Abstract: In accordance with at least one aspect of this disclosure, a method of detecting a fault in a plurality of optical detectors includes receiving a first return beam from a first optical detector interrogation beam to generate a first optical signal indicative of an atmospheric condition from a first location on board the aircraft and receiving a second return beam from a second optical detector interrogation beam to generate a second optical signal indicative of the atmospheric condition from a second location on board the aircraft. The method includes, comparing each of the first and second optical signals with a baseline value to determine whether there is a fault in at least one optical detector of the plurality of optical detectors.

Abstract: A sensor assembly includes a housing defining a chamber and having an air inlet. A blower is disposed in the chamber and is in fluid communication with the air inlet. The blower is positioned to direct air in a flow direction. A sensor is disposed in the chamber and has a lens. The sensor is spaced from the blower. An air nozzle is aimed to direct air across the lens. A duct is disposed in the chamber and is coupled to the blower and the air nozzle. The duct extends from the blower in a departure direction oblique to the flow direction.

Abstract: In one example, a LIDAR device includes a light sources that emits light and a transmit lens that directs the emitted light to illuminate a region of an environment with a field-of-view defined by the transmit lens. The LIDAR device also includes a receive lens that focuses at least a portion of incoming light propagating from the illuminated region of the environment along a predefined optical path. The LIDAR device also includes an array of light detectors positioned along the predefined optical path. The LIDAR device also includes an offset light detector positioned outside the predefined optical path. The LIDAR device also includes a controller that determines whether collected sensor data from the array of light detectors includes data associated with another light source different than the light source of the device based on output from the offset light detector.

Abstract: An electromagnetic-wave detection device 10 includes a radiating unit 11, an incidence unit 12, a first detection unit 13, a second detection unit 14, and a controller 15. The radiating unit 11 is configured to radiate electromagnetic waves in multiple different directions within a space. Electromagnetic waves from the space are incident on the incidence unit 12. The electromagnetic waves from the space include reflected waves resulting from electromagnetic waves radiated by the radiating unit 11 being reflected by an object within the space. The first detection unit 13 is configured to detect at least the reflected waves. The second detection unit 14 is configured to detect at least a portion of the electromagnetic waves incident on the incidence unit 12. Based on the detection results of the second detection unit 14, the controller 15 is configured to determine the presence or absence of an interfering factor that may interfere with the detection of reflected waves by the first detection unit 13.

Abstract: Disclosed herein are methods, systems, and devices that relate to light detection and ranging (LIDAR). A controlling means for a LIDAR system includes a means for determining a current operational state of the LIDAR system regarding a predefined threshold state. The controlling means also switches the LIDAR system from a first operational mode to a second operational mode when the determined operational state exceeds the predefined threshold state. The second operational mode corresponds to an operational power of at least one operational means of the LIDAR system being lower than in the first operational mode.

Abstract: A method of calibrating a light-curtain system of an autonomous mobile robot (AMR) is provided. The method includes providing a scanner set at a height above a ground surface and outputting a laser scanning beam downwardly reflect from at least one mirror; providing and/or determining initial mirror angles, mirror positions, and lidar height; calculating a lidar height from scanner data; determining a gradient vector as a byproduct of the lidar height calculating; adjusting mirror angles, mirror positions, and lidar height in a direction opposite of the gradient vector; assessing of the adjusted mirror angles, mirror positions, and lidar height are equal to or less than thresholds; and if so, storing the mirror angles, mirror positions, and lidar height and/or values representing a ground plane.

Abstract: An apparatus, a method, and computer-implemented media.

Abstract: An information processing device includes: a distance measuring section that carries out communication between an own device and a portable terminal by using BLE wireless communication, and, in a case in which strength of a signal relating to the BLE wireless communication is greater than or equal to a predetermined threshold value, starts measuring a distance between the own device and the portable terminal by using UWB wireless communication; a judging section judging whether or not results of distance measuring by the UWB wireless communication satisfy a predetermined operation condition; and a notification section that, in a case in which the operation condition is satisfied, provides the portable terminal with a notice proposing changing of the threshold value.

Abstract: Systems and methods for Wi-Fi sensing using UL-OFDMA are provided. Wi-Fi sensing systems include sensing devices and sensing transmitters configured to communicate through radio-frequency signals. Initially, first channel resources are allocated to first expected transmissions from the sensing transmitters and first sensing trigger message to trigger first series of sensing transmissions from the sensing transmitters is transmitted. Further, a first series of sensing transmissions is received, and the first series of sensing measurements are generated. Thereafter, identification of feature of interest is obtained and a selection of sensing transmitters is determined. Second channel resources are allocated to second expected transmissions from the selection of sensing transmitters. A second sensing trigger message to trigger a second series of sensing transmissions from the selection of the sensing transmitters is provided.

