Method of making daylight redirecting window films employing embedded microstructures

Abstract

A method of making a daylight redirecting window film having a layered structure with a total thickness of less than one millimeter and having at least two optical films bonded together. One of the optical films has a first light redirecting layer disposed on a first side of the film and including a linear array of light redirecting structures configured to reflect light using a total internal reflection and defining a parallel array of narrow channels, and a second light redirecting layers disposed on an opposite second side of the film and including light scattering surface microstructures. The method includes coating a surface of at least one of the films with an optical adhesive, positioning the optical films such that the top portions of the light redirecting structures face inwards, and bonding the films together to form a monolithic multi-layer light redirecting film structure.