Abstract: In some examples, an article includes a substrate having a surface; a parent optical element set comprising one or more parent optical elements disposed on the surface of the substrate, a child optical element set comprising one or more child optical elements disposed on the surface of the substrate. Each of the parent optical elements has a first retroreflective property and each of the child optical elements has a second retroreflective property different from the first retroreflective property.

Abstract: A non-contact friction ridge capture device is described. The device comprises a device housing, the device housing including an electronics compartment and an illumination shield, with an opening between the electronics compartment and the illumination shield into which a user can insert the user's hand. The device further comprising a camera disposed in the electronics compartment for capturing an image of at least one friction ridge surface on a user's hand. The device further comprises a light source disposed in the electronics compartment, the light source emitting light in the direction of the illumination shield, wherein the peak wavelength of emitted light is in the range of 440 to 570 nanometers (nm). The user's hand is not required to contact the device when the camera captures the image of at least one friction ridge surface on a user's hand.

Abstract: In general, techniques are described for a personal protective equipment (PPE) management system (PPEMS) that uses images of optical patterns embodied on articles of personal protective equipment (PPEs) to identify safety conditions that correspond to usage of the PPEs. In one example, an article of personal protective equipment (PPE) includes a first optical pattern embodied on a surface of the article of PPE; a second optical pattern embodied on the surface of the article of PPE, wherein a spatial relation between the first optical pattern and the second optical pattern is indicative of an operational status of the article of PPE.

Abstract: In an example, a method includes capturing one or more friction ridge images of a finger at an instance in time, the one or more friction ridge images including a plurality of perspectives of the finger. The method also includes determining, from the one or more friction ridge images, a rolled fingerprint representation of the finger, the rolled fingerprint representation comprising data from the plurality of perspectives, and outputting the rolled fingerprint representation.

Abstract: Systems and methods for authenticating material samples are provided. Characteristic features are measured for a batch of material samples that comprise substantially the same composition and are produced by substantially the same process. The measured characteristic features have respective variability that is analyzed to extract statistical parameters. In some cases, reference ranges are determined based on the extracted statistical parameters for the batch of material samples. The corresponding statistical parameters of a test material sample are compared to the reference ranges to verify whether the test material sample is authentic.

Abstract: Optical articles including a spatially defined arrangement of a plurality of data rich retroreflective elements, wherein the plurality of retroreflective elements comprise retroreflective elements having at least two different retroreflective properties and at least two different optical contrasts with respect to a background substrate when observed within an ultraviolet spectrum, a visible spectrum, a near-infrared spectrum, or a combination thereof.

Abstract: The present disclosure includes in one instance an optical article comprising a data rich plurality of retroreflective meats that are configured in a spatially defined arrangement, where the plurality of retroreflective elements comprise retroreflective elements having at least two different retroreflective properties, and where data rich means information that is readily machine interpretable. The present disclosure also includes a system comprising the previously mentioned optical article, an optical system, and an inference engine for interpreting and classifying the plurality of retroreflective elements wherein the optical system feeds data to the inference engine.

Abstract: In one example, a system includes one or more personal protective equipment (PPE) devices each configured to be worn by a worker, the PPE devices each including one or more sensors that generate activity data indicative of activities of workers operating within one or more work environments. The system also includes a computing device, the computing device configured to: identify, based at least on the activity data, a plurality of clusters of one or more entities, wherein each entity of the entities is associated with one or more of the workers; and output an indication of a difference between performance by a target entity with respect to safety events and performance by the cluster that includes the target entity with respect to safety events.

Abstract: In some examples, an article includes a substrate having a surface; a parent optical element set comprising one or more parent optical elements disposed on the surface of the substrate, a child optical element set comprising one or more child optical elements disposed on the surface of the substrate. Each of the parent optical elements has a first retroreflective property and each of the child optical elements has a second retroreflective property different from the first retroreflective property.

Abstract: Systems and methods for generating random bits by using physical variations present in material samples are provided. Initial random bit streams are derived from measured material properties for the material samples. In some cases, secondary random bit streams are generated by applying a randomness extraction algorithm to the derived initial random bit streams.