Abstract: An ultra-wideband sensor transmits impulse radio signals over a predetermined time period, detects echo signals of the impulse radio signals by way of at least one sensor of the ultra-wideband sensor and generates a time-variant channel impulse response that describes the echo signals received by the at least one sensor as a function of a time at which the respective impulse radio signal of the predetermined time period was transmitted and a path delay, uses a predetermined selection method to ascertain at least one ascertained path delay, generates a signal characteristic of the time-variant channel impulse response for the at least one ascertained path delay, uses a predetermined comparison method to determine a similarity of the signal characteristic to a reference characteristic, and detects a predetermined movement pattern associated with the reference characteristic if the similarity meets a predetermined similarity criterion.

Abstract: A scanning method and system for measuring microwave vibration and deformation include simultaneously transmitting linear-frequency-modulation continuous waves by using a plurality of transmit antennas and enabling a main lobe of a synthesized beam to be directed towards a specific angle direction; receiving echoes by using a plurality of receive antennas to obtain vibration and deformation displacement values of a single target or multiple targets in an angle direction 1 of a cycle; through the phase shift control on the plurality of transmit antennas, extracting vibration and deformation displacement values of a single target or multiple targets in an angle direction 2 of the cycle based on the foregoing method; according to a measurement requirement, measuring and extracting vibration and deformation displacement values of a single target or multiple targets in another angle direction of the cycle; and obtaining vibration and deformation displacement time sequence values of all scanned points.

Abstract: In accordance with an embodiment, a method includes: for each frame of a plurality of frames over time, obtaining a combined image by combining a plurality of range-Doppler images; for each range and Doppler bin in the combined images, accumulating values each associated to a given frame and indicative of whether a detection has occurred in the corresponding range and Doppler bin in the combined image of the given frame; for each range and Doppler bin in the combined images, determining a moving average based on the values accumulated over time for a corresponding range and Doppler bin; for a current frame, identifying range and Doppler bins in which repeated detection has occurred over past frames based on the moving averages, and generating an updated combined image for the current frame by suppressing the identified range and Doppler bins; and detecting motion in the updated combined image.

Abstract: A flash analog-to-digital converter (ADC) receives an input control signal and performs coarse tuning of a frequency of an output signal, produced between first and second nodes having an inductance coupled therebetween. The flash ADC quantizes an operating frequency range for the output signal produced between the first and second nodes as M·?f, where M is an integer from 0 to N?1, where N is a number of intervals into which a frequency range for the output signal is divided, and where ?f is a resulting frequency step produced by the quantizing. The value of M is generated based upon the input control signal and a word controlling switches of a plurality of switched capacitance circuits associated with the first and second nodes to close ones of those switches associated with the control word to coarsely tune the frequency of the output signal.

Abstract: Embodiments of the present invention provide methods and devices for performing wireless sensing operations that can accommodate different Rx frequency responses with minimum PHY changes to increase the performance and reliability of wireless sensing in wireless local area network (WLAN) networks. Rx frequency response information can be obtained as channel state information (CSI) in a loopback test and can further be normalized with the total gain in the receiver chain leading to CSI estimation. Moreover, different Rx frequency responses can be categorized into limited groups with underlying circuit conditions based on their frequency response variations. The different Rx frequency responses can be indicated in subfields of a CSI report transmitted to the sensing initiator for performing sensing operations with the sensing responder.

Abstract: Existing multistatic configurations of Radar systems requires a direct LoS signal and/or time synchronization among the Radar transmitter and the multistatic distributed Radar receivers. The present disclosure provides a phaseless frequency-modulated continuous-wave multistatic Radar (PFMR) imaging that relaxes requirement of the direct LoS signal and only requires a plurality of parameters of a FMCW signal comprising a chirp signal rate, a carrier frequency and, a period of chirp to be known. Further, it also removes condition of the time synchronization among a plurality of FMCW multistatic distributed Radar receivers. However, because of absence of the time synchronization among a plurality of FMCW multistatic distributed Radar receivers, an unknown random phase offset appears after deramping.

