Pulse portraits are loosely defined as holograms of live subject matter made with a pulsed laser. The first such exposures were accomplished by Siebert in 1968 followed'by Wuerker, Ansley, McClung (one of my supervisors at Hughes, 1973), Higgens, Gregor and others. In 1982 Hans Bjelkhagen produced white light reflection copies of pulsed masters in 8E75HD, 10 x 12 inches. Prior white light viewable copies had been made as transmission holograms by others but these reflection copies were especially impressive. At that time I toyed with the idea of using DCG as a copy medium and a year later began constructing the complete system which is now operational and expanding. Our system is much like the one Hans used initially except that the pulse energy is lower and the copying is done at 514 or 488nm as opposed to the 647nm line used in the prior system. Optical configurations differ and are evolving in second and third generation pulse and copy cameras.

Photoresist selection, recording, plating, and embossing meth-ods used for mass-replication of large-format embossed' holograms.

Brightness, S/1,4 and contrast of an image reconstructed from a rainbow hologram. using Agfa-Gevaert 8E56HD and Shipley MICROPOSIT-1350 (called AZ-1350 before.) photoresist are studied changing signal to reference ratio, exposure, dilution ratio of AZ-303A developer and its developing time. It is found that a qualified image can be obtained when signal to reference ratio is from 1:6 to 1:12 and the dilution ratio of AZ-303A developer is 1:5.

The widespread use of embossed holograms on credit cards has brought with it a huge boost of interest in holography in 1984.It is however easier to produce a counterfeit copy of these holograms able to deceive a busy shop-keeper than was originally realized by the credit card industry. The reason for this original lack of awareness is curiously because most holographers had been overlooking a phenomenon that they probably had all seen and which has existed ever since the first reflexion holograms.

A hologram viewing system is described which produces sharp, achromatic, full-parallax images from transmission holograms. The viwinc, system is based on the principle of dispersion compensation, and produces images of low aberrations and distortion. The viewing system is ideal for compact, portable displays, and eliminates the need for individual alignment of reconstruction lights. The quality of the image produced is largely independent of ambient lighting.

Techniques for production of large format stereograms are discussed. A graphic representation of the motion picture filming geometry is given. Applications in various fields are reviewed.

A multiplex hologram is synthesized by using a special optical system from an original film composed of a series of conventional photographs taken from different horizontal directions. An automatic apparatus for synthesizing multiplex holograms is built and fundamental properties of reconstructed images such as distortion and resolution are studied for both ordinary and medical objects. Some techniques to compensate the distortion are developed.

Nevertheless it is holography which is regarded as a theme of 3-dimensional image, it had taken much time before it was regularly used as a display. Practical instances, which are worthy of special mention, have lately appeared at the same time from both Japan and U.S.A. One of them is to be used in the cover of the National Geographic, and also used in the jacket of some music records.

Begins by defining which red, green, and blue wavelengths are required for the proper hue blending, determining an appropriate Bandwidth, and processing to attain this while maintaining sufficient diffraction efficiency. Procedure is outlined for the multiple exposure of a color reflection hologram that contains the three primarys. Where two primarys overlay producing the secondary hues and attaining a "White" where all three primarys overlay. The resulting hues are analyzed on a spectrometer.

Techniques are described to expedite the process of replicating multicolor reflection holograms for limited production runs. Specifically the use of contact masters and scanning optics, long used by the integral and dichromate holographic industries, are adapted.

Automated defect detection in highly repetitive subject formats such as integrated circuit photomasks has been the subject of numerous papers in the past.^1-6 Techniques previously reported generally fall into two basic categories - namely digital and optical processing methods. Digital techniques involve the bit by bit or pixel by pixel comparison of information associated with two subjects. One subject is generally a highly magnified image of a portion of a single die. The other subject is either a similar image of a reference die, such as an adjacent die, or the digital data base used to generate the photomask. Optical processing methods differ fundamentally from digital techniques in that the subject information is manipulated not in the image plane, but in the Fourier Transform plane normally formed by a lens. The optical information processing discussed in this paper is limited to spatial frequency filtering.

