It is well known that particular choice of laser wavelength combination is of great importance in making color holograms. Previously, it was found that the 532 nm wavelength was most suitable for green. Herein we report the results of experiments performed in search of the most suitable blue wavelength. Also discussed will be the procedure and configuration used for the experiments.

Throughout `EI' '92, '93, '94 and '95, we have been presenting an experimental holographic movie system as a tool to estimate the picture quality of moving holographic images as a step towards holographic TV. Therefore these presentations can be seen as experiments for holographic movie system. They present holographic move devices as well as instruction on how to make holographic movies on film. Holographic movies are possible as we will report in this presentation. Throughout holographic movie devices I, II, III and IV, the same equipment and technology has been used. This will be recognized and appreciated by holographic researchers. Nowadays to record holographic images, it is best to use holographic film (in the case of animation, there is no other method). Through this method in each new version, we have been trying to broaden our expressions and artist's image in using new technology and take a further step for better holographic movies on film. In the future holographic movies will become popular. But now in their research phase we are working on animated movies as not only an presentation of technique but also as an artist's expression as well. We are making these technology with the general concept and intention of appealing to the senses of all people. These are not only holographic animation pieces but also 3D sounds and a construction of images in time. We have approached this concept with a most positive attitude.

Holographic movies can be seen as a tool to estimate the picture quality of moving holographic images as a step towards holographic television. The authors have previously developed three versions of an experimental holographic movie system, and this paper is a report on an improved version 4 of the system. The new version features a newly-developed projection-type display with a retro-directive beaded-screen, and an automatic film driver unit which moves perforated 35 mm holographic film intermittently with a shutter. A twin diamond-shaped hologram format, which was developed in the earlier version 2, is adopted for the films. The films comprise a series of reconstructed moving holographic images with minimal blurring. The optical arrangement and structure of the version 4 system enable the viewers to watch the film images in an open space, which in turn relieves them of the psychological pressure they felt with the previous three versions, when they had to squint into a narrow window built into a wall on the side of the device.

This paper presents a unique approach to the production and display of a hologram movie. Motion was provided by rotating a 3D object in steps between exposures. Strip holograms were made on 70 mm AGFA 8E75 Holotest roll film. Each hologram was about 11 mm high and 55 mm wide. The object was rotated two degrees, while the film was advanced, between successive exposures. A complete rotation of the object was recorded on 180 holograms using the lensless Fourier-transform construction. The ends of the developed film were spliced together to produce a continuous loop. Although the film moves continuously on playback and there is no shutter, there is no flicker or image displacement because of the Fourier-transform hologram construction. The movie can be viewed for as long a time as desired because the object motion is cyclical and the film is continuous. The film is wide enough such that comfortable viewing with both eyes is possible, enhancing the 3D experience. Viewers can stand comfortably away from the film since no viewing slit or aperture is necessary. Several people can view the movie at the same time. Speckle is reduced due to the film motion.

In this paper the results of color reflection hologram recording on a single layer fine grain silver halide PFG-03c emulsions are reported. Some parameters of this material, that are of importance for recording the high quality color holographic display, have been studied experimentally, in particular, the absorption characteristics of both developed and non- developed layers and exposure characteristics for single and multicolor recording, as well as joint function of the angular and spectral selectivity of the reflection holographic gratings.

The conical holographic stereogram is considered an interesting example for holographic display. To form a conical holographic stereogram, the 2D images are recorded on a series of slit holograms following a circle pattern. This procedure however, introduces some problems. It causes the reconstructed image be composed of an assembly of different image portions reconstructed from the slit holograms, and since the slit holograms are arranged in a conical structure, the reconstructed image is seen widened at the top and narrowed at the bottom. To cancel the distortion and correct the perspective view, an image processing is performed on the original set of images. By picking up pixel data of successive frames of the original set, a new set of 2D images is formed.

A prototype model of the holographic 3D printer (holoprinter) is presented and the experimental results are reported. The holoprinter is developed for the purpose of a peripheral device to produce 3D image hard copies of computerized data. By the prototype, the practical problems such as the requirements for the vibration isolation and the time for printing, are investigated. Through the experiment, we demonstrated that 3D images of high diffraction- efficiency can be recorded without air-floated optical bench. In addition, a new optical system for high-speed printing is proposed. Using an array of lenslet, several elementary holograms are exposed in parallel, resulting in the reduction of total printing time.

