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.

A holographic display apparatus and a display method thereof are disclosed. The holographic display apparatus includes: a backlight source configured to supply a coherent reference light; an optical switch configured to modulate light wave amplitude information of the coherent reference light; and a phase control plate configured to modulate light wave phase information of the coherent reference light, wherein the phase control plate and the optical switch are arranged on a light exit side of the backlight source.

A backlight module, a spatial light modulator, a holographic display device and a holographic display method therefor are disclosed. The backlight module includes: a light source; an optical conversion element arranged to face the light source and configured to convert a light beam emitted by the light source into coherent collimated light; and a light switch layer disposed at a side of the optical conversion element away from the light source. The optical conversion element includes a plurality of sub-optical conversion regions. The light switch layer includes a plurality of sub-light switches, the plurality of sub-light switches and the plurality of sub-optical conversion regions being disposed in one-to-one correspondence.

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.

A display method lets a display beam to propagate in a transparent substrate while internally reflected repeatedly and lets the display beam partly emit out of the transparent substrate every time the display beam is internally reflected, thereby emitting display beams from almost entirety of a surface of the transparent substrate. The display beam is produced holographically. A display apparatus includes a spatial phase modulator that produces a display beam, a transparent substrate in which the display beam is internally reflected repeatedly to propagate in it, and a splitter that lets the display beam partly emit out of the transparent substrate every time the display beam is internally reflected.

A method of forming a rarefied hologram for video imaging and 3D lithography by using an MEMS/SLM with a plurality of pixels on the surface at a fixed distance from the retina of the viewer eye. The method consists of providing an initial desired image, which has to be holographically reproduced by the MEMS/SLM as a remote virtual 3D image visible by the viewer's eye. The desired image is coded in a special manner and mapped by encoding and calculating only a part of the initial desired image. The operations of the pixels are controlled in accordance with the code for generation of the holographic pattern. Since only a part of a holographic pattern of the image is encoded and calculated, it becomes possible to reduce the calculation time and decrease parasitic light scattering.

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.

Apparatus and methods for Coherent Diffractive Imaging with multiple, simultaneous, spatially distinct beams chosen and configured to isolate incoherent sums of beam diffraction such that interference between the multiple beams is not present in the data prior to computationally reconstructing the image. This is accomplished through selecting the multiple beams to be non-interfering modes, or through designing the apparatus such that the interference is not recorded, or through processing the collected data to filter the interference before reconstructing the image.

A holographic projector comprising a display device, a laser diode chip and at least one optic. The display device is arranged to display a hologram of a picture. The laser diode chip comprising a plurality of emitters. Each emitter is arranged to form a respective beamlet. The beamlets are incoherent with each other such that they form different speckle patterns. The at least one optic is arranged to receive the plurality of beamlets and form a continuous beam in which beamlets of the plurality of beamlets at least partially overlap. The holographic projector is arranged to illuminate the hologram with the continuous beam and form a holographic reconstruction of the picture. The speckle patterns of the beamlets reduce noise in the holographic reconstruction through addition of intensity rather than amplitude and phase.

An image capturing apparatus (500) capable of performing three-dimensional tomography of an object by digital holography, includes a splitting element (502) which splits a light beam emitted from a light source into an object light beam and a reference light beam, an illumination system (503) which controls a plurality of object light beams that are generated from the object light beam and that move in directions different from each other to be incident on the object simultaneously, a composite element (507) which causes the plurality of object light beams to interfere with the reference light beam, an image sensor (508) which acquires hologram generated by interference of each of the plurality of light beams with the reference light beam, and a controller (509) which controls the illumination system so that the plurality of object light beams interfere with each other on the image sensor.