An article, including a substrate having a surface with a groove pattern including microprisms thereon. The groove pattern includes a first set of first grooves intersecting with a second set of second grooves, the first grooves are parallel to each other along a same first direction across the groove pattern, and each of the first grooves include a plurality of repeating variable depth zones. Each of the variable depth zones include: a dive section having a first maximum depth, Z.sub.D2, and a rise section having a second maximum depth, Z.sub.R2. The second grooves are parallel to each other along a same second direction across the surface, the second direction being substantially perpendicular to the first direction.

An article. A transparent sheet having a first side with a structured surface including microprisms thereon, the microprisms being part of a microprism array on the structured surface. Each of the microprisms are part of a quaternary set of the microprisms, the first, second, third fourth microprisms having first, second, third lateral faces, a continuous surface transition between the second lateral face of the first microprism and the third lateral face of the second microprism, between the second lateral face of the third microprism and the third lateral face of the fourth microprism. A shared side edge between the second lateral face of the first microprism and the third lateral face of the third microprism and between the third lateral face of the second microprism and the second lateral face of the fourth microprism, visible as a solid tooling line.

Manufacturing an article, including providing a substrate having a surface, forming a first set of first grooves in the surface along a first direction, forming a second set of second grooves in the surface along a second direction substantially perpendicular to the first direction, an intersection of the first and second directions forming an angle of 90?1 degrees. An article including a substrate having a surface with a groove pattern including microprisms thereon. The groove pattern includes a first set of first grooves intersecting with a second set of second grooves. The first grooves are V-shaped having a groove being a sharp or slightly rounded point at the vertex of the V-shaped groove. The second grooves are parallel to each other along a same second direction across the surface, the second direction substantially perpendicular to the first direction.

A retroreflective screen including a first film having a surface including a plurality of microrecesses, each microrecess having a bottom substantially parallel to the mean plane of the screen and first and second lateral walls substantially orthogonal to each other and substantially orthogonal to the bottom, the first and second lateral walls and the bottom of the microrecess joining at a same point and forming a trihedron.

A retroreflector includes an arrangement of triples, each having three side surfaces, which are disposed in the manner of a cube corner and stand approximately perpendicular on one another. The retroreflector can be produced from a carrier material by injection molding. An optical silicone resin is used as the carrier material. The retroreflector is based on triple mirrors that are both easily unmolded from a die and easily applied to curved surfaces even after unmolding or are usable for reflection of ultraviolet light.

A retroreflective screen including a first film having a surface including a plurality of microrecesses, each microrecess having a bottom substantially parallel to the mean plane of the screen and first and second lateral walls substantially orthogonal to each other and substantially orthogonal to the bottom, the first and second lateral walls and the bottom of the microrecess joining at a same point and forming a trihedron.

Various geometries are described for forming retroreflective structures in polymeric sheets or films. The geometries enable venting of volatile gases that can otherwise become trapped between the embossing surface and the polymeric sheet or film. The geometries are incorporated in tooling belts or other pattern forming surfaces.

A retroreflective screen including a first film having a surface including a plurality of microrecesses, each microrecess having a bottom substantially parallel to the mean plane of the screen and first and second lateral walls substantially orthogonal to each other and substantially orthogonal to the bottom, the first and second lateral walls and the bottom of the microrecess joining at a same point and forming a trihedron.

A method of manufacturing a primary mold for the forming of a retroreflective screen, the method including the steps of: a) forming, on the front surface of such a substrate, a layer of a material such that the first substrate is selectively etchable over said layer; and b) forming microrecesses from the rear surface of the first substrate by selective etching of the first substrate over said layer, each microrecess emerging on the rear surface of said layer and having a back parallel to the front surface of the first substrate and first and second lateral walls orthogonal to each other and orthogonal to the back the first and second lateral walls and the back of the microrecess joining at a same point and forming a trihedron.

A retroreflective screen including a first film having a surface including a plurality of microrecesses, each microrecess having a bottom substantially parallel to the mean plane of the screen and first and second lateral walls substantially orthogonal to each other and substantially orthogonal to the bottom, the first and second lateral walls and the bottom of the microrecess joining at a same point and forming a trihedron.