Light redirecting fabric and method of making the same

摘要

A flexible sheet-form optical system, referenced to as a light redirecting fabric, which has a fabric-like behavior and light redirecting properties. The light redirecting fabric comprises a soft and flexible sheet of optically transmissive material, such as plasticized polyvinyl chloride. A surface of the flexible sheet includes a plurality of parallel slits having spaced-apart walls configured to reflect light by means of a total internal reflection. At least a portion of daylight incident onto the sheet is internally redirected at angles other than the angle of incidence which is exploited to enhance daylight harvesting and illumination of a building interior. Disclosed also are a method and apparatus for making the light redirecting fabric. The method includes steps of mechanical slitting of the flexible sheet with a blade, elastic stretch-elongation of the sheet along a direction perpendicular to the slits, and making at least a portion of the sheet elongation irreversible.

主权项

1. A light redirecting fabric, comprising:
a soft and flexible sheet of optically transmissive material; and a plurality of parallel slits formed in a surface of the soft and flexible sheet, wherein each of the plurality of parallel slits comprises a first wall and an opposing second wall that direct incident light, wherein each of the plurality of slits is dimensioned such that incident light received on a surface of the soft and flexible sheet is intercepted and at least partially redirected along a direction of propagation that is different than a direction of incidence, wherein the incident light is at least partially redirected at a bend angle that is greater than an angle of incidence with respect to the surface of the soft and flexible sheet.