Abstract: An object detection device includes: an acquisition unit configured to acquire distance information indicating a distance from a predetermined portion to an object based on an intensity of a reflected wave generated by an ultrasonic wave being reflected by the object; and a generation unit configured to generate step information indicating a height of the object based on a pair of pieces of distance information detected within a predetermined time interval. The pair of pieces of distance information include first distance information corresponding to a distance from the predetermined portion to an upper end portion of the object and second distance information corresponding to a distance from the predetermined portion to a lower end portion of the object.

Abstract: A method, apparatus, and system detects a speed of a vehicle. A backscatter light generated in response to transmitting a laser beam into an atmosphere during movement of the vehicle is received. A first beat frequency from interfering a first portion of the backscatter light with a reference light derived from the laser beam is measured. A time delay is introduced to a second portion of the backscatter light to form a time delayed backscatter light. A second beat frequency from interfering the time delayed backscatter light with the reference light is measured. The second beat frequency is time delayed from the first beat frequency. A difference between the first beat frequency and the second beat frequency is determined. The speed of the vehicle using the difference between the first beat frequency and the second beat frequency is determined.

Abstract: In the information processing device, the object detection means detects an object based on point cloud data generated by a measurement device provided on a ship. The positional relationship acquisition means to acquires a relative positional relationship between the object and the ship. The display control means displays, on a display device, information related to the positional relationship in a display mode according to the positional relationship.

Abstract: An apparatus, method, and computer program product are provided for the improved and automatic prediction of an elevation of an architectural feature of a structure at a particular geographic location. Some example implementations employ predictive, machine-learning modeling to facilitate the use of LiDAR-derived ground-elevation data, additional location context data, and elevation data from comparator locations to extrapolate and otherwise predict the elevation or other position of a given architectural feature of structure.

Abstract: Systems and methods for determining elevation based on structural modeling and light detection and ranging (LIDAR) data are disclosure. LIDAR bare earth data corresponding to an area within a parcel boundary is obtained as preliminary elevation data. A basis of structure boundary is determined for a structure within the parcel boundary based on an absence of the LIDAR bare earth data within a region in the area. Three-dimensional models are generated based on photographic data, to represent portions of the structure that affect LIDAR signals. A structure boundary for the structure is determined based on the basis of structure boundary in combination with supplemental elevation data generated using the three-dimensional models. Adjacent grade values are determined based on a portion of the preliminary elevation data and supplemental elevation data corresponding to an area between the structure boundary and a buffer boundary.

Abstract: Methods, devices, and computer-readable storage media for LiDAR ranging are provided. In one aspect, a ranging method for a LiDAR includes: acquiring multiple frames of detection data of a three-dimensional environment; predicting, based on at least part of previous k frames of the detection data, a position where an obstacle is located in the three-dimensional environment during (k+1)th detection, k being an integer and k?1; when performing the (k+1)th detection, changing, based on predicted position information of the obstacle, a detection window for at least one point on the obstacle; calculating ranging information of the at least one point only based on echo information within a range of the changed detection window.

Abstract: A measurement device according to an embodiment includes: a receiving unit (100, 102) that receives reflected light of laser light reflected by a target object and polarization-separates the received reflected light into first polarized light and second polarized light, and a recognition unit (122) that performs object recognition on the target object on the basis of the first polarized light and the second polarized light.

Abstract: A sensor assembly includes a housing, a sensor unit attached to the housing, and a gutter fixed relative to the housing. The sensor unit includes a cylindrical shell defining a vertical axis. The cylindrical shell extends above a highest point of the housing. The cylindrical shell is rotatable around the axis relative to the housing. The cylindrical shell includes a lower edge and extending upward along the axis from the lower edge. The gutter is elongated along the lower edge and positioned directly below the lower edge relative to the axis. The gutter defines an airflow outlet from the housing radially inside the gutter relative to the axis. The sensor unit defines an airflow inlet radially inside the lower edge relative to the axis and positioned to receive airflow from the airflow outlet.

Abstract: Various systems and methods for implementing LiDAR-based object tracking described herein. An object tracking system for a vehicle includes an interface to communicate with object detection circuitry and an object similarity calculator circuitry, to obtain segmented data of an environment the object tracking system is operating within, the segmented data obtained using a light imaging detection and ranging (LiDAR) system, and the segmented data including a first plurality of segments detected in a first frame and a second plurality of segments detected in a second frame, the second frame captured after the first frame; determine, for a given segment of the first plurality of segments, a similar segment in the second plurality of segments; assign an VEHICLE object identification of the given segment to the similar segment; and track the similar segment from the first frame to the second frame based on the object identification.

