A synthesis principle, implemented through holography, has been applied to microscopy at large space-bandwidth product. Indicatively, the method succeeds in doubling the aperture of a good microscope objective. The experimental test shows the feasibility of the method.
A high resolution all-holographic line scanner for use in diode laser printers has been developed. The scanner consists of only a holographic lens and disk for laser beam scanning and focusing. No other optics are necessary. The holographic lens performs two functions. The first is the uniform correction of the beam aberration over the entire scan line length at the desired wavelength of the diode laser. The second is the correction of the aberration caused by wavelength variation of the diode laser. We developed a holographic lens with these two functions, and devised an all-holographic line scanner with a beam spot size of less than 120 μm (1/e2), for a scan line length of 252 mm and a wavelength tolerance of +10 nm. This level of performance is well suited to 300 dpi printing applications.
Holographic scanners/deflectors have been used to replace common mirrors with very limited success. When an application requires more than a simple polygon or when two or three functions can be performed by a single holographic element then the holographic approach appears more attractive and historically has been more successful. This paper reveiws 3 special purpose device designs with emphasis on the hologram design considerations, fabrication details and performance.
Within the last few years, a relatively new development intended for temporal information transmission has suddenly become a standard part of holography. Fiber optics offers numerous advantages over conventional components, as reported by various authors1-8 Herein we wish to acquaint holographers with some background information as well as some new developments.
Stereographic principles have been usefully employed in the production of display holograms. This paper addresses some of the difficulties encountered in the engineering of stereographic video displays and some of the workable counter measures available to compensate for these difficulties. The impact of diffraction is given particular attention in the discussion. Trade-offs between optimization for any one depth clue, such as accommodation depth clue, and general display performance are explored. Three related optical system geometries are discussed. These optical system geometries and some of their useful variations are diagrammed. Means for approximating important parameters such as; display brightness, viewing zone size, image resolution, and number of object scene views required are given. Methods of optimizing the important parameters to improve display performance and reduce its cost are included. Example solutions of the approximations are illustrated and compared to typical values that were experimentally measured.
Currently, space image data of the earth's surface is being primarily used with emphasis on two-dimensional information content. Three-dimensional image data acquisition is now emerging through the multi-lateral viewing capability of new spaceborne Visible/Infrared, and Synthetic Aperture Radar (SAR) Systems. Using a multiplicity of digitally produced, varying incidence angle views, we have produced holographic stereograms, viewable in white light, from Landsat, SIR-B and airborne SAR data.
The use of holographic optical elements with laser diodes and/or diode arrays for spacecraft communications is considered. Laser diodes are uniquely suited to spacecraft communications due to their low mass, compact size and high efficiencies compared to other candidate optical transmitters. However, the beamfront from these devices suffer aberrations and astigmatism (Fig. 1). Corrections to the beamfront for satellite communications typically require conventional optical solutions which employ multielement configurations. These solutions are quite massive and bulky and in some instances, can contribute significantly to the overall satellite payload.
The earliest reference to holographic applications appeared in the dental literature in 1972 when Wictorin, Bjelkhagen and Abramson described a method to study elastic deformation of defective gold solder joints in simulated fixed bridges. Their paper, published in the Swedish dental literature, offered a concise presentation of the interferometry technique which led to the development of other research applications of holographic interferometry(holometry) in dentistry. In this presentation, the development and application of the interferometry technique in the dental field will be discussed. Various interesting and potentially useful applications of holography have appeared in the dental literature over the past decade. Some of these, which will be discussed, include the use of holograms as a storage medium for dental study models, multiplexing of computer(CT) scan sections to form white light viewable holograms and the potential application of holographic training aids in the teaching of the basic courses of dental anatomy and restorative dentistry. In addition, some unique related applications will be mentioned including a laser reflection method for accurate non-contact measurement of tooth mobility/movement and a technique for contour mapping of occlusal surfaces to measure wear of restorative materials.
Knowing the fundamental or ultimate limits enables holographers to avoid attempting impossible tasks while pushing close to the optimum. We offer here some preliminary observations on diffraction limits, throughput limits, and brightness limits. We then offer two new theorems on angular and spectral resolution.
