Now that ultrashort laser pulses can be used in holography, the temporal and spatial resolution approach the same order of magnitude. In that case the limited speed of light sometimes causes large measuring errors if correction methods are not introduced. Therefore, we want to revive the Minkowski diagram, which was invented in 1908 to visualize relativistic relations between time and space. We show how this diagram in a modified form can be used to derive both the static holodiagram, used for conventional holography, including ultrahigh-speed recor- dings of wavefronts, and a dynamic holodiagram used for studying the apparent distortions of objects recorded at relativistic speeds. The modified holodiagram is used to solve and visualize in a graphical way a number of problems that are important for the evaluation of ultrahigh-speed recor- dings. A simplified diagram is introduced to explain the focusing effect of fast- moving light sources or observers. The diagram is used to show the distortion of an orthogonal coordinated system to simplify the study of apparent deformations of arbitrary shaped rigid objects. These distortions are compared with those of pulse fronts or wave fronts of light observed with light-in-flight recordings.
Quantum mechanical measurement involves an irreversible loss of information, sometimes called the collapse of the wavefunction. We show that with a number of such irreversible acts we can achieve reversibility Ã¢â‚¬â€ wavefunction reconstruction. The reconstructed wavefunction is equivalent to the original in terms of its capability of predicting measurements.
Holophony is in acoustics what holography is in optics. Just as might claim to be the ideal optical illusion, so might claim to be the perfect auditory illusion. As illustration of general principles theoretical basis was obtained by the Bourbakt group, and otherwise by Gabor theory. It is shown that using limited number of secondary Huygens sources one can provide a very presentable auditory illusion imaging the primary sound source.
Holograms play a number of unique and essential roles in optical computing. We enumerate those roles. We then defend the following proposition. Anything that can be done holographically can be done nonholographically, but not as well. Thus, holography is always the method of choice for complex optical tasks.
The development of faster and more efficient computers in recent years has been driven by a seemingly unending thirst for communication, interaction, automation, control issues, information availability, and a yearning for new understanding of the self-organization principles of ourselves and our envi- ronment. The challenges of the future force to create and study new concepts of adaptive information processing and to implement for faster communication novel computer architectures based on fundamental quantum theoretical principles.
The advent of low-loss optical fibers in the early 1970s was a major event in the field of communications. Since then, material and fabrication technologies have progressed rapidly and, non-communications applications for fiber optics have become widespread. For example, optical-fiber components are routinely used in holography and holo-interferometry to realize significant improvements in stability, flexibility and accessibility. This paper reviews the history of the application of individual single- and multimode fiber-optic components to the manipulation of both object and reference beams, and the use of multimode fiber-optic image bundles for object-to-hologram wavefront transmission. The advantages and disadvantages of singlemode versus multimode fiber-optic components will be discussed, and techniques for improving the stability of multimode fiber-optic components will be presented. Tests conducted using singlemode fibers (SMF) as stable illuminators and a singlemode image transmitting (SIT) fiber-optic component for wavefront transmission between the object and the hologram will be described. Other techniques which rely on holographic/fiber optic recordings, such as radial metrology and real time moire interferometry, will also be discussed.
Investigations of transparent objects like stationary plasmas on the basis of hologra- phic interferometry are difficult because of the relatively small fringe shift caused by these phase objects. For tomographic reconstruction procedures the phase shifts derived from the interferograms have to be particularly accurate , otherwise the reconstruction of the refrac- tive index distribution of the inhomogeneous plasmas is not reliable. The highly resolved phase profiles can be obtained by the use of spatial heterodyning, providing an accuracy of 2n/20 in the determination of the phase. A test of the optical arrangement and the computer-tomographic reconstruction algorithms is performed. The method is applied to diagnostics of different plasmas, such as high frequency plasmas and dc-glow-discharges. A special feature of these investigations is the use of resonance interferometry, in order to determine spatial distributions of particle densities of certain atoms in distinct states.
The difference holographic interferometry (DHI) may be used for direct optical compa- rision of two nominally identical objects (master and test) and to display the re- sults of the comparision in form of interference pattern related to the difference in deformation, shape or refractive index change of the two objects. After a general discussion of concepts the main techniques of the DHI will be intro- duced, and typical applications presented.
The history of Soviet holography is dominated by the invention of the reflecting hologram by Yuri Dcnisyuk, the development of ultra-fine grain recording materials by the work of Kirillov and the evolution of colloidal processing techniques under Usanov. The colloidal images so created are of very low noise and high definition and were a shock to Western scientists at the Holography meeting in Ulyanovsk in 1979. The general approach to making silver halide reflection holograms in the West is to use staining pyrogallol developers and bleaches which involve physical transfer of halide to create the modulation. This paper deals with a previously unpublished process for the silver halides created by the author in 1979 which bridges the gap between the Soviet and Western methods.
In this paper, fundamentals of hologram interferometry are discussed, procedures for recording and recon- struction of holograms are presented, methods for quantitative interpretation of holographic data are outlined, and representative systems for automated holographic analysis are described. In these discussions, emphasis is placed on quantitative analysis of holographic data. Selected applications are illustrated with representative examples.