Abstract: A system can include a computing system and optionally a GNSS receiver. The computing system can include a correction generator, one or more correction checker, one or more correction combiner, a positioning engine, and/or any suitable components. The computing system may be designed to be free from interference between components.

Abstract: A clock error prediction method includes: obtaining historical satellite clock error data of a preset time period which includes broadcast ephemeris clock error data and precise ephemeris clock error data; obtaining corrected precise ephemeris clock error data based on the broadcast ephemeris clock error data; obtaining a single-day clock speed of each satellite through fitting based on single-day clock error data in the corrected precise ephemeris clock error data of each satellite; obtaining a clock speed time sequence of each satellite based on the single-day clock speed of each satellite; obtaining a clock speed change rate of each satellite through fitting based on the clock speed time sequence of each satellite; and obtaining a predicted clock error of each satellite in a preset future time period based on an initial clock error value, a clock speed, and the clock speed change rate of each satellite.

Abstract: A method includes a mobile device receiving a plurality of first signals from one or more first transmitters in a network. Each first signal has first data including an associated time that is non-synchronized to the time of another first signal of the plurality of first signals. One or more processors synchronizes the associated time of each first signal to a common time scale. One or more processors determines a position of the mobile device using a common time scale of the plurality of first signals.

Abstract: A method carried out in a user equipment, UE, (1) for generating location information to a location server (130) in a wireless network (100), the method comprising: receiving (404), from the location server, a location request message identifying a request for location information based on adaptive selection of a positioning method; receiving (404,408), from the wireless network, parameter information for the adaptive selection of the positioning method; obtaining (412) location information using the positioning method adaptively selected by the UE based on the parameter information; transmitting (414) the location information to the location server.

Abstract: Reliability of a scintillator structure is improved. The scintillator structure includes a plurality of cells and a reflective layer covering the plurality of cells. Here, each of the plurality of cells includes a resin and a phosphor, and the resin has a decrease rate of a total light transmittance that is less than 8% with respect to light having a wavelength of 542 nm after X-ray irradiation of a dose of 100 kGy.

Abstract: Described is a scintigraphic detection device with a high degree of compactness and simplified electronics, including a scintillation structure, a collimator, an optoelectronic unit associated with the scintillation structure for converting photons into electrical signals and an electronic processing unit connected to the optoelectronic unit for processing the electrical signals generated by the optoelectronic unit, wherein the optoelectronic unit includes a plurality of individual optoelectronic conversion elements of the SiPM or MPPC type each associated with a respective collimation channel and having a surface below the transversal surface of the respective collimation channel, and wherein between each optoelectronic conversion element and the scintillation structure there is an optical guide configured for conveying and for converging the photons generated by a corresponding portion of the scintillation structure towards the optoelectronic conversion element.

Abstract: Fiber reinforced aerogel composites, including a transparent composite material that contains an aerogel and fibers embedded into the aerogel and/or bonded to one or more surfaces of the aerogel, and composites that contain an aerogel tile and an assemblage of fibers embedded into the aerogel tile or bonded to the aerogel tile that are useful as Cherenkov radiators for the detection and identification of subatomic particles. Also, methods of making and using the composites.

Abstract: The present disclosure relates to a system for PET imaging. The system may include a first device and a second device. The first device may include a first scanning channel. The second device may include a second scanning channel connected to the first scanning channel, a heat generating component, and a cooling assembly configured to cool the heat generating component, wherein the cooling assembly may include an inlet chamber and a return chamber, the heat generating component may be closer to a first side of the second device than at least one of the inlet chamber or the return chamber, and the first side of the second device may face the first device.

Abstract: A system includes a tunneling device including a body assembly configured to move through an interior cavity of a tunnel. The system also includes a distributed communication and sensing system and a controller. The distributed communication and sensing system includes a first beacon coupled to the body assembly, and a second beacon positioned outside of the tunnel. The second beacon is communicatively coupled to the first beacon. The controller is configured to compare a first signal transmitted by the first beacon to a second signal transmitted by the second beacon, determine an environmental characteristic of the tunnel based on the first signal and the second signal, and determine an operating parameter for the tunneling device based on the environmental characteristic.

Abstract: There is provided system and methods for providing enhanced high definition of subterranean activities, and structures using migrate data from two independent sources. There are provided systems and methods for imaging and the resultant and images showing hydraulic fracturing and hydraulic fractures.