1986 was an extremely important and successful year for holography within Ilford Limited and for the development of silver halide holography as a whole. It is thus timely to summarise some of the major achievements of that year in respect of the progress made both in marketing and technological terms. In many respects the lessons learned by Ilford in its efforts to widen the markets for silver halide based holography are cf interest to smaller companies whose endeavours follow along similar lines.
Optical and microstructural properties of reflection holograms recorded in DMP-128 are reported. The optical properties are determined from transmission spectra of the holograms by ignoring the relatively small effects of light scattering and absorption. Microstructure is revealed by light and electron microscopic examination of hologram sections prepared either by diamond grit abrasion or by freeze fracture. Fringe planes are clearly seen with both sectioning procedures. The spacing between adjacent planes is strongly affected by processing conditions. Standard processing produces reflection holograms with fringe plane spacing that decreases continuously from the film:substrate interface to the film:air interface. These holograms have wide spectral bandwidths (100-200nm) and irregular band shapes. Narrow bandwidth holograms are produced from slightly more complicated processing steps. The optical properties of both types of holograms are compared to a theoretical model developed to account for nonuniform fringe plane spacing. Important experimental features such as spectral bandwidth and diffraction efficiency are readily explained by the theory and the observed microstructure.
The paper discusses actual knowledge and problems of the behaviour of real holographic recording materials with a gelatine host, especially silver halide emulsions. The properties of materials are studied on reflection diffraction gratings, where diffraction efficiency, optical noise. spectral or angular selectivity, transfer linearity of image modulation, e.t.c., are the investigated characteristics. The theoretical model of real holographic gratings, including the problems of shrinkage and deformation of grating and the nonuniformity of grating modulation, is formulated. The theory and the experiments are carried out both for holograms formed by dielectric particles and for holograms formed by colloidal silver particles. In conclusion the fundamental relations among the final diffraction properties of holograms and certain factors of production and processing of recording materials are indicated.
The inclusion of the arts in an otherwise scientific and technical conference is occasion to examine the relationship between art and science, and particularly in the newly emergent field of holography. Discussions concerning the "marriage of art and science" have been conducted before and surely will continue in the future. In this paper I wish to readdress the manner in which scientific rationalism interprets holographic art and the manner in which the arts can respond and contribute to further discussion. I will posit art holography as a kind of 'bride' to the more estabished and male-dominated technologies, a bride of unknown qualities. This paper presents a number of problematic conditions affect-ing art holography proper and examines its relationship to contemporary culture. Furthermore, the paper presents a theoretical schema for the development of a semiotic which can be employed in the study of display and art holography, a schema responsive to scientific rationalism and one which provides a point of further theoretical development of use value to both scientist and artist.
This paper will address the issues raised by the "commercialization" of holography that has taken place since the mid-1980's. The paper examines the range of these issues as they apply to the practise of fine-art holography, the author's area of expertise. The effect of mass-produced and readily available holograms on the public's perception of holographic art will be discussed in light of the presence of holographic images on credit cards and national magazine covers. A major portion of the paper will examine the specific issues raised by the commercialization and mass production of holographic art. These issues will centre on the professional, ethical and artistic implications of commercialized holography as they apply to the practice of fine art holography.
Buildings are built for many reasons. They can be built to impress potential clients, facilitate a production process, house people comfortably and/or economically or provide a background for the activities which they house. Most office buildings are deliberately dull. They are meant to be neutral, flexible spaces, easily altered to accomodate changing uses and tastes. The architectural intentions in this case are to separate functions and delineate hierarchy rather than to provide a pleasing work environment.
An exploration of the need to define a specific and critical language to describe the art of holography. Within any discussion of art, critical analysis must maintain an objective openess, particularily when the discourse concerns new media. To apply technological invention to art, new media is often without precedent on which to base criticism and bias. For this reason, holography falls prey to comparative rhetoric and established evaluation of other forms of imaging,as photography emulated the compositional romanticism of painting initially. Isolated and often misunderstood within the context of history, new media vascillates between legitimacy and curiosity in an attempt to create specific parameters to identify perceptual transition.
