Curved light controlling structures

A privacy film for a curved display screen has a curved cross-section when no force is applied. The film includes alternating transparent 402 and opaque 403 layers, each extending across the film and each parallel to the other transparent and opaque layers when no force is applied. The transparent layers may include one or more of acrylic, polycarbonate, polyethylene terephthalate (PET), and a resin. The privacy film may be applied to a curved display screen with a lesser radius of curvature by bending the film during application. A privacy film is manufactured for a curved display screen by providing a block 401 of flat transparent and opaque layers and cutting 404 the block to form a film with a curved cross-section when no force is applied. Each transparent and opaque layer extends across the film which is polished or has a transparent coating applied to the cut surfaces. The block may be provided by gluing transparent layers together using a mixture of an adhesive and a pigment which form the opaque layers. The block may also be provided by pouring and curing/setting, first and second liquids to form solid first and second layers and repeating this to form further layers.