A "portable" holographic microscope with a nanosecond Q-switched ruby laser illuminator has been assembled. The system has been used to record dust phenomena under field test conditions.

Reflecting tubes and ducts can be used to holographically record three dimensional images of poorly accessible objects to microscopic resolutions. Tests with hollow glass tubes and ducts (made from front surface mirrors) indicate that the resolution of the holographic system is significantly improved.

Historically, holograms have been recorded on silver halide emulsions which require darkroom processing. In recent years, thermoplastic recording procedures have matured and commercial devices are now available. A thermoplastic device records the light intensity pattern in the hologram solely by using electromechanical forces and is an electronic device. The hologram is prepared for exposure, processed, and fixed electronically by a "dry" process, in place, within seconds. Recordings can be inspected immediately and data reduction initiated. In addition, poor recordings may be erased repeatedly until the desired hologram is produced. Since the plates are electronically activated, double plate holographic interferometry is implemented in-situ; as the rear plate is exposed before the front plate is sensitized. The plates are mounted in adjustable receptacles allowing for fringe control in holographic reconstruction. This paper describes the development and applications of a double plate thermoplastic holography device using a commercial single plate thermoplastic device.

The technique of holographic interferometry provides a means for noninvasive measurement of the air density distribution in the flow field in the vicinity of an aerodynamic model. A test of the applicability of this technique was the objective of this investigation. A holographic interferometer was installed in the 2- by 2-Foot Transonic Wind Tunnel at Ames Research Center. Several tests were conducted with this system on two axisymmetric models, one at subsonic and the other at supersonic speeds. Holograms were made of the flow field around the model for several test conditions. These holograms were reconstructed into interferograms in the laboratory. The fringe distribution (a measure of local densities) from a number of interferograms was digitized for subsequent data reduction. A computer program based on the Fourier transform technique was developed to convert the fringe distribution into a three-dimensional distribution of air density around the model. These results will be presented in this paper.

A truly noninvasive measurement technique for plasma velocity has not been demonstrated. Plasma velocities have been inferred using laser Doppler anemometry or photographic analysis of the position of smoke or small particles. This paper describes an alternate method based on the refractive index change created in a plasma by a gaseous probe material injected into the plasma. This disturbance of the refractive index can be monitored using interferometry. A multipass real time holographic interferometry system was used to follow the changes of the interferometric pattern, and the data was recorded using high speed cinematography. A transparent model of an industrial plasma torch was employed in these studies, and a number of different types of trace gas materials were used to track the plasma flow. Using a combination of multipass interferometry and a laser line absorbing gas, sufficient interferometric sensitivity was obtained to determine plasma velocities in the 100 m/s range. Based on these results, a working plasma torch was constructed. Further studies are planned using this torch and actual plasmas.

The size distribution of a particle field hologram is obtained with a Fourier transfor-mation of the Fraunhofer diffraction pattern of the reconstructed hologram. Off-axis absorption holograms of particle fields with known characteristics were obtained and ana-lyzed with a commercially available instrument. The mean particle size of the reconstructed hologram was measured with an error of ±5%, while the distribution broadening was estimated within ±15%. Small sections of a pulsed laser hologram of a synthetic fuel spray were analyzed with this method thus yielding a spatially resolved size distribution. The method yields fast and accurate automated analysis of particle field holograms.

