Light collimating and diffusing film and system for making the film

A method for forming a textured surface on a cylindrical roller, the cylindrical roller being disposed about a first axis and having an external surface and first and second ends, the cylindrical roller further having a first line disposed proximate the external surface extending substantially across the cylindrical roller substantially perpendicular to the first end, the cylindrical roller further having a second line extending around a periphery of the cylindrical portion substantially a predetermined distance from the first end, comprising:

• rotating the cylindrical roller at a predetermined rotational speed about the first axis;
• and
• emitting a pulsating energy beam that contacts the external surface of the cylindrical roller at a predetermined intensity and moving the energy beam from the first end to the second end of the cylindrical roller during the rotation of the cylindrical roller, wherein the energy beam removes portions of the outer surface to obtain the textured surface, the textured surface having a plurality of projecting portions and a plurality of trough portions, wherein each projecting portion extends outwardly from at least one adjacent trough portion, wherein the plurality of projecting portions and the plurality of trough portions define a plurality of slope angles, wherein between 7 to 20 percent of the slope angles on the textured surface proximate the first line or the second line have a value between zero and five degrees.

A method for forming a textured surface on a cylindrical roller, the cylindrical roller being disposed about a first axis and having an external surface and first and second ends, the cylindrical roller further having a first line disposed proximate the external surface, the first line extending substantially across the cylindrical roller substantially perpendicular to the first end, the cylindrical roller further having a second line extending around a periphery of the cylindrical portion substantially a predetermined distance from the first end, comprising:

• rotating the cylindrical roller at a predetermined rotational speed about the first axis;
• applying a dielectric fluid on the cylindrical roller;
• and
• interatively discharging an electric spark from one or more electrodes disposed proximate the cylindrical roller, the electric spark contacting the external surface of the cylindrical roller that heats and melts a predetermined amount of metal on the cylindrical roller to form the textured surface, the electric spark being moved from the first end to the second end of the cylindrical roller during the rotation of the cylindrical roller, the textured surface having a plurality of projecting portions and a plurality of trough portions, wherein each projecting portion extends outwardly from at least one adjacent trough portion, wherein the plurality of projecting portions and the plurality of trough portions define a plurality of slope angles, wherein between 7 to 20 percent of the slope angles on the textured surface proximate the first line or the second line have a value between zero and five degrees.

A method for forming a textured surface on a cylindrical roller, the cylindrical roller being disposed about a first axis and having an external surface and first and second ends, the cylindrical roller further having a first line disposed proximate the external surface, the first line extending substantially across the cylindrical roller substantially perpendicular to the first end, the cylindrical roller further having a second line extending around a periphery of the cylindrical portion substantially a predetermined distance from the first end, comprising:

• rotating the cylindrical roller at a predetermined rotational speed about the first axis;
• and
• iteratively contacting the external surface of the cylindrical roller using a cutting tool at a predetermined frequency, the cutting tool moving from the first end to the second end of the cylindrical roller during the rotation of the cylindrical roller, wherein the cutting tool removes portions of the external surface to obtain the textured surface, the textured surface having a plurality of projecting portions and a plurality of trough portions, wherein each projecting portion extends outwardly from at least one adjacent trough portion, wherein the plurality of projecting portions and the plurality of trough portions define a plurality of slope angles, wherein between 7 to 20 percent of the slope angles on the textured surface proximate the first line or the second line have a value between zero and five degrees.

A method for forming a textured surface on a cylindrical roller, the cylindrical roller being disposed about a first axis and having an external surface and first and second ends, the cylindrical roller further having a first line disposed proximate the external surface, the first line extending substantially across the cylindrical roller substantially perpendicular to the first end, the cylindrical roller further having a second line extending around a periphery of the cylindrical portion substantially a predetermined distance from the first end, comprising:

• coating the cylindrical roller with a chemically resistant layer, wherein the chemically resistant layer is removed at predetermined locations to expose the underlying cylindrical roller surface at the predetermined locations;
• and
• rotating the cylindrical roller at a predetermined rotational speed about the first axis in a container containing an etching solution, wherein the etching solution removes portions of the cylindrical roller at the predetermined locations to obtain the textured surface, the textured surface having a plurality of projecting portions and a plurality of trough portions, wherein each projecting portion extends outwardly from at least one adjacent trough portion, wherein the plurality of projecting portions and the plurality of trough portions define a plurality of slope angles, wherein between 7 to 20 percent of the slope angles on the textured surface approximate the first line or the second line have a value between zero and five degrees.