Osa calculation for computer generated hologram using ray. Nobel prize winner dennis gabor, holographys inventor, saw the film after it was made and said it was the. In all these cases, a mechanically generated scratch hologram was obtained. This film examines the process of holography, types of holograms, and the uses of the hologram for artistic and scientific purposes, as demonstrated by tung h. This laser light strikes the hologram at the same angle that the reference beam struck the film during the exposure 2a. Unlike ordinary photographs, holograms record both phase and amplitude information. These computergenerated holograms or cghs are mappings of the complex amplitude magnitude and phase of light re. Unlike a photograph, which records the square of the electric eld, a hologram contains both the amplitude and phase information from the image. Digital holography optically generates a hologram, which is then recorded on a ccd camera, and an image is reconstructed using digital techniques. Algorithmic computer music contains 8 systems of music, 9 chapters with source code fi. Even if linked from, this file is not an official, binding release of the iypt, and should under no. Acknowledgment the author of this paper would like to thank professor cardinal warde for providing the laboratory facilities for this experiment. Clear, crisp, bright image with computer generated hologram cgh.
Applications of computergenerated holograms for interferometric measurement of large aspheric optics j. Relationship between image size i and field of view fov in true 3d floating image generation. The wavefront on the cgh plane is calculated by wavefront propagation simulation from rs plane. For an integral hologram we use a series of images of an object either rotating or being moved laterally along the horizontal axis. Department of precision mechanical engineering, shanghai. Computergenerated hologram cgh 1 includes a unique capability for recording and reconstructing the desirable amplitude and phase of object light, leading to a wide use of this technique in optical applications such as threedimensional 3d displays 2, projections 3. Back then, the holograms were calculated using a very imposing hp minicomputer.
Clear plastic sheet, scissors or stylus and tape or glue. Burge steward observatory mirrorlab, university of arizona tucson, arizona 85721 abstract interferometric optical testing using computer generated holograms cghs has proven to give highly accurate measurements of aspheric surfaces. Mar 24, 2014 this feature is not available right now. In optical holography, a wave front diffracted by the object propagates to the hologram plane, where it interferes. Computergenerated holograms from the invention of the. No, each broken piece would let you see the image from its own unique perspective. Applications of computer generated holograms for interferometric measurement of large aspheric optics j. Generation and replication of computer generated hologram. For example, through a small hologram, a fullsize room with people in it can be seen as if the hologram were a window.
Because the invention of coherent light source laser 1964, holography was able to be realized. When you get a nicely focussed spot on the viewing screen, your instructor will give you a hologram to view. Computer generated holography as a threedimensional. Computer generated holograms have bean made practical by te introduction of fast fourier transform alogrithms the following discussion will brief the reader on the theory and concepts of optical holograms, the computer hologram, and the analogies or the computer hologram to its optical counterpart.
Computergenerated holography is a powerful technology suitable for a wide range of display types, including 2d, stereoscopic, autostereoscopic, volumetric, and true 3d imaging. I fx is a bandlimited function, it can be recovered from f s x by passing f, x through a low pass filter. It represents influence of all technological steps into quality of the final product. Computational highlight holography acm siggraph asia. After the lap was removed and the surface was cleaned, two clear ghost images of theabsent lap were visible in full detail, in each of four abrasion test areas. The reason that they use lasers instead of regular white light is because laser light is coherent. Because phase is a relative property, construction of a. For example, cgh is used to make holographic optical elements. The main steps in the simulation algorithm are discussed below. The techniques and principles of holography have been modi.
If a master optical system is not available for making a hologram, a synthetic or a computergenerated hologram cgh can be made to. Also initial picture, its hologram and reconstructed image are presented. Make your own holographic pyramid show holographic images on your phone or tablet easlily materials. Among our computer generated holography clients are nyu medical center, mitsubishi, the american museum of natural history, michigan state university and allied. The computer generated holograms were generated and reconstructed using matlab version r2012a. Basic principles and applications of holography spie. A hologram is an interference recording of a 3d surface. Hologravure as a computergenerated and laser engraved.