I believe that the stereogram's gradual increase in popularity over the years is due to the fact that they don't display a lot of the characteristics that are usually criticized in normal display holography. Also fewer restrictions in subject matter means that almost any object or scene that can be photographed can be recorded. With more and more holographers using stereograms, existing photographic techniques can be employed for creative use. Using stereograms gives the artist/holographer increased creative possibilities and using existing photomontage techniques these possibilities increase even further.

Method for the recording and reconstruction of 3D images of objects when using a so-called reference-free selectogram is suggested. According to this method, the light scattered by the object is filtered by a horizontal slit and is then split into two components with the help of a diffraction grating that is positioned just in front of a thick-layered photographic plate. The interference pattern that originates as a result of the interaction of the components formed by the diffraction grating is recorded in a light-sensitive material in a form of a 3D deep hologram. The reconstruction of the selectogram is performed by the light scattered by a diffusing screen that is positioned in a so-called window of the system. The analysis of the processes of the selectogram recording and reconstruction in a coherent and noncoherent light is carried out and some properties of the reconstructed image are considered. It is also shown that the structure of the 3D hologram recorded by the system does not practically depend on the wavelength of the recording light. The advantages of the reference-free selectogram are low requirements as to the coherence of the recording and reconstructing light and the insensitivity to the vibrations of the setup during the recording.

Computer generated holograms offer the potential of producing holographic optical elements for use in head up displays, laser scanning and optical computers. They are normally produced using expensive and complex materials and equipment. In this paper, the production of CGHs using 35 mm black and white film without elaborate equipment is demonstrated and the results examined.

A novel technique is described for laser beam cleanup, the nonspatial filter, which is based on the Bragg selectivity of thick holograms. Unlike pinhole and fiber spatial filters, which employ lenses and apertures in the transform plane, nonspatial filters operate directly on the laser beam. This eliminates the need for laser beam focusing, which is the source of many of the alignment instabilities and laser power limitations of spatial filters. Standard holographic materials are not suitable for this application because differential shrinkage during processing limits the maximum Bragg angle selectivity attainable. This paper describes a new technology which eliminates the problem of differential shrinkage. This technology is based on the use of a rigid porous substrate material, such as porous gas, filled with a light sensitive material, such as holographic photopolymers or dichromated gelatin. We report preliminary results of holographic nonspatial filtering of a laser beam in one dimension, with an angular selectivity of less than 1 milliradian.

The efficiency of diffuse-objects holograms recorded in bleached silver halide emulsion is analyzed as a function of the polarization state of the readout wave. An important source of noise founded in these holograms, when they are processed with rehalogenating bleaches, are noise gratings which are very sensitive to polarization. The dependence of signal-to-noise ratio on the relative polarization between the construction and reconstruction beam is showed too. Experimental results are presented which permit to choose the better conditions of reconstruction of this holograms.

Holographers have an expectation that holography might be a photography of tomorrow. But now, holography isn't still popular because of difficulties of its making process. With my experiment of teaching holography at Art University, good results are obtained by the use of holography-camera instead of conventional optical kit. This paper illustrates the outline of holo-camera and its use.

Optical forces, such as radiation pressure and the gradient force, are used to trap microscopic size dielectric particles. Regular arrays of optical traps can be constructed interferometrically, and more complex assemblages of traps could be made through holographic-type set-ups. Such optical-well arrays are useful in writing and erasing dynamic gratings. Two-dimensional `optical crystals', composed of monodispersed polystyrene spheres in water, display high diffraction efficiencies and low noise level, thanks respectively to a very high index modulation, and to the very small size dispersion of the scatterers. Many dielectric micro- objects can be arranged in such trap assemblies to form diffractive structures. This is the case in particular for biological materials such as bacteria or other organisms currently trapped with laser tweezers. The possibilities of manufacturing 3D diffractive structures are explored.