Vertex detectors with good spatial resolution are ideal devices for the detection of short-lived particles (mean lifetime > 10^-13 seconds, mean distance traveled before decay z 140 pm) produced in high energy interactions. The bubble chamber equipped with high resolution photography is one such vertex detector. However, improving the resolution in photography results in a very rapid decrease of the depth of field, thereby rendering most of the chamber optically inaccessible. Using holography instead of photography remedies this problem by decoupling resolution and depth of field. This paper reports on our recent work in the use of a two beam holographic technique for a large freon bubble chamber (80 cm diameter and 100 cm deep). This bubble chamber is the vertex detector for a hybrid spectrometer system that would be used for two of our forthcoming experiments at the Fermi National Accelerator Laboratory: the first to search for the short-lived charm particles, and the second to establish the existence of the T neutrino by observing the decay of the T lepton. We demonstrate that a 30 pm resolution could be achieved throughout the entire volume of the chamber. Specific details pertinent to achieving this resolution are also discussed. We also report on the construction of a semiautomated high-precision measuring apparatus that would be used to scan and measure bubble chamber holograms.

The three dimensional imaging capability combined with enormous information storage capacity and the related very high resolution of images when they are correctly reconstructed, combine to make holography an inspection tool of immense power and utility in capital intensive industries. This paper describes work, in the U.K. electricity generating industry, aimed at enabling high grade holograms to be routinely recorded in a wide range of industrial situations where high speed acquisition of visual data is desirable. Specific applications to be described are holography of nuclear reactor cores, and of irradiated fuel elements for inspection after withdrawal from the reactor. Accurate reconstruction of images and precise, three dimensional measurement of reconstructed images in a laboratory environment is then undertaken with computer controlled micromanipulator equipment traversing a television camera within the real image. Measurements of a metre long fuel element to within 0.1 mm have been demonstrated and resolutions of 50 1.p./mm have been obtained on the reconstructed object. The paper describes the engineering required for in-reactor inspection where the pulsed ruby laser used to record the holograms is routinely alignec to a 15 m beam relay and remote holographic head. The requirements for accurate 3-dimensional reconstruction and hologrammetry are described and plans for automated measurement and inspection using image enhancement techniques are discussed.

A simple procedure, using holographic interferometry, for measuring diffusion in transparent liquids is presented. A Mach-Zehnder interferometer and A CCD linear array are used to record the moving fringes, and the data is processed automatically on a micro computer. The diffusion constant is determined from the velocity of the fringes which are observed in real time. Results of measurements on NaCl solutions demonstrate the usefulness of this technique.

Several recent applications of holographic interferometry to nondestructive testing are described and the basic methodology is discussed. Applications to the detection of cracks, particularly in ceramic materials, including a crack 50 μm in depth are given. A non-destructive method to quantify the gradual erosion of calcareous stones exposed to acid rain is presented.

This paper presents a new technique which eliminates the ambiguity in holographic fringe interpretation. The technique is based upon generating a high density linear phase carrier. Introduction of the carrier results in the formation of a fringe pattern which has mono-tonically increasing fringe orders. Any deformation of the object under study produces a corresponding perturbation of the carrier pattern. If the carrier dominates, the perturbed pattern continues to have monotonically increasing fringe orders and thus allows the fringe order to be determined at any point without ambiguity. The phase change due to deformation alone is obtained by subtracting the known linear carrier from the modulated fringe pattern. Elimination of fringe ambiguity will pave the way for automatic data acquisition in holographic interferometry.

Optical precise and rapid method for the inspection of shape error of gear tooth surfaces is developed. Laser light reflected specularly from the gear tooth surfaces is modified to converging spherical wavefront, which converges to a small point. The light intensity through the pinhole put at the position of the converging point is measured photo-electronically. The decrease of the electronic signal coresponds to the surface shape error of the gear tooth.

A number of experiments in vibration analysis are discussed where different methods like hologram interferometry, impact testing, acoustical recording, FEM-calculations are compared to results obtained by means of an instrument based on image-plane, time-average hologram recording on a TV-vidicon like ESPI (electronic speckle pattern interferometry). The instrument, "VibraVision", offers distinct advantages in vibration studies.

