A method for encoding a digital hologram represented by values associated respectively with pixels in a plane defining the digital hologram includes forming matrix blocks associated respectively with regions composed of contiguous pixels, each matrix block containing elements determined as a function of the values of the pixels in the region associated with the respective matrix block, applying to each of the matrix blocks a space-frequency transformation to obtain, for each matrix block, a set of coefficients respectively corresponding to different two-dimensional spatial frequencies within the respective matrix block, constructing two-dimensional structures each including coefficients from sets of coefficients and associated with two-dimensional spatial frequencies meeting a criterion that is dependent on the two-respective dimensional structure, and encoding the constructed two-dimensional structures.

A holographic image generation system including a spatial light modulator; a light source; a temporal modulator; a light sensor and a demodulator. The spatial light modulator has pixels. The light source illuminates the spatial light modulator. The temporal light modulator modulates an output intensity of the light source over time to encode holographic data representing a hologram. The light sensor is associated with a spatial light modulator and receives light from the light source and generates a signal representative of the output intensity of the light source. The demodulator is connected to the light sensor to receive the signal. The demodulator decodes the signal to obtain the holographic data. The demodulator is connected to the spatial light modulator to set the pixels of the spatial light modulator in accordance with the holographic data to display the hologram ready for illumination by the light source to form a holographic reconstruction.

A method of generating a hologram includes receiving three-dimensional (3D) image data, dividing 3D image data into data groups which are independent from one another, by a first processor; calculating, from at least one of the data groups, hologram values to be displayed at respective positions on a hologram plane, by the first processor; calculating, from at least another one of the data groups, hologram values to be displayed at the respective positions on the hologram plane by a second processor, and summing the calculated hologram values for each of the respective positions on the hologram plane, by the first processor or the second processor, or by the first processor and the second processor in parallel.

A light shuttering device comprises a plurality of liquid crystal cells, wherein each liquid crystal cell is operable in a first optical state or a second optical state in response to a respective first or second drive signal. A drive circuit comprises a plurality of switches and a drive controller. Each switch is arranged to output the respective first or second drive signal to a respective liquid crystal cell. The drive controller is arranged to sequentially update the output of each switch during an update cycle. The drive circuit is arranged to determine the order in which the switches are sequentially updated during an update cycle based on any changes to the respective drive signals that will be made during the update.

The holographic Christmas tree is a holographic device. The holographic Christmas tree projects a three-dimensional image of a Christmas tree. The holographic Christmas tree includes a pedestal, a holographic projector, a substrate, and an image. The image is the three-dimensional image of a Christmas tree. The holographic substrate projects the image into the substrate. The pedestal contains the holographic projector.

[Problem] Propagation of parallel light inside thin glass or plastic material had not been considered to be feasible because of difficulties in producing parallel light with large aspect ratio and in light-guiding it into thin material. For this reason, there had been a problem that holograms of edge-lit reproduction type were not being brought to practical use.

[Means for Solution] A compact, simple collimator optics has been successfully made by placing a holographic diffraction grating close to a diverging light source to propagate it at the critical angle inside the medium. By making an array of this diffraction grating it has become possible to propagate parallel light of any aspect ratio inside a thin plate. Hitherto unrealized image display devices and signal devices have become possible by using the holographic diffraction gratings as described in the foregoing, or other diffraction optical elements, to introduce light from a plurality of light sources, in combination with edge-lit reproduction type image holograms.

A method for manufacturing a light reflection member producing a hologram effect of an ornament, the method including the steps of: applying an adhesive to a substrate; attaching a background member to the adhesive; applying an adhesive to the background member; applying silibeads to the adhesive; heating the silibeads to a temperature of 1605 C.; applying an adhesive to the silibeads; applying polystyrene beads to the adhesive; and heating the polystyrene beads to a temperature of 1005 C. According to the present invention, the method for manufacturing the light reflection member for producing the hologram effect of the ornament can produce the hologram effect from the solid light behind the ornament through the illuminance of the lighting member and the reflected light from the light reflection member, thereby providing the dynamic hologram effect for the ornament.

There is provided a holographic image generation system comprising: a spatial light modulator (SLM) having pixels; a light source configured to illuminate the SLM; a temporal modulator; a light sensor associated with the SLM; and a demodulator. The temporal light modulator is arranged to modulate an output intensity of the light source over time to encode holographic data representing a hologram. The light sensor is configured to receive light from the light source and generate a signal representative of the output intensity of the light source. The demodulator is connected to the light sensor to receive the signal, and is arranged to decode the signal to obtain the holographic data. The demodulator is further connected to the SLM to set the pixels of the SLM in accordance with the holographic data to display the hologram ready for illumination by the light source to form a holographic reconstruction.

Methods and systems (terminals, devices) for the generation, the retrieval and the display of computer-generated holographic images through a head-mounted display. The holographic images may be used as virtual retrievable tags for display in augmented reality.

A holographic display system and an electronic device are provided. The holographic display system includes: at least a first optical module, a second optical module and a third optical module arranged sequentially in a first direction towards which the backlight is to be emitted. The first optical module is configured to transmit light of a first polarization direction, the second optical module is configured to transmit light of a second polarization direction, and the third optical module is configured to transmit light of a third polarization direction. The first polarization direction and the second polarization direction are at an angle of ?.sub.1, the second polarization direction and the third polarization direction are at an angle of ?.sub.2, and the first polarization direction and the third polarization direction are at an angle of ?.sub.3, ?.sub.3 is greater than at least one of ?.sub.1 and ?.sub.2.