Abstract: Acoustic imaging systems can include an acoustic sensing array, an electromagnetic imaging tool, a display, and an audio device. A processor can receive data from the acoustic sensor array and the electromagnetic imaging tool to generate a display image combining acoustic image data and electromagnetic image data. Systems can include an audio device that receives an audio output from the processor and outputs audio feedback signals to a user. The audio feedback signals can represent acoustic signals from an acoustic scene. Systems can provide a display image to a user including acoustic image data, and a user can select an acoustic signal for which to provide a corresponding audio output to an audio device. Audio outputs and display images can change dynamically in response to a change in pointing of the acoustic sensing array, such as by changing a stereo audio output.

Abstract: An apparatus for optically measuring a distance to a scattering target object or a reflecting target object includes a laser beam source which is embodied as a first electro-optical component, a detector which is embodied as a second electro-optical component and which receives a reception beam that has been scattered at the scattering target object or a reception beam that has been reflected at the reflecting target object, and a laser beam shaping device with a first laser beam shaping optical unit and a second laser beam shaping optical unit where the second laser beam shaping optical unit is disposed downstream of the first laser beam shaping optical unit in a beam path of a laser beam. The second laser beam shaping optical unit is embodied as a first array of reflecting transmission elements where an orientation of the reflecting transmission elements is adjustable by a first control unit.

Abstract: A distance measurement apparatus including: a control unit that controls a projection state of light based on a detection result of a target object; a light projection unit that projects light controlled by the control unit onto the target object; and a processing unit that determines a distance to the target object based on a detection result of reflected light. With this, it is possible to accurately project the light onto the target object and determine the distance to the target object by: controlling the projection state of the light based on the detection result of the target object to project the light onto the target object; and determining the distance to the target object based on the detection result of the reflected light.

Abstract: The present disclosure relates to a localization method and apparatus, and a computer apparatus and a computer-readable storage medium. The localization method includes performing radar mapping and visual mapping by respectively using a radar and a vision sensor, wherein a step of the vision mapping includes determining a pose of a key frame; and combining radar localization with vision localization based on the pose of the key frame, to use vision localization results for navigation on a map obtained by the radar mapping.

Abstract: Systems and methods for camera height detection include a time of flight (TOF) sensor included on a camera within a camera array that emits a signal in an array of points. After receiving a reflected signal at the TOF sensor, where the reflected signal is a bounce back of the emitted signal from at least a subset of the array of points, a distance to each respective point in the array is determined based on a time it takes to receive the reflected signal from each respective point in the array. A depth map is generated from each respective point, where the depth map provides distance measurements to objects within an environment of the camera. A vertical position of the camera is determined based on the depth map.

Abstract: A laser scanner or laser profiler for scanning of an object surface by measuring of distances to surface points comprising a light pulse source, a transmission unit, a receiving unit for receiving measurement light reflected from the object surfaces and for determining the respective distance to a surface point based on the received measurement light according to the principle of time-of-flight and a fiber network with a fiber based optical coupler being designed for transforming a respective light pulse into a series of spaced sub-pulses of different energies. The sub-pulses are digitally sampled, at least one of the sub-pulses having an energy yielding an electrical signal amplitude in the non-saturated range of the receiving unit is selected, and a respective distance is determined based on deducing a time-of-flight of the at least one selected sub-pulse.

Abstract: A sensor device (10) for photon-based imaging comprising one or more photon detectors configured to produce a plurality of photon detection signals in response to a plurality of photon detection events, wherein each photon detection event has a corresponding detection time and wherein the detection times of the plurality of photon detection events are distributed in accordance with a distribution over time; and processing circuitry configured to perform a sketching process using timing information of the plurality of photon detection events to obtain a compressed representation of the distribution over time, wherein the sketching process comprises: generating a plurality of feature values based on the timing information of the plurality of photon detection events using one or more feature functions; combining the generated plurality of feature values to obtain the compressed representation of the distribution over time, wherein the feature functions have one or more properties such that combining the pluralit

Abstract: A projector sequentially generates light pulses to form a sparse grid array. The light pulses reflect off objects in an environment and are reflected towards a sensor array. The sensor array sequentially senses the reflected light pulses across pixels of the sensor array. A depth sensing system calculates depth information of objects in the environment based on the sequential nature of the pulse generation and the pulse sensing. The depth sensing system calculates depth information based on both the positional and temporal information of generated light pulses, and the positional and temporal information of sensed light pulses. The depth sensing system may generate a representation of the environment based on the depth information.