In normal double exposure holography with impulse loading it is very difficult to locate defects because the fringe clutter, due to random motion between exposures, often swamps the fringe shifts caused by the presence of sub-surface defects (cracks, debonds, etc.). We attempted to simplify the defect location problem by developing a concept more amenable to automatic readout techniques. Our approach to incorporate this change is quite simple. We swing the object beam between the two exposures which adds a linear fringe to the reconstructed image. Proper selection of the fringe frequency (angle of object beam swing) and the loading force creates a recon-structed image laced with linear fringes with fringe shifts at the defect locations which are highly visible. We will describe the theory of the process. Experiments performed with a static load illustrate that the defect is seen as fringe shifts on a linear carrier. Both through cuts and rear surface cuts in a metal test plate were used to simulate defects. We further show that the defects have characteristic Fourier signatures different from those of the carrier.

We present results from our program on fringe linearization for double exposure holographic interferometry for the detection of defects in large areas of metal structures. A model is developed to simulate the expected holographic results, and its predictions are compared to the observations as an aid in refining this nondestructive evaluation procedure. The test specimens are aluminum plates containing circular holes and supported on three sides. Between holographic images a bending moment is applied across the hole. The specimens contain either a through cut or a part-through cut designed to approximate through and part-through cracks respectively. The interference holograms are created by double exposure. Between the first and second exposures the bending moment is applied, and the incident beam is rotated creating fringes which result from specimen deformation and beam rotation. The degree of beam rotation controls the extent to which the fringes are linearized. The supporting finite element modeling and analysis is performed using the ANSYS computer code and plate elements. Fringe linearization is accomplished by adding a rigid body deformation to the deformation field. We will discuss the excellent agreement between experimental FLI results and the finite element predictions for the case of a specimen with a part-through crack in the back surface and not optically visible.

Holographic FLI technique provides a means of reducing fringe clutter noise. Holographic interferometry measures position changes of the order of the wavelength of the light used. Moire techniques provide a means of desensitizing holographic interferometry. Moire techniques may be employed with FLI with the objective of automating the defect detection process. It may be necessary to employ a spatial frequency filtering step to remove fringe clutter noise.

The manufacturing technique and experimental results for a narrow band holographic reflection filter which is linearly tunable over the 1.2-1.6 micron wavelength region is described. The filters have greater than 90% reflection efficiency with spectral bandwidths less than 20nm at full width half maximum (FWHM). One application of this component is as a single channel selector for wavelength multiplexed optical fibre systems.

Reflection holograms of the volume-phase type fabricated with dichromate gelatin have the advantages of achieving efficiencies very close to 100%, of very low noise, and due to its wavelength selectivity, of a chromatic dispersion which can be acceptable in many applications. During several years, the process for production of these holograms has been investigated with the goal of controlling it and achieving good quality and repeatability. Holo-graphic spherical mirrors with dimensions larger than 32" were used in the "Holographic Pancake Window" optical simulator suitable for the training of pilots. These holograhic spherical mirrors were also built as compound holograms with a "white" spectral response very similar to the conventional mirrors. Prototypes of holographic combiners were fabricated and analyzed. Holographic mirrors with optical configurations analog to plane, spheriical and aspherical mirrors are also manufactured to be used as notch filters which will selectively reflect very narrow spectral frequencies, for example, laser radiation. They offer the advantages of high optical densities with high field of view coverage and high photopic transmission.

NTS Super-High Efficiency (SHE) Holographic Technology consists of Dichromated Gelatin (DCG) Bragg Reflection Holograms possessing properties that maximum hologram diffraction efficiency (reflection, in good approximation) is close to 99.7% and optical scattering/ absorption losses are below 0.2%. Hence, NTS Reflection Holograms can achieve close to the theoretical limit for several important holographic applications, including dichroic/ polychroic mirrors, high-reflection spectrum-selective filters, spectrum-splitting PV/TPV holoconcentrators, large holographic mirrors for space applications, holographic heads-up displays, holographic fiber couplers, holographic optical elements (HOEs) holographic coders/decoders, holographic window films, holographic chromatic filters, etc. In this paper, we discussed the application of SHE Holographic Technology to concentrator optics including especially solar applications.

