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US 12,591,136 B2Granted
Hologram calculation
AssigneeEnvisics Ltd
InventorsTimothy Smeeton, Daniel Burnham, Jamieson Christmas
Life of this patent
Estimating the term…
Abstract
Systems and methods of determining a hologram of an image for a system comprising a display device and viewing system are disclosed. Some embodiments implement a multi-stage procedure comprising (i) determining a first complex light field at an entrance pupil of the viewing system, (ii) determining a second complex light field at a sensor plane of a sensor of the viewing system, (iii) determining a third complex light field at the entrance pupil, and (iv) determining a fourth complex light field at the display plane. Some embodiments include extracting a hologram from a data set corresponding to the fourth complex light field.
Claims20
A method of determining a hologram of a target image for a system comprising a display device arranged to display the hologram at a hologram plane and a viewing system that comprises an entrance pupil, a lens, and a sensor, wherein the viewing system is arranged to view the hologram through a pupil expander that provides a plurality of light propagation paths from the display device to viewing system, the method comprising:
- a first stage, for a first light propagation path, comprising determining a first complex light field at the entrance pupil of the viewing system, wherein the first complex light field results from propagation of light from the hologram plane of the display device, along the first light propagation path, to the entrance pupil, and cropping the light field of the first light propagation path in accordance with at least one of a size, a shape, or a position of the entrance pupil to form the first complex light field;
- a second stage comprising determining a second complex light field at a sensor plane of the sensor of the viewing system, wherein the second complex light field results from propagation of light of the first complex light field from the entrance pupil to the sensor, via the lens of the viewing system, and replacing an amplitude component of the complex light field that arrives at the sensor plane with an amplitude component that is based on the amplitude component of the target image;
- a third stage comprising determining a third complex light field at the entrance pupil, wherein the third complex light field results from reverse propagation of light of the second complex light field from the sensor plane back through the lens and cropping in accordance with the entrance pupil;
- a fourth stage comprising determining a fourth complex light field at the display plane, wherein the fourth complex light field results from reverse propagation of light of the third complex light field back along the first light propagation path and cropping the propagated light, at the hologram plane, in accordance with at least one of the size or position of a pixel area of the display device;
- and
- a fifth stage comprising extracting a hologram from a data set corresponding to the fourth complex light field.
3 more elements
A hologram engine arranged to determine a hologram of a target image for viewing using a head-up display, wherein the head-up display comprises:
- a display device arranged to display the hologram at a hologram plane;
- and
- a pupil expander arranged to receive light spatially modulated in accordance with the hologram, wherein the hologram engine is arranged to:
- determine a first complex light field at an entrance pupil of a viewing system, wherein a plurality of light propagation paths of the pupil expander are defined between the hologram plane of the display device and the entrance pupil, wherein the first complex light field results from propagation of light along a first light propagation path, and cropping the light field of the first light propagation path in accordance with at least one of a size, a shape, or a position of the entrance pupil, to form the first complex light field;
- determine a second complex light field at a sensor plane of a sensor of the viewing system, wherein the second complex light field results from the propagation of light of the first complex light field from an entrance aperture through a lens of the viewing system and replacing an amplitude component of the complex light field that arrives at the sensor plane with an amplitude component that is based on the amplitude component of the target image;
- determine a third complex light field at the entrance pupil, wherein the third complex light field results from reverse propagation of light of the second complex light field from the sensor plane back through the lens and cropping in accordance with the entrance pupil;
- determine a fourth complex light field at the hologram plane, wherein the fourth complex light field results from reverse propagation of light of the third complex light field back along the first light propagation path and cropping the propagated light, in accordance with at least one of the size or the position of a pixel area of the display device;
- and
- extract the hologram from a data set corresponding to the fourth complex light field.
6 more elements
A system comprising:
- a display device configured to display a hologram at a hologram plane;
- a viewing system that comprises an entrance pupil, a lens, and a sensor, wherein the viewing system is configured to view the hologram through a pupil expander configured to provide a plurality of light propagation paths from the display device to viewing system;
- one or more processors;
- and
- tangible, non-transitory computer-readable media comprising program instructions executable by the one or more processors such that the system is configured to determine the hologram of a target image according to a method comprising:
- determining, for a first light propagation path, a first complex light field at the entrance pupil of the viewing system, wherein the first complex light field results from propagation of light from the hologram plane of the display device along the first light propagation path to the entrance pupil, and cropping the light field of the first light propagation path in accordance with at least one of a size, a shape, or a position of the entrance pupil of the viewing system, to form the first complex light field;
- determining a second complex light field at a sensor plane of the sensor of the viewing system, wherein the second complex light field results from propagation of light of the first complex light field from the entrance pupil to the sensor, via the lens of the viewing system, and replacing an amplitude component of the complex light field that arrives at the sensor plane with an amplitude component that is based on the amplitude component of the target image;
- determining a third complex light field at the entrance pupil, wherein the third complex light field results from reverse propagation of light of the second complex light field from the sensor plane back through the lens and cropping in accordance with the entrance pupil;
- determining a fourth complex light field at the display plane, wherein the fourth complex light field results from reverse propagation of light of the third complex light field back along the first light propagation path and cropping the propagated light in accordance with at least one of the size or position of a pixel area of the display device;
- and
- extracting a hologram from a data set corresponding to the fourth complex light field.
8 more elements
Dependencies are inferred from the claim text.