Abstract: An optical turning film has a first surface including an array of prisms. The array has a plurality of first prisms, with each of the first prisms having a first prism configuration, and a plurality of second prisms, with each of the second prisms having a second prism configuration different from the first prism configuration. The optical film also has a second surface opposing the first surface, and light rays incident to the first surface are directed by the plurality of first prism and the plurality of second prisms along a direction substantially parallel to a viewing axis.

Abstract: A polarized light source includes a diffuse light source and a reflective polarizing element placed proximate thereto. The reflective polarizing element transmits light of a desired polarization and reflects light of another polarization back into the diffuse source where it is randomized. Some of the initially rejected light is thus converted into the desired polarization and is transmitted through the reflective polarizing element. This process continues, and the repeated reflections and subsequent randomization of light of the undesired polarization increases the amount of light of the desired polarization that is emitted by the polarized light source.

Abstract: A cube corner article and method of manufacturing the article from a series of directly machinable unitary substrates. The method of manufacture comprises the first step of providing an initial unitary directly machinable substrate of material suitable for forming retroreflective surfaces. Then, a first cube corner element array zone is formed having a plurality of geometric structures including cube corner elements. The zone is created by directly machining at least two sets of parallel grooves in the substrate. A replica of the cube corner element array zone is formed as an additional unitary substrate suitable for forming retroreflective surfaces. Portions of the replica substrate material are removed. The removal of these portions forms at least two intersecting cavities bounded by side walls in the replica at a depth at least that of the cube corner elements formed by the groove sets.

Abstract: A cube corner article and method of manufacturing the article from a series of directly machinable unitary substrates. The method of manufacture comprises the first step of providing an initial unitary directly machinable substrate of material suitable for forming retroreflective surfaces. Then, a first cube corner element array zone is formed having a plurality of geometric structures including cube corner elements. The zone is created by directly machining at least two sets of parallel grooves in the substrate. A replica of the cube corner element array zone is formed as an additional unitary substrate suitable for forming retroreflective surfaces. Portions of the replica substrate material are removed. The removal of these portions forms at least two intersecting cavities bounded by side walls in the replica at a depth at least that of the cube corner elements formed by the groove sets.

Abstract: The present invention includes a structured optical film with variable pitch peaks and/or grooves to reduce the visibility of moire interference patterns and optical displays incorporating one or more layers of the film. The pitch variations can be over groups of adjacent peaks and/or valleys or between adjacent pairs of peaks and/or valleys.

Abstract: A cube corner article and method of manufacturing the article from a series of directly machinable unitary substrates. The method of manufacture comprises the first step of providing an initial unitary directly machinable substrate of material suitable for forming retroreflective surfaces. Then, a first cube corner element array zone is formed having a plurality of geometric structures including cube corner elements. The zone is created by directly machining at least two sets of parallel grooves in the substrate. A replica of the cube corner element array zone is formed as an additional unitary substrate suitable for forming retroreflective surfaces. Portions of the replica substrate material are removed. The removal of these portions forms at least two intersecting cavities bounded by side walls in the replica at a depth at least that of the cube corner elements formed by the groove sets.

Abstract: A light directing film including a first surface and a second structured surface. The structured surface includes a repeating pattern of prism zones including at least a first zone having a plurality of prism elements with peaks disposed at a first distance from a reference plane and a second zone having a plurality of prism elements with peaks disposed less than the first distance from a reference plane. The width of the first zone preferably measures less than about 300 microns.

Abstract: A cube corner article and method of manufacturing the article from a series of directly machinable unitary substrates. The method of manufacture comprises the first step of providing an initial unitary directly machinable substrate of material suitable for forming retroreflective surfaces. Then a first cube corner element array zone is formed having a plurality of geometric structures including cube corner elements. The zone is created by directly machining at least two sets of parallel grooves in the substrate. A replica of the cube corner element array zone is formed as an additional unitary substrate suitable for forming retroreflective surfaces. Portions of the replica substrate material are removed. The removal of these portions forms at least two intersecting cavities bounded by side walls in the replica at a depth at least that of the cube corner elements formed by the groove sets.

Abstract: The present invention provides a retroreflective material which is efficient at high angles of incidence and which may be individually tailored so as to distribute light retroreflected by the material into a desired pattern or divergence profile.

Abstract: Cube-corner retroreflective article having improved divergence profiles. The three lateral reflecting faces of the cube-corner retroreflective elements are formed by three intersecting sets of parallel V-shaped grooves, and at least one of the sets includes, in a repeating pattern, at least two groove side angles that differ from one another. Thereby the array of cube-corner retroreflective elements is divided into repeating sub-arrays that each comprise a plurality of cube-corner retroreflective elements in a plurality of distinctive shapes that retroreflect incident light in distinctively shaped light patterns.

Abstract: A method for measuring the size of dimple-type defects in an area of the surface of a flat piece of transparent material, such as an optical disc. A large beam of collimated light is provided and passed through the piece of material in a normal orientation with respect to the surface being inspected. A screen is placed in the path of the beam emerging from the disc and circular shadows generated by refraction are measured to determine the size of the defects which produces them.

Abstract: Apparatus for producing a shadowgraph image of a transparent part to be examined, such as part of a video disc. The apparatus includes a source of coherent light, and an objective lens system for focusing the coherent light to produce a divergent beam, a concave mirror disposed in the path of the divergent beam, a transparent plate for supporting the disc to be examined in the aperture of the concave mirror, and a projection screen to receive light reflected from the concave mirror. The apparatus may also include plane mirrors to permit the projection screen to be positioned in a convenient location with respect to the disc being examined.