Diffraction pattern sampling provides a feature space suitable for object classification, orientation and inspection. It allows significant dimensionality reduction. These properties are best achieved by the use of specifically-shaped Fourier transform plane detector elements and this can be realized with considerable flexibility, reduced size and improved performance by the use of computer generated holograms.

An optical system containing multi-faceted holographic optical elements (HOEs) was constructed to correct for aberrations introduced by a non-flat window in NASA Laser Doppler Velocimetry (LDV) experiments in an internal combustion engine. For this experiment, two green beams separated by 82 mm in a vertical plane, and two blue beams separated by 82 mm in a horizontal plane, are brought into coincident focus inside a thick walled sapphire cylinder. The focal power to bring these beams to a common focus and the aberration correction required by the presence of the cylinder were built into the holographic elements. A modular optical breadboard system was configured to fabricate, test, and use the custom made HOE's. Additional HOE's were also fabricated to provide aberration correction and color separation for the multispectral output waves emerging from the focal volume. Compensation for the birefringence of a thick sapphire cylindrical window in the experiments is also accomplished. A general system such as we have built is useful wherever high efficiency, localized optical correction of wavefront errors is needed in LDV or other optical experiments.

By combining advances in lithography and electromagnetic grating theory, we have recently demonstrated the ability to produce highly efficient binary gratings and binary lenses for use at 10.6μm. Electromagnetic theory predicts that binary gratings with the proper parameters can achieve a first order diffraction efficiency of nearly 100%. If the periodicity of the grating is on the order of the radiation wavelength, all of the orders become evanescent except for the zero and +1st orders. By choosing the depth to period ratio and duty cycle properly, the zero order can be suppressed, placing virtually all of the incident radiation into the 1st diffracted order. Theoretical calculations have been done only for constant period gratings. However, assuming a lens pattern to be a minor perturbation of a grating, we succeeded in producing an F/5 binary lens with a diffraction efficiency of 96% at 10.6pm. Furthermore, because of the high efficiency of these elements, it becomes practical to consider using more than a single diffractive element in a system. We have constructed a simple afocal telescope from two binary lenses. The telescope has a 2 inch entrance aperture and a magnification of 5. A final point to be considered is the wavefront quality of these elements. Electron beam machines, which are used to write the lens patterns, are designed to draw the pattern in a raster fashion. This quantization sets a limit on the quality of the lens pattern.

A honeycomb close-packed microstructure can be recorded in a positive photoresist layer by a simultaneous exposure of three coherent laser beams. The structure consists of parabolic shaped depressions in the surface. By replication and embossing techniques, it is possible to impress the mirror image of the microstructure into plastic, such that the top surface consists of parabolic shaped posts, or microlenses. The size of each microlens can be varied from around one micrometer to a millimeter or more. There are wide-ranging applications for such regularly-spaced and precise structures, extending from solar concentrators to three-dimensional imaging devices.

A reflective computer-generated holographic element modifies both the phase and polarization of a high-power, coherent microwave beam. The phase is modified by variations in the surface profile and the polarization is modified independently by a polarizing grating structure imbedded in the surface.

In this paper we discuss the properties of optical elements fabricated by holographically recording an ultra-high spatial-frequency pattern in a photoresist mask followed by reactive ion etching to transfer this pattern into the surface of a quartz substrate. Such optical elements are envionmentally durable, potentially easy to replicate, and exhibit diffraction efficiencies in excess of 85%. In addition, two other properties are reported. Such elements at normal (00) incidence are antireflective, with broadband reflection coefficients as low as 0.035%. Also, the elements exhibit artificially produced birefringence making them useful as wave plates. These results may be particularly significant in the UV and IR, where damage-resistant antireflection coatings and transparent birefringent materials may not exist.

