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.

A retroreflector structure with a plurality of cornercube prisms in a sheet and a projected aperture of at least one of the cornercube prisms has a concave polygon shape with at least one interior angle greater than 180°.

A retroreflector structure with a plurality of cornercube prisms in a sheet and a projected aperture of at least one of the cornercube prisms has a concave polygon shape with at least one interior angle greater than 180°.

A reflector arrangement for determining the position or marking of target points, having at least one retroreflector, and a beam detection unit, by means of which the orientation measurement radiation passing through the retroreflector is acquirable. The beam detection unit comprises a first sensor for generating a signal in dependence on an acquisition of orientation measurement radiation and a first beam guiding unit. The first sensor and the first beam guiding unit are arranged such that a detection field of view for acquiring the orientation measurement radiation is defined, an alignment of the detection field of view around the yaw axis is variable and orientation measurement radiation passing through the retroreflector is acquirable in dependence on the alignment of the detection field of view with the first sensor.

A reflector arrangement for determining the position or marking of target points, having at least one retroreflector, and a beam detection unit, by means of which the orientation measurement radiation passing through the retroreflector is acquirable. The beam detection unit comprises a first sensor for generating a signal in dependence on an acquisition of orientation measurement radiation and a first beam guiding unit. The first sensor and the first beam guiding unit are arranged such that a detection field of view for acquiring the orientation measurement radiation is defined, an alignment of the detection field of view around the yaw axis is variable and orientation measurement radiation passing through the retroreflector is acquirable in dependence on the alignment of the detection field of view with the first sensor.

Display apparatus includes LEDs, bottom chassis to accommodate the LEDs; and reflective member disposed on the bottom chassis. The reflective member includes a reflective bottom portion, and a reflective inclined portion obliquely formed to face a rear surface of the display panel which includes first regions that respectively correspond to LEDs located adjacent to the reflective inclined portion, and second regions each provided between two neighboring first regions and has a reflective characteristic different from a reflective characteristic of a neighboring first region. Second regions and neighboring first regions are on the reflective inclined portion having a uniform incline angle with respect to a side edge of the reflective bottom portion, the first regions include a group of light adjusting members, and the group of light adjusting members of each of the first regions is disposed to correspond to one of the LEDs disposed adjacent to the reflective inclined portion.

The present disclosure relates to end milling methods for making microstructures, a tool comprising such microstructures, the microstructures, and replications thereof, where the microstructures are part of a structured surface configured as a security article. Some of the microstructures are configured differently from others to define an optically detectable indicia in the structured surface. Microstructures in a first group may for example differ from microstructures in a second group in terms of one or more of size, orientation, cube corner type, and dihedral angle value(s), to define the indicia or a portion thereof. The microstructures may comprise full or truncated cube corner elements, and the article may be a retroreflective sheeting.

The present disclosure relates to end milling methods for making microstructures, a tool comprising such microstructures, the microstructures, and replications thereof, where the microstructures are part of a structured surface configured as a security article. Some of the microstructures are configured differently from others to define an optically detectable indicia in the structured surface. Microstructures in a first group may for example differ from microstructures in a second group in terms of one or more of size, orientation, cube corner type, and dihedral angle value(s), to define the indicia or a portion thereof. The microstructures may comprise full or truncated cube corner elements, and the article may be a retroreflective sheeting.

Relay systems and methods are operable to redirect light corresponding to a light field or holographic object such that imagery generated by a light field or other display is perceived by a viewer without having to address the display itself.

The disclosed retroreflective sheet contains a retroreflective layer and a polyurethane surface protecting layer, wherein the surface protecting layer contains at least a reaction product of a polyol with either a polyester backbone or a polycarbonate backbone and a trifunctional or higher aliphatic isocyanate, and the glass transition temperature Tg of the surface protecting layer is 50° C. or higher, and the tan δ of the loss tangent at 120° C. is 0.1 or less.