Methods for producing three dimensional self-supporting, light redirecting roof lighting systems

摘要

A method of producing a light redirecting structure comprising a three dimensional structure formed from a segment of sheet plastics material having at least one parallel or concentric array of cuts 15, 16, 17, 18 is disclosed. The cutting is performed with a laser and may form more than one parallel array of cuts 15, 16, 17, 18. In a first aspect the cutting is performed before the three dimensional structure is formed. The three dimensional structure is formed by locally heating the segment along desired fold lines 19, 20, 21, between the arrays of cuts 15, 16, 17, 18, and folding the segment along the heat softened lines 19, 20, 21. In a second aspect the forming of the three dimensional structure, by folding or moulding, takes place before the cutting and the cuts are made parallel to the base of the structure. In a third aspect the three dimensional shape is a truncated cone and the cuts are concentric about a point which would form the peak of the cone, in this case the whole segment is heated so that it can be formed into the truncated cone.