens, and to attenuate a second light ray having the first wavelength and transmitted from the first microlens through a second pinhole in the array of pinholes aligned with a second microlens in the first array of microlenses adjacent to the first microlens.

Abstract: An article includes an optical filter that comprises a wavelength selective reflective layer and at least one wavelength selective absorbing layer. The optical filter has visible transmittance between 400 nm-700 nm of less than about 30% and near infrared transmittance at 830 nm-900 nm greater than about 30%.

Abstract: In some examples, a retroreflective article may include a retroreflective substrate, and an optical pattern embodied on the retroreflective substrate. The optical pattern may include a first optical sub-pattern and a second optical sub-pattern, wherein the optical pattern represents a set of information that is interpretable based on a combination of the first optical sub-pattern that is visible in a first light spectrum and the second optical sub-pattern that is visible in a second light spectrum. The first and second light spectra may be different.

Abstract: Methods and systems are disclosed herein for a system configured to determine a position of a brain monitoring user device, and a brain state of a user. Based on the determined position and the determined brain state, the system provides access to a set of media guidance application operations corresponding to the determined brain state and to brain regions corresponding to the determined position of the brain monitoring user device.

Abstract: The systems and techniques of this disclosure relate to improving work safety in confined spaces by, for example, using machine vision to analyze location marking labels in the confined space to control an unmanned aerial vehicle (UAV) within the confined space. In one example, a system includes a UAV that includes an imaging device and a processor communicatively coupled to the imaging device. The processor may be configured to receive, from the imaging device, an image of a confined space, detect a location marking label within the image, process the image to decode data embedded on the location marking label, and control navigation of the UAV within the confined space based on the data decoded from the location marking label.

Abstract: An optical system includes an oriented polymeric multilayer optical film having a first reflection band, and a light source configured to produce light in an output band and/or a sensor configured to receive light in an input band. The light source and/or sensor is in optical communication with the oriented polymeric multilayer optical film. In some cases, the first reflection band overlaps the input and/or output band at normal incidence, but not at an oblique incidence angle. In some cases, the first reflection band overlaps the input and/or output band at an oblique incidence angle, but not at normal incidence. The optical system can further include a non-birefringent optical filter having a first blocking band where the first blocking band overlaps the first reflection band for at least one of normal incidence or an oblique incidence angle.

Abstract: An article includes an optical filter that comprises a wavelength selective reflective layer and at least one wavelength selective absorbing layer. The optical filter has visible transmittance between 400 nm-700 nm of less than about 30% and near infrared transmittance at 830 nm-900 nm greater than about 30%.