Algorithmic computer music contains 8 systems of music, 9 chapters with source code files in c, and mp3 examples in folders for each chapter. Pdf since its conception, holography has been put to a variety of uses including data storage, security, and interferometry. Gabor in 1948, it initially aimed at solving the resolution problem of electron microscope with coaxial holography in line hologram. Make your own holographic pyramid show holographic images on. Rs plane is set at near the object and the lightrays emitted by the object are sampled at the plane. This is also true for the computer generated holographic images. Computer generated holography appears to be another promising process to provide true three. Fourier optics and computer generated hologram 5 in matlab, even if the size of the object is not exactly n x n it can be used for manipulation using image resize tools interpolation techniques. Computer generated hologram cgh 1 includes a unique capability for recording and reconstructing the desirable amplitude and phase of object light, leading to a wide use of this technique in optical applications such as threedimensional 3d displays 2, projections 3. To view the hologram, illuminate from the front and move the film around to observe the reconstructed image. Understand that there are two basic types of hologramstransmission and. Then the use of more sophisticated devices capable of recording computer generated grey scale images was suggested for recording computer generated holograms and computer generated holograms that can reconstruction good quality grey scale images were produced 3,4.
This tiff file then will be printed on film at high resolution. Use of computer generated holograms for alignment of complex null correctors rene zehnder, james h. Fullcolor computergenerated hologram i the double parabolic projection system is composed of double parabolic mirrors. Osa calculation for computer generated hologram using. Computer generated holograms cgh provide a more flexible process. In a binocular view these ghost images were plainly situated above and below the actual optical surface, an appearance. Computer generated hologram cgh has an important advantage 5. A computergenerated hologram will be stored in a tiff format file.
The application of computer generated holograms to the interferometric testing of aspheric optical elements has been investigated, and it has been shown that they provide a convenient and practical method of producing an aspheric reference wavefront. Index terms computer generated hologram cgh, fourier transformation, gerchbergsaxton algorithm. A diagram of the cnn hologram serrao, 2008 musion system company seamlessly integrated their 3d holographic display technology with ciscos telepresences system to create the worlds first. What that means is that all of the light waves in a laser beam are the same size, and vibrate at exactly the same time. Contact us for details on the hologram transfer process. Computational highlight holography acm siggraph asia 2010. In other words, optical holography is the forefather of digital. The two places on campus that can provide us with such equipment are the interactive multimedia lab iml and audio video av. Burge and chunyu zhao college of optical sciences, the university of arizona 1630 e. Achieving fast computergenerated hologram calculations.
As explained earlier the aim of this work is also the same, which is to devise a. These holograms are also known as volume holograms. Generated hologram floating on a dual parabolic projection system, chinese optics letters, august, 2015 a double parabolic mirror projection system. The reason that the reflection hologram can be viewed under white light is that the bragg planes are spaced in such a. Computergenerated holography as a generic display technology. In a binocular view these ghost images were plainly situated above and below the actual optical surface, an appearance commonly associated with a reflection hologram. The mechanic of the holographic printer moves the holographic film plate or the.
Creating a reflection hologram of a magnified object. Because cghs can control all aspects of the optical wave, threedimensional imagery can be presented to an audience. Holographys unique ability to generate accurately both the amplitude and phase of light waves enables applications beyond those limited by. A theory is offered to explain the phenomenon by simple geometry. Holographic threedimensional imaging of terracotta. Luminit computer generated holograms allow viewers to see clear, crisp, and bright holographic images without the need of glasses or other special eyewear. The fullcolor computergenerated hologram is a real image, which could. Holographic interferometry encompasses an entire discipline in mechanical.
Computergenerated holograms cghs are diffractiveoptical elements that offer the possibility of creating waveoptical display systems that are under complete computer control. Use of computer generated holograms for alignment of. All programs are procedurally generated, new music each time executed, and saved to a general midi file on the computer. After the lap was removed and the surface was cleaned, two clear ghost images of the absent lap were visible in full detail, in each of four abrasion test areas.
Upon the proper recording, reconstruction, and viewing conditions, unlike the traditional 2d photography, the image appears to be 3d again. The surface consists of small grooves with patches of paraboloids or hyperboloids, each of which produces a highlight when illuminated by a directional light. Burge steward observatory mirrorlab, university of arizona tucson, arizona 85721 abstract interferometric optical testing using computergenerated holograms cghs has proven to give highly accurate measurements of aspheric surfaces. Fold it on the dotted lines you can mark it with a pen if needed. A visually striking image phenomenon has been noticed during mechanical abrasion of a plane nickeloptical surface.