Abstract: A geological projection system may receive seismic survey data, the seismic survey data including a seismic surface of a geological feature. A geological projection system may receive resistivity sensor data from a downhole resistivity sensor, the resistivity sensor data being for a reference length uphole of a reference depth. A geological projection system may generate a sensed surface over the reference length using the resistivity sensor data. A geological projection system may generate a displacement field of a difference between the sensed surface and the seismic surface for the reference length. A geological projection system may apply an uncertainty model to at least one of the resistivity sensor data, the seismic survey data, or the displacement field, the uncertainty model generating an output including an uncertainty distribution of a projected surface of the geological feature downhole of the reference depth.

Abstract: A subsurface representation of a subsurface region includes cells that define subsurface propert(ies) at different locations within the subsurface region. Initial classification of rock types within portions of the subsurface representation is obtained and used to determine probability distributions of the subsurface propert(ies) for the rock types. The probability distributions of the subsurface propert(ies) for the rock types and a spatial distribution of rock types within the subsurface representation are used in an iterative process to determine classification of rock types within the subsurface representation.

Abstract: Example computer-implemented methods, media, and systems for predicting permeability distribution of deep buried sandstones of a subsurface sandstone reservoir using machine learning. One example method includes receiving multiple wireline well log responses of multiple cored well sections of a subsurface sandstone reservoir. A respective authigenic clay type associated with each of the multiple cored well sections is received. The multiple wireline well log responses are labeled based on the respective authigenic clay type associated with each of the multiple cored well sections. A machine learning (ML) model for predicting a permeability distribution of multiple uncored well sections of the subsurface sandstone reservoir is trained based on the multiple labeled wireline well log responses of the multiple cored well sections. Multiple wireline well log responses of the multiple uncored well sections are received.

Abstract: Methods and systems for improving the efficiency of ALFT are disclosed. The methods include obtaining a seismic dataset of a subterranean region, transforming the seismic dataset from a first domain to a second domain using a transform function, and generating an input spectrum from the transformed seismic dataset. The methods also include iteratively, or recursively, until a condition is met, for each slice, estimating a weight function using the input spectrum, generating a weighted input spectrum using the weight function and the input spectrum, identifying a strongest attribute from the weighted input spectrum, determining an output spectrum based on the identified strongest attribute, and updating the input spectrum by removing the identified strongest attribute from the input spectrum. The methods further include determining an output spectrum volume by combining the output spectrum for each slice, generating an output seismic dataset using an inverse transform function and the output spectrum volume.

Abstract: A pressure wave is generated within a first well extending into a subterranean formation. A pressure response associated with the pressure wave is detected from a second well extending into the formation. Information is then determined, based on the pressure response in the second well, wherein the information is associated with at least one of the formation and a fracture connected to at least one of the first well and the second well.

Abstract: The invention discloses a node multi-electrode resistivity measurement system provided with a transmitter, a PC terminal, acquisition nodes, transmitting electrodes and receiving electrodes. The transmitter, acquisition nodes and PC terminal are connected by Wifi, and the transmitter and acquisition nodes are connected in series by a five-core cable. So the weight of the cable is greatly reduced, and each core can be wrapped by shielding layer, reducing the influence of electromagnetic coupling and ensuring the quality of collected data. The weight of the system is very light so that work efficiency has been improved. Synchronization between transmitter and acquisition nodes is carried out by GPS.

Abstract: The present invention provides a signal acquisition method and device of an azimuthal electromagnetic wave resistivity instrument while drilling. The method comprises: step 1. picking up, by a receiving antenna, a magnetic induction signal after formation attenuation, and converting the received magnetic induction signal into an electrical signal for subsequent circuit processing; step 2. amplifying, by a preamplifier circuit, the fixed gain of a weak signal with nV level amplitude induced on the receiving antenna; step 3. controlling a filtering circuit through a controller, and filtering the amplified signal, wherein the filtering circuit comprises an analog switch and two low pass filters with different frequencies, and for receiving signals with different frequencies, a field programmable gate array (FPGA) controller achieves the selection of the filtering frequency by controlling on/off of the analog switch; step 4. amplifying the filtered signal using a programmable amplifier circuit; and step 5.

Abstract: A method for estimating a pipe property may include disposing an electromagnetic (EM) logging tool in a wellbore. The EM logging tool may comprise a transmitter disposed on the EM logging tool and a receiver disposed on the EM logging tool. The method may further include transmitting an electromagnetic field from the transmitter into a tubular string to energize the tubular string with the electromagnetic field thereby producing an eddy current that emanates from the tubular string. The method may further include measuring the eddy current in the tubular string with the receiver on at least one channel to obtain one or more measurements from the EM logging tool. The method may further include forming an EM log from the one or more measurements, forming a relationship between a set of one or more previously analyzed measurements and at least one pipe property, and estimating the at least one pipe property from the formed relationship and the one or more measurements from the EM logging tool.