Displaying animated holographic 3D images by means of opto-electronic devices causes serious problems because of the huge amount of data of the hologram and the inadequate resolution of the display. One possible solution is to limit the reconstructed 3D image to discrete horizontal perspectives. In this paper a 3D display is proposed which enables the creation of holographic stereograms with novel high-resolution diffraction light modulators. The modulators perform simultaneously the image generation and the direction-selective display of 2D perspective views in the same way as holographic stereograms. The modulators are based on optically defined binary phase gratings whose diffraction properties are altered by an LC layer. Switchable gratings with periods down to 1 micrometers and high diffraction efficiencies and extinction ratios have been demonstrated. Until now the hologram synthesis itself could not be accomplished because of the lack of a sufficiently large electronic addressing matrix, but the basic modulator principle underlying the synthesizer has been demonstrated experimentally. The optoelectronic hologram synthesizer scheme, the diffraction light modulator construction and the diffraction properties achieved of the fabricated modulators will be explained.

Cylindrical holography has been utilized to capture 180 degree(s) field of view of high speed ballistic events. In this paper, we detail the methodology, design, and experimental results for a cylindrical hologram system that captures the fragment fields behind a penetrated armor plate. It is critical to use the wrap-around approach for proper test evaluation because of the possibility of large armor chunks blocking other fragments. An 18 ns pulse width, 3 Joule ruby laser is used as the illumination source for these 45.7 cm diameter holograms. For this application, the primary challenge has been the mitigation of the large flash caused by the projectile/target interaction. Several flash reduction techniques are discussed including narrow- band and neutral density filtering. Experimental results for this ongoing effort are presented.

An experimental 16 to 16 single mode fiber interconnect is being implemented. The switch structure involves the deflection of the incoming channels by two successive photothermoplastic holograms situated among two linear arrays of sixteen 650 by 650 micrometers holograms, with a 750 micrometers spacing. A reconfiguration time shorter than 10 ms for one couple of interconnection holograms has been demonstrated, with a diffraction efficiency exceeding 20% at a readout wavelength of 1.32 micrometers . Linear fiber and microlens arrays are required to perform a global collimation of all incoming and outgoing beams. We have interconnected two 16 fiber arrays situated at a distance of 12 cm (compatible with the holographic switch design) with 8 dB connection losses by using arrays of refractive microlenses of 2.9 mm focal length. Thus, in the final system the overall losses can be kept lower than 25 dB, which is compatible with optical amplification. An optical addressing system has been designed for the reconfiguration of the holograms. It involves two bi- dimensional deflection subsystems. The first one is based on two acousto-optic deflectors and performs the control of the grating period; the second one involves to moving mirrors and allows to select what hologram is to be exposed. The global reconfiguration time (for the 32 holograms) is expected to be lower than 100 ms.

Complex compliant structures have often been very difficult to characterize with the usual radiographic, ultrasonic, or similarly macroscopic analytical techniques. Such structures can present great variations in density; extremes in bond types and strength at interfaces; deeply buried anomalies within the volume of the compliant structure itself; as well as unusual geometries which obviate various analytical methods. These are ideal requisites for analysis with both real-time and multi-exposure holographic techniques. The operational and material characteristics of a complex bonded component of virtually any configuration and size depends on its true structural dynamics. These dynamics are directly related to the mechanical and physical interfaces between the supporting and compliant parts. Such complex assemblies require sophisticated bonding and processing of compliant and rigid materials. Understanding the effects of structural anomalies and defects is of critical importance, and a non-destructive method for the visualization of anomalous structural characteristics would be of great value in both development and testing. Holographic interferometry has presented itself as a viable and useful method for the realization of this type of information.

The ICVision system is a diffractive display based on VLSI and liquid crystal technologies which displays the functional equivalent of a real-time holographic stereogram. We have previously reported several static ICVision displays, based on the partial pixel architecture, that displays a fixed 3D scene. Herein we report the first real-time implementation of an ICVision display (also based on the partial pixel architecture) that displays the functional equivalent of a real-time holographic stereogram. The device is constructed using a diffractive optical element and a separate liquid crystal display. The animated sequence is pre-computed then played back in real-time using standard VGA on a 80386 or higher PC. The display, drive electronics, and computer may be battery powered making the display suitable for portable use.