Aspheric Holographic Optical Elements (HOEs) have been applied in areas such as optical testing, optical processing, and imaging. The aspheric HOE is generally represented during the design process in terms of its object and reference construction wavefronts, which may be defined in a number of ways such as point source locations, wavefront-forming lens surfaces, or analytic phase functions. We have pursued a design and fabrication process which takes advantage of the design flexibility provided by arbitrary analytic wavefront definitions. The goal of this process is to produce large, efficient, generally aspheric HOEs without the long lead times and high costs associated with fabricating generally aspheric wavefront-forming lenses. The physical realization of the HOE wavefronts is accomplished through a combination of readily-available lenses and computer-generated holograms (CGHs). An optical processor is employed in the wavefront-generating hardware which serves both to filter out unwanted CGH diffracted orders and to copy the filtered wavefront into a high-efficiency dichromated gelatin hologram. The processes of HOE wavefront definition, optical processor design, and CGH fringe generation are described along with practical limitations of the concept.

We report here the development of an integrated capability for writing computer-generated holograms (CGHs) using either of two commercially available electron-beam lithography systems. These binary, chrome-on-glass holograms have been used extensively for aspheric optical testing and also have applications to the interferometric recording of holograms. Algorithms are described for encoding CGHs for e-beam writing. Limitations of e-beam CGH fabrication are discussed. A self-contact lithography and ion milling process is described for converting chrome-on-glass holograms into 40-percent efficient, environmentally durable, all-glass holograms.

In the early seventies a number of researchers noted that DCG was in some cases an ideal material for HOE fabrication. B.J. Chang and Andres Graube both did extensive characterizations of the material and many others have contributed since then. A large number of HOES have been made since then and a few are in industrial or commercial machines already. It would take a very long time to describe all the variations and applications that have been reported. In this paper we discuss only a few applications where non-standard practices may have been employed in meeting the design objectives. The emphasis is on the fabrication solutions and on any unusual or previously thought unlikely results.

The development and construction of a production process to manufacture holographic optical elements in dichromated gelatin for Head-Up Displays requires that a tight control over the spectral tuning, spectral bandwidth, diffraction efficiency, scatter, cosmetic appearance and environmental stability be established. Once control is established, it becomes possible to produce significant changes to the tuning position, spectral bandwidth and diffraction efficiency, so that holographic optical elements can be produced for a range of applications. This paper examines several holographic optical elements produced by Pilkington P. E. Limited, including retrofit combiners, contrast enhancement filters and narrow band reflection filters. The construction, holographic specification and performance of each of these holographic elements will be outlined and discussed.

A practical, industrial manufacturing process for holographic optical elements based on dichromated gelatin has now been established to meet the exacting standards and tolerances needed for current Head-Up-Display applications. This process is now also being used to produce holographic optical elements for a number of other applications. The material requirements are very demanding for holographic optical elements of high quality and performance. A better understanding of hologram formation in dichromated gelatin is leading to better control over the performance range which can be achieved. Holographic optical elements whose performance closely matches theoretical models assuming uniform fringe structure will be described as well as examples of holographic optical elements, whose performance can only be described by assuming a non-uniform fringe structure. Such controlled non-uniform fringe structures are advantageous for some applications. Techniques have been developed to produce dichromated gelatin holographic optical elements with a very wide range of characteristics for new applications. High quality reflection holographic optical elements have been produced in gelatin films from less than 5 μ to greater than 100 μ in thickness. A wide range of combinations of diffraction efficiency and bandwidth can now be produced and holographic optical elements can be tuned over the whole visible spectrum and into the near infra-red. Holographic optical elements on plastic substrates have also been made. Dichromated gelatin transmission holographic optical elements have been produced with diffraction efficiencies approaching the theoretical maximum for both planar and Bragg holograms. Applications for both reflection and transmission holographic optical elements are described.

Holography with a new photopolymer system, DMP-128, will be described. Films of DMP-l28 are coated on either solid or flexible substrates from an aqueous solvent. The resulting films, when stored dry, have a shelf life that exceeds nine months. The dry films are inactive and must be incubated for a few minutes in an environment of approximately 50% rh before laser exposure. Recording is possible with eitheF blue (442nm, 488nm), green (514nm), or red (633nm, 647nm) laser light. Exposure of 5mj/cm is sufficient for high diffraction efficiency (80%-95%) transmission holograms, while 30mj/cm2 is required for bright reflection holograms. It is not necessary to exclude atmospheric oxygen during hologram recording. Refractive index modulation of 0.03 is routinely achieved. After laser exposure a uniform white light illumination is used to complete the photo-polymerization. A single processing bath yields holograms with good environmental stability. An additional processing bath yields images with exceptional resistance to high humidity.