Abstract: In some examples, a method includes determining, by a computing device, a plurality of regions of interest of an image for independently processing relative to a plane of interest; determining, by the computing device and for respective regions of interest of the plurality of regions of interest, a distance from objects within the respective regions of interest to the plane of interest; and processing, by the computing device and independently for the respective regions of interest, the respective regions of interest of the image based on the determined distance from the objects to the plane of interest.

Abstract: Systems and methods for generating random bits by using physical variations present in material samples are provided. Initial random bit streams are derived from measured material properties for the material samples. In some cases, secondary random bit streams are generated by applying a randomness extraction algorithm to the derived initial random bit streams.

Abstract: A non-contact friction ridge capture device is described. The device comprises a device housing, the device housing including an electronics compartment and an illumination shield, with an opening between the electronics compartment and the illumination shield into which a user can insert the user's hand. The device further comprising a camera disposed in the electronics compartment for capturing an image of at least one friction ridge surface on a user's hand. The device further comprises a light source disposed in the electronics compartment, the light source emitting light in the direction of the illumination shield, wherein the peak wavelength of emitted light is in the range of 440 to 570 nanometers (nm). The user's hand is not required to contact the device when the camera captures the image of at least one friction ridge surface on a user's hand.

Abstract: A projection system capable of projection alignment includes a projector, a shaped projection screen, an image sensor, and a processing unit. The projector is configured to project a series of alignment content to the shaped projection screen. The image sensor is configured to capture a series of projected alignment content. The processing unit is electronically coupled to the image sensor and configured to receive the series of captured alignment content and determine at least part of general boundary of the shaped projection screen based on the series of captured alignment content.

Abstract: A non-parametric computer implemented system and method for creating a two dimensional interpretation of a three dimensional biometric representation. The method comprises: obtaining with a camera a three dimensional (3D) representation of a biological feature; determining a region of interest in the 3D representation; selecting an invariant property for the 3D region of interest; identifying a plurality of minutiae in the 3D representation; mapping a nodal mesh to the plurality of minutiae; projecting the nodal mesh of the 3D representation onto a 2D plane; and mapping the plurality of minutiae onto the 2D representation of the nodal mesh. The 2D representation of the plurality of minutiae has a property corresponding to the invariant property in the 3D representation; and the value of the corresponding property in the 2D projection matches the invariant property in the 3D representation.

Abstract: Three-dimensional test objects provide for assessment of a 3D scanner over a range of scales, frequencies, and/or depths. The test objects may include a substrate having a substantially planar top surface and a plurality of surface features. In some examples, the surface features include a plurality of wedges projecting above the plane of the top surface and extending radially outward from an origin to form a three dimensional star pattern. The shape of the surface features may be periodic or non-periodic. In other examples, the depth of the surface features is decoupled from their lateral frequency.

Abstract: Systems and methods for authenticating material samples are provided. Characteristic features are measured for a batch of material samples that comprise substantially the same composition and are produced by substantially the same process. The measured characteristic features have respective variability that is analyzed to extract statistical parameters. In some cases, reference ranges are determined based on the extracted statistical parameters for the batch of material samples. The corresponding statistical parameters of a test material sample are compared to the reference ranges to verify whether the test material sample is authentic.

Abstract: An optical film includes a polymeric bandstop filter reflecting a band of blue light in a range from 440 nm to 480 nm a polymeric bandstop filter reflecting a band of blue light in a range from 440 nm to 480 nm and transmitting greater than 50% of blue light at a wavelength of 10 nm longer than a long wavelength band edge and at a wavelength of 10 nm shorter than a short wavelength band edge.

Abstract: A display system includes a switchable display screen comprising a first transparent substrate, a first transparent conductive layer disposed upon the first transparent substrate, a second transparent substrate, and a second transparent conductive layer disposed upon the second transparent substrate. The display screen further includes a polymer-stabilized cholesteric texture layer and spacer elements disposed between and in contact with the first transparent conductive layer and the second conductive layer. The display screen comprises a plurality of addressable regions, each region capable of being switched from a transparent state to a diffuse state.