Reduction of the information content of a hologram to the minimum necessary to support strong spatial perception makes possible the interactive computation, transmission, and display of three-dimensional animated holographic images.
The analysis of possible applications of the modern science achievements in various spheres of culture is one of the important and rather actual prob- lems of the present. In this respect optical holography, as a new method of recording and reconstruction of light fields, affords extraordinary potentia- lities to be applied in the domain of culture, viz, in art and museology, un- common to optics and quantum electronics. These possibilities are analyzed in the presented paper. It is also connected with the idea to show for the museo- logists, who are not very much acquainted with this new field, the real achie- vements in holography, different aspects of their applications in the museum life and to discuss these possibilities by the rather simple way.
In this paper the steps necessary for plate making and processing for dichromated gelatin holography will be discussed.. This article will refer to work of other people as well as work done in my own laboratory. When dichromated gelatin is used as a recording-medium special effects will occur. These effects are not, or not in the same extension, present when other recording-media are used. Mostly these effects are caused by the difference in which the recording is stored in the photo-sensitive layer. Whereas, in the case of silverhalide, the change of refractive-index of the silver-molecules embedded in gelatin is used, in the case of dichromated gelatin the change of retractive- index of the gelatin itself is used. This difference has a major influence on parameters such as efficiency, spectral replay response and resolution.
Holograms can be synthesized from a series of photographic images, and such holograms are convenient for displaying 3D images even if conventional holograms are difficult or impossible to record. Three kinds of synthesized holograms, multiple-exposure holograms, cylindrical holographic stereograms and conical holographic stereograms, are described for the purpose of medical and industrial 3D display.
Although today endoscopy has established its place in medical diagnostics, it has not yet exceeded the function of a qualitative, subjective observation method. Combination of coherent metrology, especially holographic interferometry, with endoscopy opens the possibility for high-resolving, non-contactive, non-destruc- tive intra-cavity measurements. In addition, modern developments in micro-optics provide essential miniaturization of endoscopic devices. The introduction of micro-optics into holographic endoscopy raises problems due to limitations in op- tical signal-to-noise ratio (SNR) caused by small apertures of the image transmit- ting systems as well as due to restrictions of common holographic recording mater- ials for in-situ recording and reconstruction with fast-repetition rate and high (line) resolution. Three developments in micro-optics can help to overcome these obstacles and give main impulses to actual progress in holographic endoscopy: - micro-optical gradient-index imaging systems, - micro-optical (single-mode) imaging fiber bundles, and - electro-optical crystals as holographic storage devices.
A presentation of a recording technique for making pulse laser hologram portraits is given. The master recording studio is described as well as the transfer setup used for making reflection copies of pulse masters. A list of references of published papers concerning the art and the technique of making holographic pulse portraits in general, is provided.
It is altogether fitting that in this commemorative conference, we celebrate the one application of holography that would have pleased Dennis Gabor the most, its contribution to culture and education. Among the many uses of holography, the most frequently lauded are display, interferometry, HOE, and a myriad of other technical applications. Seldom mentioned is its important contribution to culture and education, the theme of this conference. Herein we wish to argue this case, and detail the steps we have taken to implement it to a broad spectrum of the U. S. public over the last twenty years. With the consolidated effort of colleagues around the world, we expect the subject of holography to become an integral part of basic education, starting from elementary school.
The project "Herbarium Holographicum" in fact started from a holographic reaction of frustration, evoluated quite rapidly to a passionate search of "hologeny" of vegetal objects on one side, but also led to the search of symbolic significance of vegetals, to a trial to multiplicate holographically a historical collection of microscopic plant sections, to some efforts of demystification of holography by integrating pieces of Herbarium Holographicum in "normal everyday" objects, and finally to a project of a monumental piece of multimedia art that, when the sponsors are found, will become one of the largest holograms of the world.
One of the most successful applications of Holography,in recent years,has been its use as an optical security technique.Indeed the general public's awareness of holograms has been greatly enhanced by the incorporation of holographic elements into the VISA and MASTERCHARGE credit cards.Optical techniques related to Holography,are also being used to protect the currencies of several countries against the counterfeiter. The mass production of high quality holographic images is by no means a trivial task as a considerable degree of expertise is required together with an optical laboratory and embossing machinery.This paper will present an overview of the principal holographic and related optical techniques used for security purposes.Worldwide, over thirty companies are involved in the production of security elements utilising holographic and related optical technologies.Counterfeiting of many products is a major criminal activity with severe consequences not only for the manufacturer but for the public in general as defective automobile parts,aircraft components,and pharmaceutical products, to cite only a few of the more prominent examples,have at one time or another been illegally copied.
Answers are looked for questions such as: How far has acoustical holography a future, can it beat the wavelength resolution limit, what is shadow-casting and dark field reconstruction holography, can holograms be recorded with incoherent white light or in the single photon region, how about cosmic holography, bioholography and holographic ontology, and last but not least, who is a "homo ludens holographicus"?
What follows are anecdotes and remarks offered to me on the person of Dennis Gabor by participants of this conference. They reveal the human and intellectual sides of him not found in his formal publications. These notes are quoted verbatim.