A method of computing a hologram by determining the wavefronts at the approximate observer eye position that would be generated by a real version of an object to be reconstructed. In normal computer generated holograms, one determines the wavefronts needed to reconstruct an object; this is not done directly in the present invention. Instead, one determines the wavefronts at an observer window that would be generated by a real object located at the same position of the reconstructed object. One can then back-transforms these wavefronts to the hologram to determine how the hologram needs to be encoded to generate these wavefronts. A suitably encoded hologram can then generate a reconstruction of the three-dimensional scene that can be observed by placing one's eyes at the plane of the observer window and looking through the observer window.

A spatial light modulator and a method for displaying a computer generated hologram are disclosed. The spatial light modulator includes a plurality of MEMS units arranged in an array, each of the MEMS units corresponds to a pixel of a computer generated hologram and includes a sensing device, a light shielding portion and a driving device. The sensing device is configured for receiving position information that is obtained through Roman encoding a pixel corresponding to an MEMS unit including the sensing device and the position information is transmitted to the driving device by the sensing device. The driving device is configured for controlling the light shielding portion to move to a position corresponding to the position information in response to the received position information of the light shielding portion when the present frame is displayed.

A method for integrating a synthetic hologram in an image of a scene, including: forming, from a first image of the scene, a first matrix including pixels of two shades according to the gray level of the corresponding pixel of the first image, and a second matrix, image of the gray level difference between the corresponding pixels of the first image and of the first matrix; forming a third matrix based on a second image; forming a fourth matrix having each pixel including a central area with a surface area determined by the corresponding element of the second matrix and off-centered in the pixel according to the corresponding pixel of the third matrix; and performing a lithography of an opaque layer at the surface of a plate according to the pattern defined by the fourth pixel matrix.

There is provided a pixel transform method for JPEG/MPEG compression of double phase-amplitude coded holograms. According to an embodiment, a hologram compression method transforms a hologram represented by a complex number into a hologram represented only by a phase, rearranges pixels of the transformed hologram, and compresses the rearranged hologram. Pixels of a DPAC hologram are rearranged before the DPAC hologram is compressed in a standardized image/video compression technique, so that a high frequency component is prevented from occurring when a hologram is compressed. Accordingly, hologram quality degradation occurring when a DPAC hologram is used in a standardized image/video compression technique can be prevented.