A method includes selecting a period for a volume Bragg grating (VBG) such that a spectral selectivity of the VBG is at least as wide as a spectral width of a broadband light beam that is to be spatially transformed, selecting a desired beam transformation for the broadband light beam, passing a first light beam from a recording light source through an optical device to a volume holographic recording medium where the optical device is configured to induce the desired beam transformation, directing a second light beam from the recording light source to the recording medium, and converging the first light beam and the second beam at a recording angle such that a spatial refractive index modulation profile is recorded in the recording medium that provides the VBG with the selected period, and a phase profile is embedded in the VBG that induces the desired beam transformation for each spectral component within a spectral width of the VBG.

A method of manufacturing a Volume Bragg Grating (VBG) is provided, comprising providing a cylindrical bulk medium made of a transparent glass material and having a central axis along a longitudinal direction, and inscribing an interference pattern in the cylindrical bulk medium. The interference pattern has a plurality of grating fringe elements distributed along a line parallel to the central axis. The method further includes rotating the cylindrical bulk medium about the central axis during said inscribing, thereby azimuthally extending the grating fringes elements. There is further provided a VBG manufactured according to such a method, the use of such a VBG in a CPA system of cladding-pumped fiber laser.

The present disclosure discloses a method and apparatus for preparing a femtosecond optical filament interference direct writing volume grating/chirped volume grating. The method is characterized in that optical filaments are formed in glass by using femtosecond pulse laser, and plasma is controlled to quickly scan in the glass and etch a volume grating or chirped volume grating structure by adjusting the focal length of convex lens, laser energy and movement of motor machine. The apparatus includes a femtosecond pulse laser module, a pulse chirp management module, a pulse time domain shaping module, a laser separation and interference module, a glass volume grating processing platform module and a camera online imaging module.

The present disclosure discloses a method and apparatus for preparing a femtosecond optical filament interference direct writing volume grating/chirped volume grating. The method is characterized in that optical filaments are formed in glass by using femtosecond pulse laser, and plasma is controlled to quickly scan in the glass and etch a volume grating or chirped volume grating structure by adjusting the focal length of convex lens, laser energy and movement of motor machine. The apparatus includes a femtosecond pulse laser module, a pulse chirp management module, a pulse time domain shaping module, a laser separation and interference module, a glass volume grating processing platform module and a camera online imaging module.

A volume Bragg grating (VBG) containing one or more controlled phase profiles holographically embedded therein that is operable over a broad wavelength range, methods for making such controlled phase profile-embedded VBGs, and applications thereof.

The present disclosure relates to a holographic reproducing apparatus comprising: a light source configured to supply a reproducing light beam to be incident to a photorefractive crystal, wherein the photorefractive crystal has holographic images recorded therein in a plurality of different angles respectively; a reflective mirror configured to reflect the reproducing light beam emitted from the light source to the photorefractive crystal; and a driving mechanism connected to the reflective mirror and configured to drive the reflective mirror to move on a plane elliptical arc, the plane elliptical arc is defined by using the light source and the photorefractive crystal as two mathematical focuses and using a predetermined constant, so that an incident angle of the reproducing light beam to be incident to the photorefractive crystal varies to form a plurality of reproducing light beams in different angles to be incident to the photorefractive crystal in sequence.

A display system and a display method of the display system are provided, and the display system includes: at least one holographic image display device, each holographic image display device is configured to display a holographic image of a scene; at least one reflection image display device, each reflection image display device is configured to display a reflection image of a scene; the at least one holographic image display device and the at least one reflection image display device are arranged in parallel, and the holographic image and the reflection image are displayed to achieve a stereoscopic display in a display side of the display system.

An image photography play method which is suited to playing a stereoscopic video. The image photography method includes: a step of forming a hologram pattern from a reference light and a subject light; a step of digitally processing the obtained hologram pattern; a step of writing the digitized hologram pattern as a magnetized vector pattern to a spatial lighting modulator which is formed from a magneto-optical material; and a step of inputting linearly polarized light into the spatial lighting modulator and playing an image according to the digitized hologram pattern.

The present disclosure relates to a holographic reproducing apparatus comprising: a light source configured to supply a reproducing light beam to be incident to a photorefractive crystal, wherein the photorefractive crystal has holographic images recorded therein in a plurality of different angles respectively; a reflective mirror configured to reflect the reproducing light beam emitted from the light source to the photorefractive crystal; and a driving mechanism connected to the reflective mirror and configured to drive the reflective mirror to move on a plane elliptical arc, the plane elliptical arc is defined by using the light source and the photorefractive crystal as two mathematical focuses and using a predetermined constant, so that an incident angle of the reproducing light beam to be incident to the photorefractive crystal varies to form a plurality of reproducing light beams in different angles to be incident to the photorefractive crystal in sequence.

An optical detection system uses high-resolution holographic filters for target detection within a very-large field of view image acquired with a reflector. The holographic filter acts as an optical computer, mixing phase and amplitude information of known targets with light from the scene, automatically enhancing portions of the image that match threat objects or other object of interest. A lens forming a Fourier transform of the entire scene is used, and within that transform, the holographic information of a target or multiple targets is added. By acting as an inverse optical transfer function, the hologram gathers the target information to single point, and removes non-target background. Amplification is done by using a laser-illuminated hologram to create a phase-amplitude filter in a photorefractive material at the transform plane. By mixing the hologram and the scene at the transform plane, the matching is enhanced regardless of target location in the scene.