Abstract: Systems and methods for determining a presence of water along a surface from Light Detection and Ranging (LiDAR) point clouds is provided. The method comprises generating, using a LiDAR system coupled to a vehicle, at least one point cloud, wherein the LiDAR system comprises a processor, and, using the processor, identifying and isolating a ground plane within the at least one point cloud, identifying one or more objects within the at least one point cloud, determining whether a reflection of the one or more objects is present in the at least one point cloud below the ground plane, and, when the reflection is present, determining that water is present along a surface.

Abstract: An example system includes an infrared emitter to output infrared light towards a target, where the infrared light reflects from the target to produce reflected infrared light, and a detector to receive the reflected infrared light and to provide a signal based on the reflected infrared light. The system also includes a lighting system that includes a light emitter to output visible light, a mirror configured (i) to allow the visible light to pass through the mirror and to reflect the reflected infrared light onto the detector, or (ii) to allow the reflected infrared light to pass through the mirror and onto the detector and to reflect the visible light, and one or more optical elements configured to affect the visible light and the reflected infrared light.

Abstract: An integrated lamp device for a vehicle includes a first light source module for lidar sensing and a second light source module for beam patterning installed in a single housing, thereby reducing an overall size. Further, an aiming adjustment is performed by a reflection unit separated from the light source modules, thereby stabilizing a structure and ensuring durability performance.

Abstract: A Lidar system may include a first laser, a second laser, and a detection unit for detecting laser radiation of the first and second lasers. The first laser in a first wavelength range and the second laser in a second wavelength range may be configured for periodically tuning a respective emission wavelength. A first tuning time T1 of the first laser may differ from a second tuning time T2 of the second laser.

Abstract: A light detection and ranging (LIDAR) system, includes a memory, and a processor, operatively coupled to the memory, to identify an obstruction of the LIDAR system based on a comparison of a frequency of an energy peak generated from a return signal to a threshold frequency and mitigate the obstruction.

Abstract: A GNSS signal multipath detection device (16) for a GNSS receiver (12) on-board a carrier further comprising one or a plurality of antennas (14) and comprising: a movement generation module (22) configured for generating a movement of an apparent phase center according to a control law; a control module (23) configured for determining the control law; a prediction module (24) configured for determining a prediction of an observable value provided by the GNSS receiver (12), from the control law and directions of arrival of the GNSS signals; an anomaly detection module (25) configured for detecting multipaths by comparing an observable value coming from the GNSS receiver (12) with the corresponding prediction thereof.

Abstract: A GNSS emergency monitoring error suppression method for an alpine canyon complex environment is provided. Through three steps of GNSS optimization design of the alpine canyon complex environment, derived error suppression of emergency monitoring criteria in the alpine canyon complex environment, and error suppression measurement and result correction, GNSS measurement errors in the alpine canyons can be effectively suppressed. Through improving measurement accuracy, GNSS technology can be widely applied to the alpine canyons, outstanding advantages of high efficiency and high accuracy in a coordinate transmission process of the GNSS technology are brought into full play, and a cost is effectively reduced. Meanwhile, by processing the errors of the emergency monitoring criteria, it is possible to protect workers from on-site operation risks.

Abstract: According to one configuration, an example communication system includes multiple communication devices such as a primary wireless access point and a secondary wireless access point (such as a so-called wireless network extender). The primary wireless access point can be configured to control operation of the secondary wireless access point. A communication management resource (such as location management function) associated with the communication system receives first location information indicating a location of the secondary wireless access point. The communication management resource determines a relative position of the primary wireless access point with respect to the secondary wireless access point. Based on the first location information and the determined relative position, the communication management resource produces (derives) second location information indicating a location of the primary wireless access point.

Abstract: An access node, user equipment, an apparatus, a method, and a computer program for determining a delay-Doppler resolution (DDR) for a radio link between two transceivers of a mobile communication system. The method for determining a delay-Doppler resolution (DDR) for a radio link between two transceivers of a mobile communication system includes obtaining information on a radio channel between the two transceivers and deriving the DDR for the radio link based on the information on the radio channel between the two transceivers.