The photographic technique of Lippmann dating from the period 1890-1910 is re-examined in the light of recent experience. Modern chemical modulation techniques can create photographic Lippmann layers of remarkable reflectance. In the background there remain many unanswered questions in relation to the bandwidth of the incoherent light recorded in those early experiments. It is reiterated that coherent sources appear to be essential to create the conditions necessary for arbitrary wavefront reconstruction but some success has been achieved in copying holograms using Lippmann techniques together with metallic relief image surfaces.

This paper describes a technique for generating broad spectral band Fourier holograms with an encoded white light source. Since this technique utilizes primarily white-light construction and reconstruction process, it is quite suitable for color Fourier hologram image reconstruction. Experimental results are also given.

In this paper we present an holographic system based on the properties of optical propagation in birefrigent media. We have called it conoscopic after the conoscopic figures which are obtained when a spherical wave propagating through a birefrigent crystal, is observed through crossed polarizers. The idea can be summarized by saying that we replace the object and reference beams of coherent holography by the ordinary and extraordinary beams propagating in birefrigent media, two beams that are naturally coherent one with the other.

The last years show an increasing application of white light holograms as security features for credit cards. The holograms raise the level of security and they prevent more or less fraud and counterfeit. Two different methods of application such as embossing on cards or incorporation in cards are described. The principal differences between the two methods i.e.; long production-runs versus short production-runs will be elaborated. Our own development of a step-and-repeat camera to produce white light holograms will be elucidated.

This paper presents a new method for the pseudocoloring of an encoded phase-picture. ThQ method is carried out only with one white-black film and once-through encoding. The encoded film is transformed into a phase encodes transparency, then it is put on the input-plane of a white light processor, and the density pseudoculor image is obtained on the out-put-plane by spatial filtering of the Fourier spectrum. This method has born used in the processing of the films of astronomy, remote-sensing, biology, and medicine, and good results have been obtained.

This paper describes a real-time processing with a hologram which generates a phase conjugate wavefront to compensate the aberration through a phase distorting medium. Good-quality reconstructed image is obtained. Comparisons with the conventional holographic procedure, using silver halide emulsion, and the "degenerate four-wave mixing (DFWM)" phase conjugation process are presented.

This paper attempts to point toward future technological developments that might accelerate the commercial applications of holography. Conference attendees are asked to participate in an "Expert Survey", the purpose of which is to predict what technological advances are expected to bring about new applications of holography, or to significantly improve current applications. In addition, the survey assesses the time frame within which these advances are expected to occur, and describes how these technologies interact with each other. Part One of the paper explains the rationsl for this survey, and solicits the participation of the SPIE conference attendees in structuring the survey format. Part Two -- to be published in the near future -- will present and analysis of the survey results.

In this paper we consider various applications of holographic techniques to the problem of soft x-ray imaging. We give special attention to imaging biological material using x-rays in the wavelength range 24-45Å. We describe some experiments on formation and reconstruction of x-ray holograms and propose some ways in which holographic techniques might contribute to the difficult problem of fabricating optical elements for use in the soft x-ray region.

The author presents his experiences in setting up a course in basic display holography within the School of Photographic Arts and Sciences at the Rochester Institute of Technology. The course goals, outline and projects are discussed as well as the future prospects for advanced course work in applications areas.

A description is given of a laser system used to produce interferograms of a large centrifugal compressor, powered by an industrial gas turbine engine with a dominant system response at 168Hz. The results demonstrate a travelling wave generated within the feed pipe to the compressor. Finally the description of a potential real time double pulse systeu is presented.