Envisics Ltd

A method comprising: applying a respective value of a first plurality of values of a first control parameter to each light source of a projector system, wherein each of the first plurality of values of the first control parameter determines an output luminance of a corresponding light source; measuring a first luminance and first colour space coordinates of a light pattern displayed based on the first plurality of values; converting the first luminance and first colour space coordinates to corresponding tristimulus values; calculating therefrom a respective colour luminance value corresponding to each light source; calculating a linear relationship between the first control parameter and each colour luminance value; determining a second plurality of values of the first control parameter based on the linear relationships and a target colour luminance value for each light source; and controlling the plurality of light sources using the second plurality of values.

Systems and methods disclosed herein include, among other aspects, a head-up display comprising an eye-box having a first dimension and a second dimension, where the head-up display is arranged to form first image content in a first image area at a first image area distance from the eye-box and second image content in a second image area at a second image area distance from the eye-box, where the first image area distance is less than the second image area distance and the first image area is at least partially overlapping in the first dimension with the second image area, and where the second image area extends less far in angular space than the first image area in at least one direction of the first dimension.

Systems and methods disclosed herein include, among other aspects, a head-up display comprising an eye-box having a first dimension and a second dimension, where the head-up display is arranged to form first image content in a first image area at a first image area distance from the eye-box and second image content in a second image area at a second image area distance from the eye-box, where the first image area distance is less than the second image area distance and the first image area is at least partially overlapping in the first dimension with the second image area, and where the second image area extends less far in angular space than the first image area in at least one direction of the first dimension.

There is provided a driver for a spatial light modulator comprising a plurality of pixels. The driver is configured to receive a hologram of a picture and drive the spatial light modulator to display the hologram on a group of pixels of the plurality of pixels. The driver is further configured to apply a series of phase offsets to the spatial light modulator displaying the hologram, wherein each phase offset of the series of phase offsets is applied to each pixel of the group of pixels for a respective predetermined period of time.

There is provided a driver for a spatial light modulator comprising a plurality of pixels. The driver is configured to receive a hologram of a picture and drive the spatial light modulator to display the hologram on a group of pixels of the plurality of pixels. The driver is further configured to apply a series of phase offsets to the spatial light modulator displaying the hologram, wherein each phase offset of the series of phase offsets is applied to each pixel of the group of pixels for a respective predetermined period of time.

There is provided a hologram engine for calculating a hologram of a target picture comprising a plurality of image points. The hologram engine is arranged to perform a first accumulation comprising, for a first subset of image points: determining, using a point cloud method, a value for every nth pixel of a display device for displaying the hologram; and determining a value for at least some of the other pixels by performing a first interpolation. n is greater than 1. Each image point of the first subset has an associated diffraction angle for use in the point cloud method, each diffraction angle being less than a maximum diffraction angle of the display device.

A holographic system comprises an image processor, a hologram calculator and a display driver. The image processor is arranged to determine first and second secondary images by sampling the pixel values of a primary image at a regular array of sampling positions. The hologram calculator is arranged to determine a hologram of each secondary image. The display driver is arranged to display each hologram in rapid succession on a display device, first and second times, so as to reconstruct each secondary image from the respective hologram such that respective first and second arrays of image pixels corresponding to the primary image are perceivable. Image pixels of the reconstruction of the second secondary image are interposed between image pixels of the reconstruction of the first secondary image in the first direction.

A picture generating unit comprises a display device arranged to display a hologram of a picture; and spatially modulate light in accordance with the displayed hologram to form a holographic reconstruction of the picture on a replay plane. The holographic reconstruction comprises a picture area and a non-picture area. The picture generating unit comprises an active mask in or downstream of the replay plane, the mask comprising a propagation area arranged to allow propagation of light along a projection axis, and a non-propagation area arranged to prevent propagation of light parallel to the projection axis. The propagation area and the non-propagation area share a boundary adjustable to change one or more physical parameters of the propagation area. The picture generating unit further comprises a drive means arranged to adjust the boundary to change the one or more physical parameters of the propagation area.

A method of calculating a map in real-time includes receiving a calibrated map including a plurality of mappings. Each mapping is for transforming a respective two-dimensional coordinate of an array of two-dimensional coordinates to compensate for distortion at a predetermined temperature. The method includes receiving an array of vectors including a vector for each two-dimensional coordinate. The method includes receiving a current temperature of the holographic projector. The method includes determining a scaling factor based on the difference between the current temperature and the predetermined temperature. The method includes calculating a modified map based on the current temperature by, for each coordinate of the array of two-dimensional coordinates: multiplying the vector that relates to the respective coordinate of the array of two-dimensional coordinates by the scaling factor to output a scaled vector; applying the scaled vector to the respective mapping of the calibrated map; and outputting the modified map.

A method and system for improving the control of a holographic projection system in order to meet, or to attempt to meet, one or more targets or aims for a holographically reconstructed image that is produced by the holographic projection system. The target, or aim, may concern the luminance of part or all of the holographically reconstructed image.