Abstract: A method for determining a protection level of a position estimate using a single epoch of GNSS measurements, the method includes: specifying a prior probability density P(x) of a state x; specifying a system model h(x) that relates the state x to observables z of the measurements; quantifying quality metrics q associated with the measurements; specifying a non-Gaussian residual error probability density model f(r|?, q) and fitting model parameters ? using a set of experimental data; and defining a posterior probability density P(x|z, q, ?); estimating the state x; and computing the protection level by integrating the posterior probability density P(x|z, q, ?) over the state x.

Abstract: A positioning apparatus (100) detects pseudo ranges and carrier phase integrated values from ranging signals (L1C/A) for which augmentation information ([LC/A]) is provided, detects pseudo ranges and carrier phase integrated values from ranging signals (B1C) for which augmentation information is not provided, acquires correction data ([LC/A]) for the ranging signals generated from the augmentation information, corrects the pseudo ranges and the carrier phase integrated values of the ranging signals (L1C/A) with the correction data ([LC/A]), generates a first observation equation using the corrected pseudo ranges and carrier phase integrated values of the ranging signals (L1C/A), generates a second observation equation using a time difference value between the pseudo ranges and a time difference value between the carrier phase integrated values of the ranging signals (B1C), and performs positioning by executing a filter operation using the first observation equation and the second observation equation.

Abstract: A post-processed GNSS solution from raw GNSS data acquired from a vehicle and optionally other sources is dynamically calculated at the epoch level without using a Kalman filter. Instead, a plurality of GNSS processing methods is applied to each epoch in either the forward or backward direction and the most accurate solution for each epoch of the forward generated solution and backward generated solution is combined. The combined post-processed GNSS solution is determined based on which of the GNSS processing methods were used to generate an epoch of the forward solution and a corresponding epoch of the backward solution.

Abstract: The invention relates to a method for determining the quality of an imaging plate, comprising the steps of carrying out an exposure of the imaging plate, carrying out a scan of the imaging plate in order to determine an image, determining a signal-to-noise ratio of the image or/and carrying out edge recognition on the image and calculating a quality value of the imaging plate on the basis of the signal-to-noise ratio of the image or/and on the basis of the recognized edge structure. Furthermore, the invention relates to an imaging plate scanner for carrying out such a method.

Abstract: A radiation detector includes a sensor panel having a light receiving surface, a first scintillator panel and a second scintillator panel disposed on the light receiving surface in a state of being adjacent to each other along the light receiving surface, and an adhesive layer. The first scintillator panel has a first substrate and a first scintillator layer including a plurality of columnar crystals. The second scintillator panel has a second substrate and a second scintillator layer including a plurality of columnar crystals. The first scintillator layer reaches at least a first portion of the first substrate. The second scintillator layer reaches at least a second portion of the second substrate. The adhesive layer is provided continuous over the first scintillator panel and the second scintillator panel.

Abstract: A radiation image photographing apparatus including: a base material that is made of a charged material, a radiation sensor that is provided on the side of a first surface of the base material and detects radiation, a housing that houses the base material and the radiation sensor, and an antistatic member that is provided between the housing and a second surface on the opposite side of the first surface of the base material.

Abstract: Provided are a device for detecting sub-atomic particles and method of fabrication thereof. The device includes a plurality of scintillators, a detector provided on a first end of the plurality of scintillators and a prismatoid provided on a second end of the plurality of scintillators. The prismatoid redirects light between adjacent scintillators of the plurality of scintillators.

Abstract: A seismic source for generating seismic waves under water includes an operating head having an operating chamber, a cushion chamber, and discharge ports, a firing chamber attached to the operating head, the firing chamber configured to hold compressed air to be discharged through the discharge ports, and a shuttle assembly having a shaft located within the operating head and configured to prevent the compressed air in the firing chamber to enter the discharge ports when in a close state, and to allow the compressed air in the firing chamber to be discharged through the discharge ports when in an open state. The shaft of the shuttle assembly which extends in both the operating chamber and the cushion chamber, has a channel having a varying depth.

Abstract: A method is described for seismic imaging including receiving a full waveform inversion (FWI) image of a subsurface volume of interest including complex geology; transforming the FWI image to the Fourier domain to generate a Fourier domain image; performing a multi-dimensional low-cut filter of the Fourier domain image to generate a low-cut filter image; phase rotating by 90 degrees the low-cut filter image to generate a phase-rotated image; performing an inverse Fourier transform on the phase-rotated image to generate a transformed image; and displaying the transformed image on a graphical display. The method is executed by a computer system.

