A holographic display apparatus includes: a light source; a spatial light modulator configured to modulate light from the light source according to an image to be displayed on an object plane; and a processor configured to generate a computer generated hologram (CGH) in which a phase value of hologram data to be displayed on a reference plane of the spatial light modulator is 0, the processor being configured to apply a light modulation signal based on the CGH to the spatial light modulator.

Disclosed are an active complex spatial light modulation method and apparatus for an ultra-low noise holographic display. The active complex spatial light modulation apparatus includes a substrate and a petal antenna including three petal patterns arranged on the substrate, dividing a complex plane into three phase sections, and modulating the input light into three-phase amplitude values corresponding to the phase sections. The petal antenna may have a point symmetry shape based on the center point of the petal antenna.

The invention discloses an optical system for generating arbitrary-order optical vortex arrays and finite optical lattices with defects, comprising a laser, a collimating and beam-expanding system, a spatial light modulator, a 4-f lens system, and an image detector which are disposed according to a light path. After passing through the collimating and beam-expanding system, the linearly-polarized Gaussian beam emitted by the laser is radiated to the spatial light modulator to be modulated in complex amplitude; the first-order diffraction beam of the emergent light generates an arbitrary-order alternating optical vortex array on the back focal plane of the first 2-f lens system, and an adjustable finite optical lattice with defects on the back focal plane of the second 2-f lens system. The topological charge value of each vortex and the spacing between vortices, in the generated arbitrary-order alternating optical vortex array, can be precisely controlled.

A holographic display comprises: an illumination source which is at least partially coherent; a plurality of display elements positioned to receive light from the illumination source and spaced apart from each other, each display element comprising a group of at least two sub-elements; and a modulation system associated with each display element and configured to modulate at least a phase of each of the plurality of sub-elements.

A heads up display system with a variable focal plane includes a projection device to generate light representative of at least one virtual graphic, an imaging matrix to project the light representative of the at least one virtual graphic on at least one image plane, a display device to display the at least one virtual graphic on the at least one image plane, and a translation device to dynamically change a position of the imaging matrix relative to the display device based, at least in part, on a predetermined operational parameter to dynamically vary a focal distance between the display device and the at least one image plane.

A method of calculating a hologram having an amplitude and a phase component. The method comprises (i) receiving an input image comprising a plurality of data values representing amplitude. The method then comprises (ii) assigning a random phase value to each data value of the plurality of data values to form a complex data set. The method then comprises (iii) performing an inverse Fourier transform of the complex data set. The method then comprises (iv) constraining each complex data value (X1, X2) of the transformed complex data set to one of a plurality of allowable complex data values (GL1-GL8), each comprising an amplitude modulation value and a phase modulation value, to form a hologram, wherein, the phase modulation values (GL1-GL7) of the plurality of allowable complex data values substantially span at least 3π/2 and at least one of the allowable complex data values has an amplitude modulation value of substantially zero (GL8) and a phase modulation value of substantially zero.

A three-dimensional light modulator, of which the pixels are combined to form modulation elements. Each modulation element can be coded with a preset discrete value such that three-dimensionally arranged object points can be holographically reconstructed. The light modulator is characterized in that assigned to the pixels of the modulator are beam splitters or beam combiners which, for each modulation element, combine the light wave parts modulated by the pixels by means of refraction or diffraction on the output side to form a common light beam which exits the modulation element in a set propagation direction.

A spatial light modulator (SLM) includes a first liquid crystal panel and a second liquid crystal panel that are oppositely configured, and a polarization adjustment part configured between the first liquid crystal panel and the second liquid crystal panel. An alignment direction of the first liquid crystal panel is parallel to an alignment direction of the second liquid crystal panel. The first liquid crystal panel is configured to perform a phase modulation on incident linear-polarized light. The polarization adjustment part is configured to rotate, by a preset angle, a polarization direction of linear-polarized light exited from the first liquid crystal panel. The second liquid crystal panel is configured to adjust a polarization state of linear-polarized light exited from the polarization adjustment part to adjust an amplitude of exited light.

Provided is a method of generating a computer-generated hologram (CGH), the method including obtaining complex data including amplitude data of object data and phase data of the object data corresponding to a spatial light modulator (SLM) plane by propagating the object data from an image plane to the SLM plane, encoding the complex data into encoded amplitude data, and generating a CGH based on the object data including the encoded amplitude data.

Provided is a method of generating a computer-generated hologram (CGH), the method including obtaining complex data including amplitude data of object data and phase data of the object data corresponding to a spatial light modulator (SLM) plane by propagating the object data from an image plane to the SLM plane, encoding the complex data into encoded amplitude data, and generating a CGH based on the object data including the encoded amplitude data.