We propose parallel architecture, which consists of small display units, to make up a large electro-holographic display. It is difficult to make a large 3D display using electro-holography because it requires a lot of calculations, broad bandwidth, and restrictions of optical and mechanical elements. In this paper, we discuss the problems, then show basic idea of architecture and preliminary experimental results.

This report describe the hardware architecture and software implementation of a hologram computing system developed at the MIT Media Laboratory. The hologram computing employs specialized stream-processing hardware embedded in the Cheops Image Processing system--a compact, block data-flow parallel processor. A superposition stream processor performs weighted summations of arbitrary 1D basis functions. A two-step holographic computation method--called Hogel-Vector encoding--utilizes the stream processor's computational power. An array of encoded hogel vectors, generated from a 3D scene description, is rapidly decoded using the processor. The resulting 36-megabyte holographic pattern is transferred to frame- buffers and then fed to a real-time electro-holographic display, producing 3D holographic images. System performance is sufficient to generate an image volume approximately 100 mm per side in 3 seconds. The architecture is scalable over a limited range in both display size and computational power. The limitations on system scalability will be identified and solutions proposed.

We propose a generating method of Computer Generated Holographic Stereogram consisting of a set of Fresnel transformed 2D TV camera images. A reconstructed image of this method can be shown near by hologram, because this hologram is a Fresnel type. This method can display real objects without a conventional holographic system for getting holographic data. As the view angle changes with moving eye, 3D display can be obtained. This paper describes the principle and demonstrates 3D display using the presented method on the electric holography system.

A 3D video system utilized 3D Grating Image technology is described. The system is composed of a liquid crystal device and a grating array. The system can construct 3D images in real-time that are observed with parallax in observer's eyes. Although this is caused from diffractive effects of the grating, but is not the `holographic display'. In this paper, we describe the principal of this 3D video system and experimental results for 3D animation display.

The optimum sub-hologram dimension of composite Fresnel and Fourier transform holograms was found as a function of information reduction ratio. The total image blur in the reconstructed image from the composite holograms was calculated and measured experimentally. The test object used to this experiment was a plane sheet with strips of 5 different sizes drawn on it. In this strip object, the total image blur will be given as the resolution loss in the strips. The experimentally measured value of the total image blur matches reasonably with the calculated one for the case of the sub-hologram with optimum size.

Canonical minimal-pixel hologram geometries are presented in the context of a generalized image relay system. We illustrate that the number of pixels ultimately depends only on the physical parameters of the displayed image (the Smith-Lagrange optical invariant). Various choices of synthetic optical geometries lead to pixel aspect ratios that are found to be good matches to available display technologies. We explore geometries in which the spatial light modulator is imaged at either the image-plane or the viewer-plane, or astigmatically imaged to both at the same time. This increases the variety of candidate aspect ratios considerably, and brings us close to a workable match with foreseeable optical technologies that will make holographic video a practical reality.

A CAD system with electronic holography is expected to provide ideal designing environments to feel and touch truly 3D images directly. However, interactivity and real-time computation of holographic fringe patterns are the essential requirements to realize it. This paper presents two different types of 3D images creating system. One consists of a 3D pointing device and an electro-holography system with an acousto-optical modulator which was proposed by Prof. Benton in 1989. The other consists of a 3D pointing device and an electro-holography system with a liquid crystal device. We also propose an effective method not depending on the total number of points in the scene and apply it to the designing tool by only appending points in a electro-holography system with a 3D input device.

The holographic stereogram approach is used to reduce computational time of computer- generated hologram for 3D displays. It can be obtained by Fourier transforms of an array of 2D perspective images, and computational speed is quite faster than that of Fresnel hologram. However, the conventional holographic stereograms are made from an array of pure 2D perspective images, which do not have depth information. Therefore, the reconstructed 3D image has lower resolution than that of Fresnel hologram. In this paper, we have discussed the stereographic approach as an approximation of wavefront reconstruction, and propose `integral hologram' which can be defined as an improved or `coherent' stereogram. `Integral hologram' is calculated by a similar way to the holographic stereogram. However, the input data are obtained not from an array of 2D perspective images, but from 3D coordinates of the object. From numerical analysis, we demonstrate that the `integral hologram' has image resolution as high as Fresnel hologram, and can be computed as fast as the conventional holographic stereogram.