Abstract: Systems and methods for automated first arrival picking are disclosed. The method includes obtaining a seismic dataset composed of a plurality of seismic gathers and determining a pilot for each gather, where the pilot includes a position on an ordinate axis for each seismic trace representing a first arrival. The method continues iteratively until a stopping criterion is met by creating a preconditioned gather using the pilot, determining a differential pilot using global path tracing subject to a constraint and incrementing the pilot using the differential pilot to create a total picked first arrival. Once the stopping criterion has been met, the method further includes determining a final picked first arrival based on the total picked first arrival, determining a seismic velocity model from the final picked first arrival using a tomographic inversion and creating a seismic image using the seismic velocity model and the seismic dataset.

Abstract: A cloud-based, time-limited, confidentiality-rated data management system for survey ancillary data associated with acquisition of seismic data during at least one seismic survey. The system includes a database module configured to store in a first region the survey ancillary data, a data application configured to interact with the database module and upload or download the survey ancillary data, a time module configured to count a lifetime associated with the survey ancillary data, and an erase module configured to erase the survey ancillary data from the database module at the end of the lifetime counted by the time module. The lifetime of the survey ancillary data is shorter than a duration of the seismic survey.

Abstract: A system to perform marine surveying may include a pair of identical design autonomous marine survey vehicles configured for coordinated operations. The vehicles may navigate and transit from a launch location to a geographically distant designated survey location, continuously survey and transit to a designated recovery location. A pair of vehicles may operate interchangeably at the sea surface, semi-submerged and underwater. Each may generate energy when operating at the surface and store energy in a rechargeable battery to power vehicle operation. The payload may include a sensor system to acquire seabed sensor data. A data storage system may store the sensor data. An on-board payload quality control system may analyze data validity. Positioning when the vehicle is collecting seabed sensor data may be determined with high precision, to provide survey data of high precision.

Abstract: Systems and methods are disclosed. The method includes obtaining a first seismic dataset generated by a passive seismic source at a first epoch for an inter-wellbore region of interest lying between a first wellbore and a second wellbore. The first seismic dataset includes a first plurality of seismic traces recorded by a first optical fiber in the first wellbore and a second plurality of seismic traces recorded by a second optical fiber in the second wellbore. The method further includes determining a first virtual seismic dataset by applying seismic interferometry to the first seismic dataset. The method still further includes determining a first seismic velocity model for the inter-wellbore region of interest by applying seismic inversion to the first virtual seismic dataset.

Abstract: Systems and methods of the present disclosure relate to signal attenuation for acoustic logging tools. An acoustic logging tool includes acoustic transducers. Each acoustic transducer includes a body, a piezoelectric element disposed on a first end of the body to receive or transmit at least one signal, and a wedge-cut disposed on an opposite end of the body. The wedge-cut defines a sloped portion operable to attenuate signals.

Abstract: A hand-held metal detector coil, including a coil housing which houses aggregate transmit windings and aggregate receive windings. The aggregate transmit windings include a major group of transmit windings that includes a first transmit winding, and the aggregate receive windings include a major group of receive windings that includes a first receive winding; the coil further includes a minor group of windings to null the aggregate receive windings with respect to the aggregate transmit windings. In an absence of external influences, a mutual inductance coupling coefficient between the aggregate receive windings and the aggregate transmit windings, kTR, is <0.03.

Abstract: Through analysis on an effective detection space of a gamma detector, a one-dimensional equivalent longitudinal contribution coefficient (varying with a distance between a formation and the detector) of a natural gamma-ray flux received by the gamma detector under the condition that the formation and a wellbore are orthogonal is obtained in the effective detection space, and then a corresponding function expression is given by fitting. An integral of a gamma-ray flux received by the detector under the condition of a deviated well is converted into a one-dimensional equivalent integral problem under the condition of a straight well, so as to achieve the fast forward of natural gamma-ray logging of the formation under the conditions of highly-deviated and horizontal wells. This simplified fast forward algorithm can replace a gamma forward method of spherical spatial-division integrals in parallel sedimentary formations, reduce a space-time complexity of algorithms, and improve a calculation efficiency.