A survey of display holography shows that an arbitrary use of color lends little to the overall success of the intention of an image. Often the lack of concern regarding color detracts from the hologram and its ability to effectively communicate ideas in a visual format. Creative opportunities offered by pseudo-color reflection techniques and their impact on display holography will be considered. A review of the current procedures for producing pseudo-color reflection holograms is presented.
The first exhibition of holographic display was held at Seibu Museum of Art in Tokyo in 1975 and played a role of opening of the holographic era in Japan. This exhibition and the next big exhibition of holography held at Isetan department store 3 years later in 1978 were really epoch-making facts on holographic display in Japan. Since these two exhibitions, holographic display in Japan has come to attract attention of a lot of people to the new display media, holography. At that time, mass production technology of holograms had not been fully developed yet, and the hologram was so expensive that they were found only at the big event. Some companies and universities still continued research and development to have holograms get into practical applications of display media. Few years later, people became interested in 3-D displays and sometimes many peoples took an interest in holographic display, mainly mass produced embossed type holograms applied to the field of publications, book and magazine, etc. 3-D display booms occurred in the year of Tsukuba Science Expo'85 in 1985 and embossed type hologram became much popular. History of holographic display of Japan in terms of technical development and practical use on laser reconstruction hologram, rainbow hologram, multiplex hologram and lippmann hologram will be introduced.
Since the early sixties many companies in USA and abroad have tried to find a successful way to commercialize Holography. Most of them failed. The reasons are many - but are often due to the fact that there was neither a commercial major market for the holographic products nor the right kind of products. Since the beginning of the 1980's a small number of companies have begun a more wide and successful approach to Holography. What is the reason for this? And how can new holography companies learn from past experiences and in the future be more successful? Based on the experiences in New Dimensions, Laser Systems (a 3-year-old company, situated in Copenhagen) we have examined some of the greater aspects in building up a larger holographic organization.
As the Museum of Holography enters its second decade the holographic environment it serves is different to that of its first decade. The Museum must adopt its policies and programmes to this environment so that it fulfill its responsiblities to the public and to holography as the world focal point for the collection of holograms and the dissemination of information about holography.
The appeal of holograms has created a market demand that has spawned a fledgeling but flourishing industry. In this paper, we shall examine the composition of this industry and some of the possible results for holography economically.
Holographics North has developed new techniques for production and illumination of large holograms, up to 45"x60". These include construction of very large isolation tables, short arc mercury vapor lamps for large format laser transmission illumination and utilization of the facility for funded projects by scientists and artists worldwide.
This paper will present the characteristics of recording medium as well as the principle and features of recording, duplicating, displaying, copying, searching and other functions of the practical HUFS system. The medium is a silver halide emulsion with special proper-ties. Its resolution is up to 5,000 1p/mm and the first order diffraction efficiency of the unbleached emulsion is about 40-50% etc.. We can get the extremely bright daylight reflective holograms photographed and record more than 3,000 holographic points in a single ultrafiche with a size of 4"x6" which can store 3,060-12,240 pages of magazines in sexto-decimo. The reflective holograms and the ultrafiches can be preserved almost forever. This emulsion can be preserved for half to one year at the room temperature.
The development of laser diodes has been accelerated by their use in digital recording and reading technology. It is only natural, therefore, that the investigation of diodes as a source for holography increases as availability in shoreter wavelenghts and power increases. Use of the 780 nm wavelength region for Holographic Optical Elements (HOEs) and display holograms will be discussed in this paper. Exposing geometry, stabilization, and materials will be included.
A method for recording high efficiency multiplexed reflection holograms has been discussed. The image diffraction efficiency of reflection holograms has been enhanced by recording hologram of a real image of the object projected by another master off-axis hologram whose effective aperture is limited by a suitably shaped stop. The limited viewing area offered by these holograms is gainfully exploited for incoherent multiplexing of several objects on same recording plate. A technique for multiplexing reflection holograms is presented where the well known property of mirror like behaviour of interfering fringes is used. Two schemes of horizontal and vertical plane multiplexing have been discussed where the different multiplexed images do not overlap in the final viewing. Optimization of different experimental parameters to compensate for holographic reciprocity law failure and to achieve uniform diffraction efficiency in multiplexed restricted aperture reflection holograms has also been carried out.