An illumination apparatus using a coherent light source, comprising: a coherent light source that generates a coherent light beam, a microlens array including a collection of a large number of independent lenses; and a light beam scanning device that irradiates the light beam onto the microlens array and carries out scanning so that an irradiation position and an irradiation direction of the light beam on the microlens array changes with time. Each of the independent lenses included in the microlens array has a function of refracting light irradiated from the light beam scanning device and forming an irradiation region on a light receiving surface. The light receiving surface is not a refractive element, and is configured so that irradiation regions formed by the independent lenses become substantially a same common region on the light receiving surface. The irradiation regions being irradiated by light which is refracted by the independent lenses.

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.

An apparatus for suppressing electron/hole recombination includes a photonic device that generates electron/hole pairs responsive to a light beam interacting with the photonic device. An orbital angular momentum (OAM) generation device is located to impart an orbital angular momentum to a light beam before the light beam interacts with the photonic device. The electron/hole pair recombination generated from an OAM imparted light beam is less than electron/hole pair recombination of a non-OAM imparted light beam.

Example embodiments relate to methods and imaging systems for holographic imaging. One embodiment includes a method for holographic imaging of an object. The method includes driving a laser using a current which is below a threshold current of the laser. The method also includes illuminating the object using illumination light output by the laser. Further, the method includes detecting an interference pattern formed by object light, having interacted with the object, and reference light of the illumination light.

A method for irradiating a medium includes irradiating the medium with an electromagnetic wave which is scattered in the medium and modulated in frequency at a position in the medium; obtaining information corresponding to an interference pattern generated by interference between the modulated electromagnetic wave and a reference wave; and generating a phase conjugate wave, based on the obtained information, which irradiates the medium.

Three-Dimensional (3D) display device and method are disclosed. The device can include: a Light-Emitting Diode (LED) display, configured to display an image; a light path control structure including a multilayer pinhole type structure, configured to control emitting directions of light paths of the image to form 3D light field information, wherein multiple groups of pinhole arrays are arranged on each layer of the pinhole type structure; and a holographic function screen, configured to perform diffusion imaging on the 3D light field information to form a 3D image, wherein the LED display, the light path control structure and the holographic function screen are sequentially configured. The technical problems of the related art are solved.

A holographic observation method includes: casting a light beam generated by driving a semiconductor laser light source with an electric current with an alternating-current component superimposed or a light beam having a predetermined spectral width and predetermined spectral intensity to have predetermined coherency to an observation object; forming a hologram by causing a light beam transmitted through or reflected by the observation object to interfere with a reference light beam; and obtaining information on the observation object by performing image processing on the hologram.

A beam steering backlight unit provides a hologram image to multiple viewing positions and a holographic display apparatus includes the beam steering backlight unit. The backlight unit includes a light source array comprising a plurality of two-dimensionally arranged light sources and a micro lens array arranged to face the light source array and comprising a plurality of two-dimensionally arranged micro lenses. The light source array includes a plurality of light source blocks each corresponding to a respective one of the plurality of micro lenses, wherein a plurality of the light sources are arranged in each of the plurality of light source blocks. The light source array is configured to select and turn on only those light sources of the plurality of light sources respectively disposed in a same position in each of the plurality of light source blocks and turn off the other light sources.

A hologram display apparatus and a hologram display method are provided. The hologram display apparatus includes a controller and a display device. The controller is configured to obtain plural grayscale values G.sub.i of an image of a to-be-displayed object, generate plural display sub-image codes Q.sub.j according to the plurality of grayscale values G.sub.i and transmit the plurality of display sub-image codes Q.sub.j to the display device, where i=1, 2, . . . , m, j=1, 2, . . . N, each of m and N is a positive integer. The display device is configured to generate and display plural sub-holograms according to the plurality of display sub-image codes, a quantity of the plurality of sub-holograms being equal to that of the plurality of display sub-image codes, such that the plurality of sub-holograms are superimposed to generate a hologram of the image of the to-be-displayed object in human eyes.

Methods, apparatus, devices, and systems for three-dimensional (3D) displaying objects are provided. In one aspect, a method includes obtaining data including respective primitive data for primitives corresponding to an object, determining an electromagnetic (EM) field contribution to each element of a display for each of the primitives by calculating an EM field propagation from the primitive to the element, generating a sum of the EM field contributions from the primitives for each of the elements, transmitting to each of the elements a respective control signal for modulating at least one property of the element based on the sum of the EM field contributions, and transmitting a timing control signal to an illuminator to activate the illuminator to illuminate light on the display, such that the light is caused by the modulated elements of the display to form a volumetric light field corresponding to the object.