Abstract: The present specification discloses a covet mobile inspection vehicle with a backscatter X-ray scanning system that has an X-ray source and detectors for obtaining a radiographic image of an object outside the vehicle. The systems preferably include at least one sensor for determining a distance front at least one of the detectors to points on the surface of the object being scanned, a processor for processing the obtained radiographic image by using the determined distance of the object to obtain an atomic number of each material contained in the object, and one or more sensors to obtain surveillance data from a predefined area surrounding the vehicle.

Abstract: There are provided systems and methods comprising obtaining an image of at least a part of an item, obtaining data informative of a pixel intensity of the part of the item in the image, obtaining first data informative of a pixel intensity in an image of a part of a first item associated with a prohibited material, wherein the part of the first item meets a similarity criterion with the part of the item, obtaining second data informative of a pixel intensity in an image of a part of a second item which is not associated with a prohibited material, wherein the part of the second item meets the similarity criterion with the part of the item, and using the first data, the second data and the data to determine whether the part of the item is associated with a concealed prohibited material in the image.

Abstract: A method can include receiving realizations of a model of a reservoir that includes at least one well where the realizations represent uncertainty in a multidimensional space; selecting a portion of the realizations in a reduced dimensional space to preserve an amount of the uncertainty; optimizing an objective function based at least in part on the selected portion of the realizations; outputting parameter values for the optimized objective function; and generating at least a portion of a field operations plan based at least in part on at least a portion of the parameter values.

Abstract: A metalens and a metalens array having a bounded angular field of view are disclosed. The metalens includes a substrate and a two-dimensional (2D) grid over the substrate to divide the substrate into a 2D array of meta-units. Each meta-unit in the 2D array includes a nanostructure and a portion of the substrate that supports the nanostructure. Moreover, each meta-unit is configured with an angular-dependent transmission or reflection coefficient that decreases with an increasing incident angle of an illumination. Moreover, the metalens passes an incident light having an incident angle less than a cutoff angle and rejects an incident light having an incident angle greater than the cutoff angle. The metalens can be used a base unit for constructing a metalens array by tiling copies of the metalens into a 2D array of the metalens to achieve a significantly larger field-of-view.

Abstract: A mesoscale nonlinear optical gigascope (mNLOG) system is provided to assist with rapid gigapixel resonant-raster laser-scanning and post-processing-free digital display of a centimeter-scale biological specimen in real-time. The mNLOG system enables a half-a-micron digital resolution with satisfied Nyquist-Shannon criterion while providing an aliasing-free optically-sectioned cumulative point-scanning area ranging from 1 square millimeter (mm) up-to 400 square mm. The mNLOG system is configured to perform a rapid artifact-compensated two-dimensional large-field mosaic-stitching (rac2D-LMS) process, so as to provide post-processing-free gigapixel mosaic-stitching and real-time digital display with a sustained effective data throughput of at least 500 Megabits per second (Mbps).

Abstract: A meta-surface optical element includes a substrate and pillars made of a-Si:H and arranged on a surface of the substrate. The pillars on the surface of the substrate are away from each other at a distance in a range of 300 to 450 nm between the centers thereof, the pillars have heights in a range of 300 to 580 nm, and the pillars have diameters in a range of 100 to 250 nm.

Abstract: A meta optical device for forming structured light by modulating incident light having a preset wavelength includes a plurality of supercells each including a plurality of nanostructures having a shape dimension less than the preset wavelength, and shapes and arrangements of the plurality of nanostructures are designed to form the structured light as a point pattern having a viewing angle greater than 160° in horizontal and vertical directions.

Abstract: Disclosed herein is various shared-aperture camera systems and calibration methods. One particular shared-aperture camera system includes a polarization imaging device including: an aperture; a first metasurface configured to diffract incident light going through the aperture such that a first polarization of incident light diffracts in a first direction and a second polarization of the incident light diffracts in a second direction; an image sensor; and a planar diffractive lens including a second metasurface configured to focus the first polarization of incident light diffracted in the first direction onto a first portion of the image sensor and focus the second polarization of incident light diffracted in the second direction onto a second portion of the image sensor.

