An optical system for illuminating a display device by providing substantially telecentric illumination at a display surface of the display device. In one embodiment, a first lens having a first focal length (f1) and a second lens having a second focal length (f2) are separated by a distance of approximately f1 + f2. The first lens receives light from a light source which provides light at a plurality of points of a surface of said light source; at each point, light is emitted in a predetermined pyramidal-like shape which has an axis and which defines an angle. The second lens, which is optically coupled to the first lens, provides light to the display device, which has a light modulating surface. A plurality of points at the light modulating surface receive a plurality of predetermined pyramidal-like shapes of light which are aligned to be parallel.