G03H2222/22

Beam divergence and various collimators for holographic or stereoscopic displays
10295959 · 2019-05-21 · ·

A holographic display with an illumination device, an enlarging unit and a light modulator. The illumination device includes at least one light source and a light collimation unit, the light collimation unit collimates the light of the at least one light source and generates a light wave field of the light that is emitted by the light source with a specifiable angular spectrum of plane waves, the enlarging unit is disposed downstream of the light collimation unit, seen in the direction of light propagation, where the enlarging unit includes a transmissive volume hologram realizing an anamorphic broadening of the light wave field due to a transmissive interaction of the light wave field with the volume hologram, and the light modulator is disposed upstream or downstream of the anamorphic enlarging unit, seen in the direction of light propagation.

METHOD OF COMPUTING A HOLOGRAM FOR RECONSTRUCTING AN OBJECT USING A DISPLAY DEVICE
20190137933 · 2019-05-09 ·

A method of computing a hologram for reconstructing an object using a display device. The display device enables a holographic reconstruction of the object. The display device includes a light source and an optical system to illuminate a hologram-bearing medium being encodable with the hologram. The method includes the steps of: (a) computing the hologram by determining the wavefronts at an approximate observer eye position that would be generated by a real version of the object to be reconstructed; and (b) encoding the computed hologram in the hologram-bearing medium.

ILLUMINATION DEVICE
20190094803 · 2019-03-28 ·

The invention refers to an Illumination device for illuminating a spatial light modulator device. Sub-holograms are used for encoding a hologram into the spatial light modulator device. The Illumination device comprises at least one light source for emitting light for illuminating the spatial light modulator device and a beam shaping unit. The beam shaping unit provides a flat-top plateau-type distribution of an absolute value of a complex degree of mutual coherence of the light in a plane of the spatial light modulator device to be illuminated. The flat-top plateau-type distribution of the absolute value of the complex degree of mutual coherence has a shape that is at least similar to a shape of the largest sub-hologram used for encoding of object points into the spatial light modulator device.

Viewer tracking in a projection system
10120335 · 2018-11-06 · ·

A method for displaying a hologram to a variable direction including using circuitry to determine a direction from a holographic projector to a viewer for projecting a hologram to a viewer, and projecting a hologram in the determined direction, in which the projecting the hologram includes reflecting from a same mirror as the determining the direction of the viewer, and the circuitry controls the projecting the hologram to a direction corrected for a difference in direction between a projecting unit and a tracking unit relative to the mirror. Related apparatus and methods are also described.

HOLOGRAPHIC DISPLAY
20180217554 · 2018-08-02 ·

Disclosed is a holographic display including a spatial light modulator (SLM) with pixels, the SLM pixels being on a substrate, the SLM including circuitry which is on the same substrate as the SLM pixels, the circuitry operable to perform calculations which provide an encoding of the SLM.

Illumination device
12117770 · 2024-10-15 · ·

An illumination device for illuminating a spatial light modulator device. Sub-holograms are used for encoding a hologram into the spatial light modulator device. The Illumination device includes at least one light source for emitting light for illuminating the spatial light modulator device and a beam shaping unit. The beam shaping unit provides a flat-top plateau-type distribution of an absolute value of a complex degree of mutual coherence of the light in a plane of the spatial light modulator device to be illuminated. The flat-top plateau-type distribution of the absolute value of the complex degree of mutual coherence has a shape that is at least similar to a shape of the largest sub-hologram used for encoding of object points into the spatial light modulator device.

Method of computing a hologram for reconstructing an object using a display device
09989920 · 2018-06-05 · ·

A method of computing a hologram for reconstructing an object using a display device. The display device enables a holographic reconstruction of the object. The display device includes a light source and an optical system to illuminate a hologram-bearing medium being encodable with the hologram. The method includes the steps of: (a) computing the hologram by determining the wavefronts at an approximate observer eye position that would be generated by a real version of the object to be reconstructed; and (b) encoding the computed hologram in the hologram-bearing medium.

METHOD FOR DETERMINING THE STATE OF A CELL

A method for identifying a state of a cell contained in a sample, including: illuminating the sample using a light source by producing an incident light wave propagating toward the sample; then acquiring, using a matrix-array photodetector, an image of the sample, the sample being placed between the light source and the matrix-array photodetector such that the matrix-array photodetector is exposed to a light wave resulting from interference between the incident light wave and a diffraction wave produced by each cell; applying a numerical reconstruction algorithm to the image acquired by the matrix-array photodetector, to estimate a characteristic quantity of the light wave reaching the matrix-array detector, at a plurality of distances from the matrix-array photodetector. The value of the characteristic quantity, or its variation as a function of distance, allows the state of the cell to be determined from among predetermined states.

DIGITAL HOLOGRAPHIC IMAGE-TAKING APPARATUS
20180107159 · 2018-04-19 · ·

Provided is a digital holographic image-taking apparatus, including: an illumination portion (10) having a light emission surface (14D) for emitting illumination light toward an object (1), the illumination light having a specific wavelength in a coherent plane waveform; and an image sensor (50) having an pixel array (51) including two-dimensionally arranged pixels, the image sensor (50) capturing an interference pattern generated based on the illumination light having acted on the object (1), in which the following conditional expression is satisfied: 0.0000001<Z.sup.2/S<16, where S represents the area of the light emission surface (14D), and Z represents the distance from the light emission surface (14D) to the pixel array (51).

Holographic display

Disclosed is a holographic display including a spatial light modulator (SLM) with pixels, the SLM pixels being on a substrate, the SLM including circuitry which is on the same substrate as the SLM pixels, the circuitry operable to perform calculations which provide an encoding of the SLM.