The OMEGA project (Brite-EuRam 5470) intends to solve the problems arising from the lack of real time dimensional control on steel structural mill facility products. The main objective of the project is to assess the feasibility of an on-line, advanced passive non-contact measuring system, controlling complex geometry parts in adverse environment, featuring a high level of reliability and accuracy on measurements, with low cost. Such a measuring system will be based on Conoscopic Holography as the basic technology to be applied. Conoscopic Holography avoids some of the problems of conventional holography, such as the necessity of ultra high stability, coherent (but monochromatic) illumination and ultra high resolution sampling techniques. Thus, it is possible to produce holograms using incoherent light with a typical fringe period compatible with the resolution of normal electronic imaging devices, such as CCD cameras. In the application developed under this project the conoscopic head will have to meet requirements never tried before regarding the adverse working conditions. The paper will summarize the main objectives of the OMEGA project, now in progress, a description of the technology applied and the results available from the lab testing work when the paper is submitted.

Projection system based on Liquid-Crystal Displays (LCDs) offer new opportunities to display high definition and large size TV images. In order to increase LCD projectors performances, in particular the brightness and optical efficiency, we propose to introduce Holographic Optical Elements (HOEs) in the optical architecture of the projector. Due to their spectral bandpasses, phase volume HOEs are very well suited to the design of dichroic components. These components are, for example, either dichroic mirrors with specific polarization and 16/9 anamorphic properties in a 3-LCD architecture, or dichroic micro-lenses for selective focusing in a single-LCD architecture. First, this paper analyzes the conditions that must be fulfilled by the HOEs in LCD projection systems. It concerns spectral and angular bandpass and colorimetric properties in the presence of white light illumination. Then, examples of phase volume HOEs (mirrors and lenses) satisfying those conditions are presented. A complete colorimetric analysis is achieved with red, green and blue holographic lens characteristics in a single-LCD architecture. Also an evaluation of the gain of luminous flux obtained by using these components in place of classical color filters is presented. Our HOEs have been recorded in a photopolymer from DuPont corporation.

Until recently, the power of volume holography has gone unused by spectroscopists. This was due partly to the difficulty of making stable, high-performance volume holographic optical elements, and partly to poor communication between the holography and spectroscopy communities. We have applied volume holography technology developed for military uses to the needs of spectroscopists. The resulting holographic components and holographic imaging spectrograph have been combined into a new instrument. This Raman spectrometer is fiber- optically coupled specifically for process monitoring and control applications.

Until the appearance of the color copier, security features were optically invariable devices (OIDs). Nowadays, deceptive color copies of OIDs can be made. Optical variability however, is unattainable by the color copier. Optically variable devices (OVDs) are either based on specular reflection (metallic foils), diffraction (holograms, etc.) or interference (thin films, Bragg structures, etc.). A classification of OIDs and OVDs is presented. It is proposed that the degree of microstructural order of an optical feature is an approximate measure of its practical value for document security.

A holographic interferometric microscope is presented, which combines conjugate reconstruction and two-reference beam method to apply the static evaluation method with 3 illumination directions. In this way the determination of every component of small displacements over objects which are smaller than a millimeter is possible. A solder bond and a surface mounted resistor were used to test the performance of the proposed hologram- microscopic arrangement. The thermal deformations under operation conditions were investigated. The orthogonal displacement components were calculated from the experimental results and compared with the expected deformation behavior.

We are researching 3D display using Liquid Crystal Devices (LCDs) as spatial light modulators to control wavefront for reconstructed 3D holographic image. We have tried to expand the image size and viewing zone, especially on vertical direction. The image size depends on the size of LCD pixel, and the viewing zone depends on the number of LCD pixels. So we use half mirror to set up three-fine pixel LCDs continuously in horizontal direction. In our display of first step, we can see 14 mm in width of image size, under +/- 1.2 degree(s) in angle of horizontal viewing zone. But in vertical direction, since the number of LCD pixels are limited, the reconstructed image size and viewing zone become small in full- parallax off-axis holography. So we discard the vertical parallax, which makes the necessity for number of LCD pixels to diffract the wavefront too large. We use cylindrical lens to expand the vertical image size and adjust the image plane, under the condition of discarding the vertical parallax. And we set lenticular sheet on the image plane to get wide vertical viewing zone.

