Patent classifications
G03H2223/22
Self-interference digital holographic system
A self-interference digital holographic system obtains interference patterns of incident light using a simple geometric phase lens, and obtains a holographic image of a target object using the interference patterns. The self-interference digital holographic is fabricated simply in a low cost and in a miniaturized size, and the use thereof as actual products is extended to a wide range of applications. The phase of incident light is be changed by rotating a polarizer, independently of a change in the optical path. Phase-shifting effects are obtained with fewer errors in all wavelength ranges, and a more accurate holographic image is produced. A single birefringence hologram is obtained by a one-time image-capturing process by simultaneously forming interference patterns from phase-shifted linearly-polarized beams by space division, using a phase shifter on the basis of space division. Moving holographic images can be captured.
Techniques for complex wavefront modulation
Various embodiments set forth optical patterning systems. Each pixel of the optical patterning systems includes an amplitude-modulating cell that is in line with a phase-modulating cell. The amplitude-modulating cell includes a liquid crystal and a drive method for modulating at least the amplitude of a wavefront of light that passes through the amplitude-modulating cell. The phase-modulating cell includes a liquid crystal and a drive method for modulating at least the phase of a wavefront of light that passes through the phase-modulating cell. In some embodiments, the amplitude-modulating cell shares a common ground with the phase-modulating cell. The amplitude-modulating cell and the phase-modulating cell can be used to independently control the amplitude change and phase delay imparted by the pixel, enabling complex wavefront modulation.
HOLOGRAPHIC VIRTUAL REALITY DISPLAY
Virtual reality (VR) displays are computer displays that present images or video in a manner that simulates a real experience for the viewer. In many cases, VR displays are implemented as head-mounted displays (HMDs) which provide a display in the line of sight of the user. Because current HMDs are composed of a display panel and magnifying lens with a gap therebetween, proper functioning of the HMDs limits their design to a box-like form factor, thereby negatively impacting both comfort and aesthetics. The present disclosure provides a different configuration for a virtual reality display which allows for improved comfort and aesthetics, including specifically at least one coherent light source, at least one holographic waveguide coupled to the at least one coherent light source to receive light therefrom, and at least one spatial light modulator coupled to the at least one holographic waveguide to modulate the light.
HOLOGRAPHIC CAMERA SYSTEM
A holographic camera system includes an imaging lens, a polarizer configured to circularly polarize light incident from the imaging lens, a geometric phase lens with a phase delay of λ/4, and an image sensor configured to replicate an interference pattern through self-interference of light output from the geometric phase.
Beam divergence and various collimators for holographic or stereoscopic displays
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 realising 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.
TUNABLE LIQUID CRYSTAL GRATING-BASED HOLOGRAPHIC TRUE 3D DISPLAY SYSTEM AND METHOD
A tunable-liquid-crystal-grating-based holographic true 3D display system comprises a laser, a filter, a beam expander, a semi-transparent semi-reflective mirror, a spatial light modulator, a lens I, a diaphragm, a tunable liquid crystal grating, a polaroid, a signal controller, a lens II and a receiving screen. The laser, the filter and the beam expander are used for generating collimated incident light. The spatial light modulator is loaded with a hologram of a 3D object. The diaphragm is positioned behind the lens I for eliminating a high-order diffracted light in the holographic true 3D display. The tunable liquid crystal grating is located on the back focal plane of the lens I and on the front focal plane of the lens II, and the signal controller is used for synchronously controlling the voltage of the tunable liquid crystal grating and the generation and loading of the hologram.
TECHNIQUES FOR COMPLEX WAVEFRONT MODULATION
Various embodiments set forth optical patterning systems. Each pixel of the optical patterning systems includes an amplitude-modulating cell that is in line with a phase-modulating cell. The amplitude-modulating cell includes a liquid crystal and a drive method for modulating at least the amplitude of a wavefront of light that passes through the amplitude-modulating cell. The phase-modulating cell includes a liquid crystal and a drive method for modulating at least the phase of a wavefront of light that passes through the phase-modulating cell. In some embodiments, the amplitude-modulating cell shares a common ground with the phase-modulating cell. The amplitude-modulating cell and the phase-modulating cell can be used to independently control the amplitude change and phase delay imparted by the pixel, enabling complex wavefront modulation.
Displaying three-dimensional objects
Methods, apparatus, devices, and systems for displaying three-dimensional objects by individually diffracting different colors of light are provided. In one aspect, an optically diffractive device includes: first and second diffractive components and a color-selective polarizer therebetween. The first diffractive component is configured to diffract a first color of light in a first polarization state incident at a first incident angle with a first diffraction efficiency at a first diffracted angle, and diffract a second color of light in a second polarization state with a diffraction efficiency substantially less than the first diffraction efficiency. The color-selective polarizer is configured to rotate the second polarization state of the second color of light to the first polarization state. The second diffractive component is configured to diffract the second color of light in the first polarization state with a second diffraction efficiency at a second diffracted angle substantially identical to the first diffracted angle.
Displaying three-dimensional objects
Methods, apparatus, devices, and systems for displaying three-dimensional objects by individually diffracting different colors of light are provided. In one aspect, a system includes a display having a plurality of display elements and an optical device including at least two beam expanders configured to expand an input light beam in at least two dimensions to generate an output light beam to the display by diffracting the input light beam to adjust a beam size of the input light beam in the at least two dimensions, the input light beam including a plurality of different colors of light.
APPARATUS FOR GENERATING HOLOGRAM AND A METHOD FOR GENERATING HOLOGRAM USING THE SAME
Disclosed herein an apparatus for generating hologram and a method for generating hologram using the same. The apparatus includes: a geometric phase modulator disposed to enable incident light from a target object to pass through and configured to modulate the incident light to a plurality of circular polarizations; an image sensor configured to receive the plurality of circular polarizations and to acquire an interference fringe generated by the plurality of circular polarizations as an image; and a polarization selective element equipped with a liquid crystal element, which controls an output polarization angle of the incident light according to an output polarization signal, and configured to sequentially output the incident light at output polarization angles different from each other.