摘要:
A head up display includes an image source, collimating optics, and a combiner. The collimating optics are disposed between the combiner and the image source. The combiner receives collimated light from the collimating optics at an input and provides the collimated light to an output. The collimating light travels from the input to the output within the combiner by total internal refraction. An input diffraction grating is disposed in a first area and an output diffraction grating is disposed in a second area. The first area is smaller than the second area.