Phase modulator redirecting incident light from darker areas to lighter areas of images
AssigneeMTT Innovation Incorporated
InventorsGerwin Damberg, Anders Ballestad
Life of this patent
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Abstract
Undesirably high energy-consumption in illuminating devices can be caused at least in part by wasted (attenuated) light. Optically efficient illumination systems that may be used to project light, including images, use light redirection. Phase modulating devices may be applied to create desired light fields. Some embodiments provide dual or multiple modulation display or projection systems in which some or all of the modulators not only attenuate amplitude, but also amplify amplitude, or change the phase, frequency and polarization of the light provided by the light source.
Claims24
An image projection system to display images specified by image data, the image data specifying luminance that varies from place to place on the images such that the images have darker areas and lighter areas, the projection system comprising:
- a phase modulator comprising a number of elements that are controllable to impart a selective phase delay in light passing through each element;
- a control circuit configured to control the elements of the phase modulator to create a lens with a phase pattern that directs incident light to form a light field corresponding to the varying luminance of the image data and to focus the directed light onto an image plane;
- a light source arranged to illuminate the phase modulator with the incident light;
- and
- optics arranged to project light from the image plane onto a surface
- wherein:
- the control circuit is configured to determine a two-dimensional pattern of phase delay values for the phase modulator based on a model describing an amount of deflection caused by a difference in phase of neighboring regions of the phase modulator when illuminated by the incident light.
Dependencies are inferred from the claim text.