Abstract: A water vapor observation apparatus of the present invention includes: an acquiring unit that acquires a water vapor value at each predetermined point measured based on a received signal from a satellite; an extracting unit that extracts a feature value for each predetermined point from a captured image captured from the sky; and a correcting unit that corrects the water vapor value based on the feature value for each predetermined point.

Abstract: An optical device is provided. The optical device includes a substrate that has a top surface and a bottom surface. The optical device also includes a cover layer disposed on the substrate, and the cover layer has a top surface and a bottom surface. The top surface of the cover layer faces the bottom surface of the substrate. The optical device further includes a first meta structure disposed on the bottom surface of the substrate and a second meta structure disposed on the top surface of the cover layer. Moreover, the optical device includes a detector disposed on the bottom surface of the cover layer.

Abstract: An optical metasurface includes a substrate and a plurality of nanostructures extending from a surface of the substrate and constructed of a material having an index of refraction. The plurality of nanostmctures are arranged in a plurality of unit cells comprising a dimension that is less than or equal to twice an effective wavelength of light incident on the optical metasurface, divided by the sinusoid of a deflection angle that the optical metasurface is designed to deflect the light. The plurality of nanostructures are asymmetrically arranged along a deflection direction. A unit cell aspect ratio of the plurality of nanostmctures is greater than or equal to 3, and a product of the unit cell aspect ratio and the index of refraction of the material is greater than or equal to 8.

Abstract: An optical film layer and a manufacturing method thereof, a polarizer, and a display panel are provided. The optical film layer includes a base layer and a group of particle layers arranged in the base layer. The group of particle layers includes multiple particle layers, and refractive indices of the multiple particle layers gradually decrease in a direction from a first side of the optical film layer to a second side of the optical film layer.

Abstract: An optical film includes a transparent substrate, one or more colored layers that contain a colorant and are provided on the transparent substrate, and one or more functional layers that are provided on a side opposite to that on which the transparent substrate is disposed, with the one or more colored layers interposed therebetween. The one or more colored layers contain a first color material in which a maximum absorption wavelength is in a range of 470 nm or more and 530 nm or less and a half-width of an absorption spectrum thereof is 15 nm or more and 45 nm or less, and a second color material in which a maximum absorption wavelength is in a range of 560 nm or more and 620 nm or less and a half-width of an absorption spectrum thereof is 15 nm or more and 55 nm or less.

Abstract: An optical film comprises: a transparent substrate having an ultraviolet blocking rate of 85% or more according to JIS L 1925; one or more functional layers formed on a first surface side of the transparent substrate; and a colored layer that is formed on a second surface side of the transparent substrate that is configured by one or more layers containing a colored material. The colored layer contains a first colorant that has a maximum absorption wavelength in a range of 470 nm or more and 530 nm or less, an absorption spectrum thereof having a half-width of 15 nm or more and 45 nm or less, and a second colorant that has a maximum absorption wavelength in a range of 560 nm or more and 620 nm or less, an absorption spectrum thereof having a half-width of 15 nm or more and 55 nm or less.

Abstract: An optical film includes a structured film and a light control film formed on the structured film. The structured film includes a substrate and a plurality of polymeric microstructures formed on a major surface of the substrate. Each microstructure includes an optical facet and a sidewall meeting the optical facet at a ridge of the microstructure. The light control film includes an optically transparent material disposed on and covering the plurality of polymeric microstructures, and a plurality of optically absorptive louvers formed in the optically transparent material opposite the structured film. The louvers extend along a longitudinal direction and are spaced apart along an orthogonal transverse direction. The louvers have an average depth D into the optically transparent material and have an average width W in the transverse direction. D/W can be greater than 2. The optical film is integrally formed.

Abstract: A removable lens stack includes a base layer and one or more removable lens layers. The base layer may include a substrate and moth eye coatings on first and second sides of the substrate. A first removable lens layer may include a substrate and an acrylic or fluoropolymer coating on a first side of the substrate and may be stacked on top of the base layer such that the second side of the substrate faces the first side of the substrate of the base layer. A second removable lens layer may include a substrate and an acrylic or fluoropolymer coating on a first side of the substrate and may be stacked on top of the first removable lens layer such that the second side of the substrate faces the first side of the substrate of the first removable lens layer. The acrylic or fluoropolymer coating may comprise a hard coat.