Head-up display

A head-up display for a vehicle arranged to be operated by a driver having an eye positioned within an eye-box, the head-up display comprising:

• a driver monitoring system arranged to illuminate and monitor a driver, wherein the driver monitoring system comprises an infrared display channel comprising:
• an infrared light source arranged to emit infrared light;
• and
• a first spatial light modulator arranged to display a light-modulation distribution comprising computer-generated first hologram, the first spatial light modulator being arranged to receive the infrared light from the infrared light source and output spatially-modulated light in accordance with the first hologram to form an infrared light pattern on a replay plane;
• and
• a first controller arranged to output the first light-modulation distribution to the first spatial light modulator:
• an infrared camera arranged to obtain infrared images of the driver in the eye-box;
• and
• an image processor arranged to receive captured images of the driver from the infrared camera and to determine an absolute position of the driver in the eye-box and/or a change in position of the driver in the eye-box and output to the first controller data representative of the position of the driver in the eye-box,
• wherein the first controller is arranged to change the first light-modulation distribution based on the data representative of the position of the driver in the eye-box;
• a picture generating unit arranged to display a picture on the replay plane, wherein the picture generating unit comprises a visible light display channel, wherein the visible light display channel comprises:
• a visible light source arranged to emit visible light;
• a second spatial light modulator arranged to display a second hologram, the second hologram being computer-generated, and to receive the visible light from the visible light source and output spatially-modulated light in accordance with the computer-generated second hologram displayed on the second spatial light modulator to form a visible light pattern on the replay plane;
• and
• a controller arranged to output a second light-modulation distribution comprising the computer-generated hologram to the second spatial light modulator;
• and
• an optical system arranged to relay the infrared light pattern and the visible light pattern from the replay plane to an optical combiner arranged to direct the relayed light to the eye-box, to provide to the eye-box a combined view that is a combination of a view of the relayed visible light with a view of an area viewable by driver from the eye-box through the optical combiner, such that the infrared light pattern illuminates the driver in the eye-box to provide an illuminated area for an image of the driver obtained by the infrared camera and such that the visible light pattern is visible within the eye-box, wherein the optical system is configured to receive the infrared light pattern and the visible light pattern from the replay plane and to output light of the infrared light pattern and light of the visible light pattern to the optical combiner;
• and comprises:
• at least one mirror arranged to guide light from the replay plane to the optical combiner along an optical path.