Head-up display

Abstract

There is provided a head-up display having an eye-box comprising a driver monitoring system, picture generating unit and optical system. The driver monitoring system is arranged to illuminate and monitor a driver. The driver monitoring system comprises a first display channel. The picture generating unit is arranged to display a picture on a replay plane. The picture generating unit comprises a second display channel. Each display channel comprises a light source, spatial light modulator and controller. Each light source is arranged to emit light. Each spatial light modulator is arranged to receive light from the respective light source and output spatially-modulated light in accordance with a computer-generated hologram displayed on the spatial light modulator to form a respective light pattern on the replay plane. Each controller is arranged to output the computer-generated hologram to the spatial light modulator. The optical system is arranged to relay each light pattern from the replay plane. The optical system comprises an input, output and at least one mirror. The input is arranged to receive light of each light pattern. The output is arranged to output light of each light pattern. The at least one mirror is arranged to guide light from the input to the output along an optical path. The light pattern formed by the first display channel is an infrared light pattern. Each light pattern is a holographic reconstruction.