US 12,346,067 B2
Illumination system and method
Ian Bledowski, Milton Keynes (GB); Konstantin Deichsel, Milton Keynes (GB); Neil Collings, Milton Keynes (GB); and Jamieson Christmas, Milton Keynes (GB)
Assigned to Envisics Ltd, Milton Keynes (GB)
Appl. No. 17/253,575
Filed by Envisics Ltd, Milton Keynes (GB)
PCT Filed Jul. 26, 2019, PCT No. PCT/EP2019/070194
§ 371(c)(1), (2) Date Dec. 17, 2020,
PCT Pub. No. WO2020/025480, PCT Pub. Date Feb. 6, 2020.
Claims priority of application No. 1812590 (GB), filed on Aug. 2, 2018; and application No. 1812593 (GB), filed on Aug. 2, 2018.
Prior Publication US 2021/0149341 A1, May 20, 2021
Int. Cl. G03H 1/22 (2006.01); G03H 1/02 (2006.01); G03H 1/08 (2006.01)
CPC G03H 1/2294 (2013.01) [G03H 1/024 (2013.01); G03H 1/0841 (2013.01); G03H 1/2205 (2013.01); G03H 2001/0212 (2013.01); G03H 2222/13 (2013.01); G03H 2222/15 (2013.01); G03H 2222/20 (2013.01); G03H 2222/31 (2013.01); G03H 2223/24 (2013.01); G03H 2225/33 (2013.01); G03H 2240/42 (2013.01); G03H 2240/51 (2013.01)] 16 Claims
OG exemplary drawing
 
1. An illumination system arranged to output a light beam for illuminating a scene, comprising:
a source of incident light;
a spatial light modulator arranged to receive the incident light from the source thereof, and to output light comprising a first component and a second component, the spatial light modulator being arranged to display a dynamically-changeable hologram,
wherein
the first component comprises incident light that is output without modulation by the spatial light modulator to provide the light beam for illumination of the scene, the incident light that is output without modulation having a first optical property state with respect to an optical property, and
the second component comprises incident light that is spatially-modulated according to the 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, the incident light that is output with spatially-modulation being incident 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 state;
a light tuning device in the path of the incident light to the spatial light modulator; and
a control device operable to control the proportion of light output by the spatial light modulator that corresponds to the second component by adjusting the light tuning device to control a ratio of an intensity of incident light received by the spatial light modulator having the first property optical to an intensity of incident light received by the spatial light modulator having the second optical property state,
wherein
the illumination 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 light tuning 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 light tuning 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.