A new experimental technique has been devised to measure residual stresses in ductile materials with a combination of laser speckle pattern interferometry and spot heating. The speckle pattern interferometer measures in-plane deformations while the heating provides for very localized stress relief. The residual stresses are determined by the amount of strain that is measured subsequent to the heating and cool-down of the region being interrogated. A simple lumped parameter model is presented to provide a description of the method. This description is followed by presentation of the results of finite element analyses and experimental results with uniaxial test specimens. Excellent agreement between the experiments and the computer analyses were obtained.

Hopfield neural nets are used to optimized point-oriented binary computer-generated holograms (CGH). The results are comparable to other iterative methods and may require shorter computation times. In this process, the generation of the CGH by FFT, binarization, and IFFT is viewed as a `black box' with inputs and outputs consisting of 512² arrays containing an object of size 64². The neural-network optimization feeds back the Fourier transform of the reconstruction error to update the neuron states, which correspond to the samples of the continuous hologram. To reduce the error of the reconstruction, the input is allowed to deviate from the original array in different specified ways. For example, a previously reported approach using Projection Onto Constraint Sets varied only the region of the input array outside of the object, while we allow the entire array to be modified, thus providing more freedom in the optimization. The method may be applied either to magnitude- only or phase-only holograms. We also report on a modification of the parallel updating function. Different optimization options are compared. Use of a practical printing model requires optimization under assumed constraints to test the convergence properties of the algorithm.

Error diffusion is a useful tool for quantizing N-dimensional data. For complex-valued amplitudes (N equals 2), error diffusion has been used to improve reconstruction of hologram of objects with added random phase. In this paper, the stability of holograms obtained by conventional independent quantization and error-diffused quantization are tested under varying conditions of quantization and for several types and sizes of images. The restoration of missing high-frequency components due to feedback of the error improves the reconstruction of objects even without a random phase. The results are improved further by coupling error diffusion with a nonuniform quantization.

When aberrations are present the principal maximum of the axial irradiance does not lie at the Gaussian image point but at an axial point closer to it. In general there may be more than one diffraction focus and a criteria is needed for the election of the best image point in the sense of minimal aberrations, we have proposed an entropy function as merit function for study the best image plane. In this paper we present an experimental procedure for the measure of the entropy of an different imaging planes for holographic optical elements. The point spread function of the holographic lens is recorded with a CCD camera for different imaging planes, taking as origin the Gaussian image plane. The CCD camera is controlled with a computer, and axial displacements of 1 micrometers are possible. With a computer program, the Point Spread Functions obtained are normalized to the total intensity of the plane, and then we have a probability distribution associated to every imaging plane. Using the definition of entropy, we numerically calculate the value of this magnitude. We represent the entropy as a function of distance from the Gaussian image plane and compare the results with theoretical predictions. A good agreement between theory and experience is found, so the concept of entropy could be used for finding the best image plane in holographic optical elements.

The multi-passage optical fiber faceplate, which has been successfully designed and made by us can exert direct effect on separating colors and encoding a transparent color film, so the encoded images will be sampled and compressed at the output end of the faceplate. Their coherent encoding images will be available when the three primary color images are written into a liquid crystal light valve (LCLV) and a laser beam is directed to read out these images through a polarizing beam splitter. Then, the read-out images will be transformed by a Fourier lens and recorded by a black-and-white film. Especially when the stored image is a color scene, preprocessing can be eliminated from the equipment proposed in this paper only by introducing a color CCD camera or an imaging system, coupled to the optical fiber faceplate's input end. The original color image can be also retrieved by the faceplate used in the opposite direction. The first-order diffractive image obtained from stored medium is written into the LCLV and a white light is directed to read out this image through a polarizing beam splitter, the read-out image should be accurately projected at the output end of the faceplate. These encoded images are colored by three primary color filters and transmitted to the input end of the faceplate. Thus, the stored original color image is retrieved.

