A holographic head-up display device includes: a light source portion that emits coherent light; an optical modulation portion that modulates the coherent light; a relay optical system that focuses the modulated light; a filter mirror that includes a reflection area disposed at a focal position of the relay optical system and reflecting light incident through the relay optical system and an absorption area disposed at the periphery of the reflection area and absorbing light incident through the relay optical system; and a transflective mirror that partially transmits and partially reflects light reflected by the filter mirror.

A holographic display apparatus for providing an expanded viewing window includes a spatial filter configured to separate a plurality of holographic images generated by the hologram pattern displayed on the spatial light modulator from a plurality of lattice spots generated by a physical structure of the spatial light modulator. The spatial filter includes a plurality of color filters or a plurality of dichroic mirrors separating a first color image, a second color image, and a third color image from a first color lattice spot, a second color lattice spot, and a third color lattice spot.

The invention relates to a display device for representing two-dimensional and/or three-dimensional scenes. The display device comprises at least one illumination device to emit sufficiently coherent light, at least one spatial light modulation device, at least one optical system and a tracking device. A hologram is encoded into the at least one spatial light modulation device by means of a single-parallax encoding. The at least one optical system is provided to generate at least one virtual visibility region at the position of an eye of an observer. The encoding direction of the hologram on the spatial light modulation device is modifiable by means of the tracking device.

Differential Holography technology measures the amplitude and/or phase of, e.g., an incident linearly polarized spatially coherent quasi-monochromatic optical field by optically computing the first derivative of the field and linearly mapping it to an irradiance signal detectable by an image sensor. This information recorded on the image sensor is then recovered by a simple algorithm. In some embodiments, an input field is split into two or more beams to independently compute the horizontal and vertical derivatives (using amplitude gradient filters in orthogonal orientations) for detection on one image sensor in separate regions of interest (ROIs) or on multiple image sensors. A third unfiltered beam recorded in a third ROI directly measures amplitude variations in the input field to numerically remove its contribution as noise before recovering the original wavefront using a numerical in algorithm. When combined, the measured amplitude and phase constitute a holographic recording of the incident optical field.

A holographic head-up display device has a light source portion that emits coherent light; an optical modulation portion that modulates the coherent light; a relay optical system that focuses the modulated light; a filter minor that has a reflection area at a focal position of the relay optical system and reflecting light incident through the relay optical system and an absorption area at the periphery of the reflection area and absorbing light incident through the relay optical system; and a transflective mirror that partially transmits and partially reflects light reflected by the filter minor.

A method of holographic projection includes projecting at least one calibration image. The method includes performing the following steps for each calibration image in order to determine a plurality of displacements vectors at a respective plurality of different locations on the replay plane: projecting the calibration image onto the replay plane using a first colour holographic channel by displaying a first hologram on a first spatial light modulator and illuminating the first spatial light modulator with light of the first colour; projecting the calibration image onto the replay using a second colour holographic channel by displaying a second hologram on a second spatial light modulator and illuminating the second spatial light modulator with light of the second colour, the first and second hologram corresponding to the calibration image; determining the displacement vector between the light spot formed by the first colour holographic channel and the light spot formed by the second colour holographic channel; and pre-processing an image for projection using the second colour holographic channel in accordance with the plurality of determined displacement vectors.

There is provided a lighting device arranged to produce a controllable light beam for illuminating a scene. The device comprises an addressable spatial light modulator arranged to provide a selectable phase delay distribution to a beam of incident light. The device further comprises Fourier optics arranged to receive phase-modulated light from the spatial light modulator and form a light distribution. The device further comprises projection optics arranged to project the light distribution to form a pattern of illumination as said controllable light beam.

There is provided a lighting device arranged to produce a controllable light beam for illuminating a scene. The device comprises an addressable spatial light modulator arranged to provide a selectable phase delay distribution to a beam of incident light. The device further comprises Fourier optics arranged to receive phase-modulated light from the spatial light modulator and form a light distribution. The device further comprises projection optics arranged to project the light distribution to form a pattern of illumination as said controllable light beam.

A holographic display apparatus for providing an expanded viewing window includes a spatial filter configured to separate a plurality of holographic images generated by the hologram pattern displayed on the spatial light modulator from a plurality of lattice spots generated by a physical structure of the spatial light modulator. The spatial filter includes a plurality of color filters or a plurality of dichroic mirrors separating a first color image, a second color image, and a third color image from a first color lattice spot, a second color lattice spot, and a third color lattice spot.

A projection system includes a light source configured to emit a light in response to an image data, a phase light modulator configured to receive the light from the light source and to apply a spatially-varying phase modulation on the light, thereby generating a projection light and steering the light on a reconstruction field, wherein the reconstruction field is a complex plane on which a reconstruction image is formed, and a controller configured to control the light source, control the phase light modulator, initialize (401) the reconstruction field to an initial value, and iteratively for each of a plurality of subframes within a frame of the image data: set (402) the reconstruction field to the initial value for the first iteration or set (402) the reconstruction field to a subsequent-iteration reconstruction field value for any subsequent-iteration, map (403) the reconstruction field to a modulation field, wherein the modulation field is a complex plane of the phase light modulator which modulates a phase of the light, set (404) an amplitude of the modulation field to a predetermined value, and map (405) the modulation field with the amplitude set to the predetermined value, to a subsequent-iteration reconstruction field, wherein the controller is further configured to provide (408) a phase control signal based on the modulation field mapped with the last iteration to the phase light modulator.