Abstract: A light directing film includes a structured major surface with a plurality of microstructures extending along a first direction. Each microstructure has a first region and a second region different from the first region, a substantially constant height in the first region and a non-constant maximum height in the second region greater than the substantially constant height in the first region, and a same lateral cross sectional shape in the first region and the second region.

Abstract: A light directing film includes a structured major surface with a plurality of microstructures extending along a first direction. Each microstructure has a first region and a second region different from the first region, a substantially constant height in the first region and a non-constant maximum height in the second region greater than the substantially constant height in the first region, and a same lateral cross sectional shape in the first region and the second region.

Abstract: A light directing film includes a structured major surface with a plurality of microstructures extending along a first direction. Each microstructure has a first region and a second region different from the first region, a substantially constant height in the first region and a non-constant maximum height in the second region greater than the substantially constant height in the first region, and a same lateral cross sectional shape in the first region and the second region.

Abstract: An article comprises an optically transmissive substrate comprising a plurality of functional elements and an integral fiducial mark. The substrate has a critical angle for total internal reflection, and a length and a width defining a reference plane. The substrate comprises an integral fiducial mark disposed on the major surface. The integral fiducial mark comprises at least one substantially ellipse-like feature formed by first and second frustoconical surfaces that together with a reference line that is normal to the reference plane define respective first and second half angles. The first and second half angles are less than or equal to 90 degrees minus the critical angle for total internal reflection expressed in degrees. A method comprises: providing an optically transmissive substrate according to the present disclosure; precisely detecting a position of the fiducial mark with aid of a machine vision system; and optionally precisely aligning the substrate.

Abstract: A light directing film includes a structured major surface with a plurality of microstructures extending along a first direction. Each microstructure has a first region and a second region different from the first region, a substantially constant height in the first region and a non-constant maximum height in the second region greater than the substantially constant height in the first region, and a same lateral cross sectional shape in the first region and the second region.

Abstract: An approach for making a master tool used to fabricate optical films involves cutting a series of base structures. Modifying features are superimposed with the base structures, producing abruptly discontinuous variations in the shape of the base structures. Diffraction elements may be formed in one or both of the base structures and the modifying features. The modifying features can be formed by moving the cutting tool in the x-direction, in the z-direction, or along a trajectory having both an x component and a z component.

Abstract: A cutting tool assembly having a tool post capable of lateral movement along a work piece to be cut and an actuator with at least one machined tool tip and possibly other tool tips. The actuator provides for control of the movement of the tool tip in an x-direction into and out of the work piece in order to make continuous or discontinuous diffractive features in it. The machined work piece can be used to make articles having diffractive features such as optical films having lenslets.

Abstract: Test method for determining (e.g. prism) microstructure deformation of a microstructured (e.g. brightness enhancing) film are described.

Abstract: A cutting tool assembly having a tool post capable of lateral movement along a work piece to be cut and a shank on the tool post holding at least one machined tool tip and possibly other tool tips. The tool tip has diffractive features in contact with the work piece in order to machine macro-scale features having nano-scale features. The machined work piece can be used to make articles having diffractive features such as optical films having lenslets.

Abstract: A cutting tool assembly having a tool post capable of lateral movement along a work piece to be cut and an actuator with at least one machined tool tip and possibly other tool tips. The actuator provides for control of the movement of the tool tip in an x-direction into and out of the work piece in order to make continuous or discontinuous diffractive features in it. The machined work piece can be used to make articles having diffractive features such as optical films having lenslets.

Abstract: A cutting tool assembly having a tool post capable of lateral movement along a work piece to be cut and an actuator with at least one machined tool tip and possibly other tool tips. The actuator provides for control of the movement of the tool tip in an x-direction into and out of the work piece in order to make continuous or discontinuous diffractive features in it. The machined work piece can be used to make articles having diffractive features such as optical films having lenslets.

Abstract: Test method for determining (e.g. prism) microstructure deformation of a microstructured (e.g. brightness enhancing) film are described.

Abstract: A cutting tool assembly having a tool post capable of lateral movement along a work piece to be cut and a shank on the tool post holding at least one machined tool tip and possibly other tool tips. The tool tip has diffractive features in contact with the work piece in order to machine macro-scale features having nano-scale features. The machined work piece can be used to make articles having diffractive features such as optical films having lenslets.

Abstract: A cutting tool assembly having a tool post capable of lateral movement along a work piece to be cut and an actuator with at least one machined tool tip and possibly other tool tips. The actuator provides for control of the movement of the tool tip in an x-direction into and out of the work piece in order to make continuous or discontinuous diffractive features in it. The machined work piece can be used to make articles having diffractive features such as optical films having lenslets.

Abstract: A web of material has a plurality of stems extending from at least one side of the web. The web includes a first layer of material having a first side and a second side and a second layer of material. The second layer of material has a first side which faces the first side of the first layer and a second side from which the plurality of stems extend. The first and second layers of material are joined together while they are both molten, before either layer has cooled. The first and second layers of material can be formed of thermoplastic material or melt processable polymeric material. A method of making a web of material includes selecting a first material for a first layer of material and selecting a second material for a second layer of material. The first and second layers of material are melt formed. Then, the first and second layers of material are joined while the layers are in the molten state to form a multiple layer sheet.