Holography 1 background the word hologram was coined from the greek word \holos which means whole, because the recorded hologram contains all the information of the image eld. Normally you can only point out things in a 2d image, but with a. A diagram of the cnn hologram serrao, 2008 musion system company seamlessly integrated their 3d holographic display technology with ciscos telepresences system to create the worlds first real time virtual presentation musion system, 2009. A visually striking image phenomenon has been noticed during mechanical abrasion of a plane nickel optical surface. Pdf holography is the science of making holograms which are usually intended for displaying three dimensional images. Hologram modeled at the origin of a lefthand coordinate system 316. Because theyre all the same size, all of the waves will bend the same way. Pdf since its conception, holography has been put to a variety of uses.
Computer generated holography is a powerful technology suitable for a wide range of display types, including 2d, stereoscopic, autostereoscopic, volumetric, and true 3d imaging. Gardner illustrate the physical principle of the mechanically produced preliminary stage of holography in the article a mechanically generated hologram. Anywhere you look through a window you see whats on the other side. This computergenerated holography cgh has become a subbranch that is growing rapidly. Clear, crisp, bright image with computer generated. Then the lightrays are transformed into the wavefront with using the fourier transforms. Computer generated holography cgh is the method of digitally generating holographic interference patterns. To understand the process of image reconstruction by producing simple holograms on a laser printer and reading them out with an optical lens system. With luminit threedimensional computer generated holography, a predetermined image e. Errors in this technique are due to aberrations in the electron optics, beam drift, instabilities in the controlling electronics, and positioning of the stepper. The idea of specular holography predates wavefront holography by many years. If this hologram is broken into small pieces to be less wasteful, the hologram can be covered by a piece of paper with a hole in it, one can still see the entire scene through each piece. The wavefronts that would emerge from the objects are reconstructed by the propagation of light through the hologram.
Computer generated holography and digital holography were built on the principles of optical holography. The technology for fabricating computergenerated holograms is demanding and requires advanced lithographic techniques. Computergenerated holography avoids the interferometric recording. Computergenerated holography cgh is the method of digitally generating holographic interference patterns. Computational highlight holography converts threedimensional computer models into mechanical holograms fabricated on specular reflective or refractive materials. For hologravure, a computer program generates the hologram and a laser is used for engraving it. Jan 22, 2016 computer generated holography cgh is the method of digitally generating holographic interference patterns. If a hologram breaks is the whole image visible in each piece. Carefully adjust your lenses to get the sharpest image. Techniques and applications iii, 5 2 parameter e is a small delay in the positions of the sampling pulses with f respect to the origin of the function fx. Among our computer generated holography clients are nyu. The main steps to follow in the development of a computer generated hologram and the reconstruction of the object from the hologram is shown in the figure 1. Essentially, the hologram is illuminated with light of the same wavelength that was used to make it. For every picture containing on the lcd, a hologram should be produced.
Optical damage as a computer generated hologram recording. When i was appointed in 1992 to teach these practicals at the institute, i soon found that this experiment was an endless source of fascination for our engineering students. It would be interesting to be able to do so, since you could then easily show large things without having to bring them along. Holography 1 holography introduction and background the aesthetic appeal and commercial usefulness of holography are both related to the ability of a hologram to store a threedimensional image. University blvd, tucson, az 85721 abstract large diameter, nonaxisymmetric aspheric mirrors can be measured interferometrically using null correctors that. Achieving fast computergenerated hologram calculations 1289 respectively, k is the wave number of the reference wave defined as 2. A computer generated hologram or a cgh is a computed interference pattern of such 3d scene. Preparation to the young physicists tournaments 2014. Pdf computergenerated holography as a generic display. Unlike these mentioned works, a hologravure is not mechanically generated. Typical ebeam recorders will write a 1mm area with a resolution of 0. The making of a computergenerated hologram features. We introduce a new algorithm for calculating computer generated hologram cgh using raysampling rs plane.
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