Illumination system and method

A method for providing light illumination comprising:

• providing incident light from a source thereof to a spatial light modulator of an illumination system, wherein
• the incident light received by the spatial light modulator has a ratio of an intensity of light having a first optical property state with respect to an optical property to an intensity of light having a second optical property state with respect to the optical property, the second optical property state being different from the first optical property;
• outputting light, by the spatial light modulator, for providing the illumination, the output light comprising a first component and a second component, wherein
• the spatial light modulator modulates incident light having the second optical property state without substantially modulating incident light having the first optical property state to output light comprising
• the first component corresponding to incident light of the first optical property state that is output without modulation by the spatial light modulator to provide the light beam for illumination of the scene, and
• the second component corresponding to incident light having the second optical property state that is spatially-modulated according to a hologram displayed by the spatial light modulator and output by the spatial light modulator to contribute to the light beam, and thereby to provide light contributing to the illumination of the scene, wherein the hologram is dynamically changeable;
• and
• performing a holographic reconstruction of the output light of the second component to provide the light contributing to the illumination of the scene, wherein substantially no holographic reconstruction results from the output light of the first component that provides the light beam for illumination of the scene,
• the method further comprising:
• controlling the illumination system by adjusting a ratio of intensity of incident light received by the spatial light modulator having the first optical property state to intensity of incident light received by the spatial light modulator having the second optical property state to adjust a proportion of the light output by the spatial light modulator corresponding to the second component, such that the illumination system
• operates in a first illumination mode, in which the illumination system is controlled such that the spatial light modulator receives incident light having a first ratio of intensity of light having the first optical property state to intensity of light having the second optical property state, and
• operating in a second illumination mode, in which the illumination system is controlled such that the spatial light modulator receives incident light having a second ratio of intensity of light having the first optical property state to intensity of light having the second optical property state, the second ratio being greater than the first ratio, so that the second component output by the spatial light modulator contributes to the light beam.

An illumination system arranged to output a light beam for illuminating a scene, comprising:

• a spatial light modulator arranged to receive incident light, and to output light comprising a first component and a second component;
• and
• a control device operable to control the proportion of light output by the spatial light modulator that corresponds to the second component by controlling a ratio of an intensity of incident light received by the spatial light modulator having a first optical property state with respect to an optical property to an intensity of incident light received by the spatial light modulator having a second optical property state with respect to the optical property, the second optical property state being different from the first optical property state,
• wherein
• the first component of the output light comprises incident light having the first optical property state that is output without modulation by the spatial light modulator to provide the light beam for illumination of the scene, and
• the second component of the output light comprises incident light having the second optical property state that is spatially-modulated according to a hologram displayed by the spatial light modulator and output by the spatial light modulator to contribute to the light beam, and thereby to contribute to the illumination of the scene;
• wherein the hologram is dynamically changeable;
• wherein
• the optical system is arranged to form a holographic reconstruction of the output light of the second component to provide the light contributing to the illumination of the scene, and
• substantially no holographic reconstruction results from the output light of the first component;
• and
• wherein the illumination system is arranged to operate in first and second illumination modes, wherein
• in the first illumination mode, the control device is adjusted such that the spatial light modulator receives incident light having a first ratio of intensity of light having the first optical property state to intensity of light having the second optical property state, and
• in the second illumination mode, the control device is adjusted such that the spatial light modulator receives incident light having a second ratio of intensity of light having the first optical property state to intensity of light having the second optical property state, the second ratio being greater than the first ratio, so that the second component output by the spatial light modulator contributes to the light beam.