Patent attributes
A sheet-form light-redirecting optical article for illuminating building interiors with sunlight. At least one embodiment comprises a sheet of optically transmissive rigid material, preferably Poly(methyl methacrylate), in which a plurality of deep and narrow parallel channels are formed and arranged in two perpendicular arrays. Each channel has opposing walls configured for reflecting light by means of a Total Internal Reflection (TIR). At least a portion of off-axis rays incident onto the surface of the sheet is redirected by the TIR walls of the light-guiding channels. At least one embodiment comprises a grid formed by intersecting specular reflectors and further comprises a light diffusing element optically coupled to the grid. Disclosed also are a method for making the intersecting arrays of light-redirecting channels.