Displaying real 3-D object images using a computer-generated hologram : a thesis presented in partial fulfillment of the requirements for the degree of Master of Science in Computer Science at Massey University

The magic of an optical hologram that produced by optical system offer us a never ending sense of wonderment. The images reconstructed from an optical hologram exhibit all of the three dimensional properties with full, rich perspective effects, enabling us to catch sight of an object behind another by mere tilt of the head. Computer-generated holograms, synthetic holograms and computer holograms are terms used to refer to a class of holograms that are produced as graphical output from a digital computer. It has been reported that a computer-generated hologram can also yield a three dimensional image. The main advantage of the computer-generated hologram is that it can be used to generate a three dimensional image of an object that may not physically exist. But can a computer-generated hologram be used as a three dimensional display device? This thesis examines the ability of a computer-generated hologram as a three dimensional display device. Many techniques have been used to produce computer-generated holograms. Mathematical descriptions of computer-generated holograms are discussed. The quality of the images reconstructed from these computer-generated holograms are examined. The computation time for producing these computer-generated holograms are compared

Reduction in the reconstruction error of computer-generated holograms by photorefractive volume holography

We suggest a method for coding high-resolution computer-generated volume holograms. It involves splitting the computer-generated hologram into multiple holograms, their individual recording as volume holograms by use of the maximal resolution available from the spatial light modulator, and subsequent simultaneous reconstruction. We demonstrate the recording and the reconstruction of a computer-generated volume hologram with a space-bandwidth product much higher than the limitation imposed by the interfacing spatial light modulator. Finally, we analyze the scheduling procedure of the multiple holographic recording process in photorefractive medium in this specific application

High-space bandwidth product computer-generated holography using volume holography

We suggest a method for coding high resolution computer-generated volume holograms. It involves splitting the computer-generated hologram into multiple holograms, each individually recorded as a volume hologram utilizing the maximal resolution available from the spatial light modulator. Our method enables their simultaneous subsequent reconstruction. We demonstrate the recording and the reconstruction of a computer-generated volume hologram with a space bandwidth product much higher than the maximal one of the spatial light modulator used as an interface. Finally, we analyze the scheduling procedure of the multiple holographic recording process in photorefractive medium in this specific application

Real-time computer-generated hologram by means of liquid-crystal television spatial light modulator

A novel use of liquid-crystal television (LCTV) is described. It is shown that, if the phase nonuniformity of the LCTV is corrected by a liquid gate, then a simple computer-generated hologram can be written and coherently reconstructed

Superpositions of the Orbital Angular Momentum for Applications in Quantum Experiments

Two different experimental techniques for preparation and analyzing superpositions of the Gaussian and Laguerre-Gassian modes are presented. This is done exploiting an interferometric method on the one hand and using computer generated holograms on the other hand. It is shown that by shifting the hologram with respect to an incoming Gaussian beam different superpositions of the Gaussian and the Laguerre-Gaussian beam can be produced. An analytical expression between the relative phase and the amplitudes of the modes and the displacement of the hologram is given. The application of such orbital angular momenta superpositions in quantum experiments such as quantum cryptography is discussed.Comment: 18 pages, 4 figures. to appear in Journal of Optics

Generation of Generalized-Gauss Laser Beams via a Spatial Light Modulator

Generalized-Gauss laser beams can be described as a continuous transition between the well-known Hermite-Gauss (HG) and Laguerre-Gauss (LG) laser beams. A spatial light modulator (SLM) was made by removing the liquid crystal display (LCD) from an overhead projector. The homemade SLM, encoded with a computer-generated hologram, was then used to convert a fundamental Gaussian beam from a small frame Helium-Neon (HeNe) laser into several different orders of Generalized-Gauss (GG) beams. The experimentally generated GG beam profiles matched the theoretically expected profiles

Multifacet holographic optical elements

New types of holographic optical elements, combining the flexibility of computer generated holograms with the large space bandwidth product and high diffraction efficiency of interferometrically recorded volume phase holograms, are demonstrated. The optical elements are recorded by subdividing a volume hologram film surface into numerous small areas (facets), each of which is individually exposed under computer control. Each facet is used to produce a portion of the desired final wavefront. Three different optical elements are demonstrated