Abstract: A display device includes a display panel, a middle frame, an annular retaining edge and a cover module. One side of the middle frame is provided with the annular retaining edge around a through hole, a receiving space communicating with the through hole is enclosed by the annular retaining edge and the middle frame, and the display panel is limited in the receiving space; and the cover module includes a protective cover covering a side, with the annular retaining edge, of the middle frame, a first buffer is placed between the protective cover and the display panel, and the protective cover fixes the display panel in the receiving space in a pressing manner through the first buffer. The protective cover fixes the display panel in a first groove in a pressing manner through the first buffer.

Abstract: A cemented lens includes a first optical element, a second optical element, a third optical element sandwiched between the first optical element and the second optical element and containing resin, a light shielding layer covering a surface of the third optical element that is in contact with neither the first optical element nor the second optical element, and a porous layer covering at least a part of the light shielding layer.

Abstract: Disclosed are a motor for driving a liquid state camera lens. Includes at least one sub-motor, the sub-motor is independently controllable, and includes: a fixed member part; a movable member part movable relative to the fixed member part in an optical axis direction of the liquid state camera lens, where the fixed member part includes a fixed guide member, the movable member part includes a movable guide member, a connecting arm, and a plurality of guide balls, and the plurality of guide balls are arranged between the fixed guide member and the movable guide member; the connecting arm is arranged at an end of the movable guide member facing the liquid state camera lens; the movable guide member drives the rigid connecting arm to squeeze the liquid state camera lens when subjected to a force in the optical axis direction; and a driving circuit part.

Abstract: A window includes a window base with a groove having a recessed shape on an upper surface thereof, and a first blocking ink layer and a second blocking ink layer each disposed in the groove, where the first blocking ink layer and the second blocking ink layer are disposed in a same layer as each other, and the first blocking ink layer surrounds the second blocking ink layer in a plan view.

Abstract: A viewing angle diffusion film and a display panel are provided, including a substrate and a plurality of refractive protrusions. Through arranging two adjacent refractive protrusions in a staggered layout with changes periodically in each column of refractive protrusions, that is, initial positions of each column of refractive protrusions are not on a same straight line, a Moire effect can thereby be reduced, improving a quality of the display panel.

Abstract: A bokeh filter membrane, which is disposed on a surface of a substrate, includes a gradient thickness absorbing membrane and an anti-reflection membrane. The anti-reflection membrane includes a high-and-low refraction membrane and a gradient refraction membrane. A transmittance of the substrate at a center thereof is greater than a transmittance of the substrate at a peripheral region thereof. The high-and-low refraction membrane includes a first high-and-low refraction membrane and a second high-and-low refraction membrane, the gradient thickness absorbing membrane is farther away from the substrate than the first high-and-low refraction membrane, the second high-and-low refraction membrane is farther away from the substrate than the gradient thickness absorbing membrane, and the gradient refraction membrane is farther away from the substrate than the second high-and-low refraction membrane. The gradient refraction membrane includes a plurality of pores.

Abstract: A light control film comprises a light input surface and a light output surface opposite the light input surface. Alternating transmissive regions and absorptive regions are disposed between the light input surface and the light output surface. The absorptive regions have an aspect ratio of at least 30 and the alternating transmissive region and absorptive regions have a relative transmission at a viewing angle of 0 degrees of at least 75%.

Abstract: An apparatus is disclosed which includes an ultraviolet laser and at least one reflective mirror having a substrate which is made from beryllium, an aluminum metal matrix, or silicon carbide. The at least one mirror is adapted to reflect a laser beam generated from the ultraviolet laser, which can then be used on a silicon film used in the production of an electronic display. The laser beam can be used to anneal the silicon film, or in a laser lift-off process for separating the silicon film from a temporary substrate upon which the silicon film was mounted.

Abstract: A retroreflective sign comprising a rigid substrate with a pattern of cell walls formed of a polyurethane adhesive or two-part polyurea adhesive, and a polymeric sheet having a front face and a rear face, the rear face facing the substrate, the rear face comprising microprismatic reflective elements is disclosed. The polymeric sheet is adhered directly to the cell walls formed of the polyurethane adhesive or two-part polyurea adhesive while leaving an air gap between the microprismatic retroreflective elements and the rigid substrate in the cells. A method of making the retroreflective sign includes applying a polyurethane adhesive or two-part polyurea adhesive to a front side of a rigid substrate in a pattern defining cell walls; and prior to full curing of the polyurethane adhesive, laminating the front side of the rigid substrate a rear side of a polymeric sheet via the cell walls, the polymeric sheet comprising microprismatic elements.