The results on the experiments on recording reference-free selectograms that reconstruct 3D images of objects are given. The selectograms were recorded by splitting the radiation of the object into two identical components with the help of diffraction gratings placed in front of a light-sensitive layer. The recording was performed on thin-layered inclined light-sensitive plates by using the method of pseudodeep holograms. The possibilities of recording reference- free selectograms of such a kind by a coherent radiation as well as by the radiation with a restricted spatial coherence were studied. In the case for which the selectogram was recorded by a coherent radiation, the radiation scattered by the object was split into two components by a diffraction grating placed in front of an inclined light-sensitive plate. The selectograms recorded in such a way reconstructed the volume images of objects whose resolution was sufficient for visual perception. For recording in an incoherent radiation an interferometer was suggested that was composed of two diffraction gratings which shifts the plane of the zero path difference of interfering beams into the center of the inclined photographic plate. The restriction of the coherence of the beam illuminating the object was performed by moving a diffusor that was used for illuminating the object-transparency. The selectogram recorded in such a way reconstructed the image being in a form of a luminous horizontal stripe corresponding to one of the horizontal cross-sections of the object being recorded. The experiment on the multiple recording of selectograms on one photographic plate at the successive displacement of the interferometer along the optical axis of the system has been carried out. In this case, the reconstructed image represented a system of horizontal luminous stripes each of them representing one of the lines of the image of the recorded object.

Suggested is a new method to obtain a holograms, based on the use of optically-active-media properties. The light wave scattered by each object point is linearly polarized and transmitted through an optically active medium. The more is the spreading angle of the given wave area, the more becomes its way through the optically active media and consequently the more becomes the rotation angle for its polarization plane. Further the light wave passes through a polarizator. Behind the polarizator a Gabor-zone-lens pattern is formed. Each circle, dark or light is a geometrical place for points of beams with equal angle of polarization plane rotation. Superposition of the Gabor zone lens from each object point is the hologram. Application of this method permits to obtain the holograms without interferometry. So the suggested method allows the use of noncoherent waves for registration of the holograms.

In this paper, a holographic off-axis 4F optic system is used to record 3D hologram of spray field. The advantage of recording spray field using this system is described. And image processing of this particle field hologram is achieved. We also describe several algorithms--the morphology algorithm which is fit for automatic analysis of particle hologram, partial meaning and camber fit threshold method, a method of particle pairs judgment based on coherence value, a method of plotting the over-lay particle pairs based on the edge shapes. In the end, the processing result of a double-exposed particle field hologram is given out including statistical figures of the size, quantity and velocity of particles.

The development and investigations of large-formate (8-inch) real-time photothermoplastic (PTP) camera are carried out. The PTP camera is applied for operative recording of 3D- images by means of compound and digital holography and visualization of these holograms as 3D-static images. The optimization of the recording regimes is fulfilled with use the model of the relief-phase PTP images thermodevelopment, proposed by authors. According with that model, the achievement of maximal value of deformation (diffraction efficiency) is based on the opportunity in increasing of charge contrast of electrostatic latent image formed early by the moment of the viscosity decreasing during the thermodevelopment process. It is achieved by means of the control of the thermodevelopment regime. Also, the opportunities of the increase of the camera size (to 14 inch), of the rising of photosensitivity value and the enlarging of its spectral range, of the creation of Benton holograms and of the increasing of the speed of response to 25 Hz are discussed.

We demonstrate transmissive holographic stars based on multiple-beam planar configuration and multiple-exposure with Bragg degeneracy effect fabricated in Du Pont photopolymers HRF-610 with He-Ne laser light. With the latter approach the required number of gratings is reduced significantly. The stars can operate in a relatively large window of replay wavelengths only by adjusting the Bragg angles. Experimental results are presented.

It is a general problem in the electron holography that the long-range fields always affect the phase of the reference wave. The electromagnetic field of the specimen, which always spreads outside the specimen, not only is strictly limited within the region crossed by the object wave, but also extends as far as the region crossed by the reference wave, so the phase of the reference wave becomes unknown as well as that of the object wave. The perturbation of the reference wave has far-reaching consequences that a reliable reconstruction of the original object wave is presented since an optical replica of the perturbed reference wave is not available. In this paper, we proposed a method to eliminate the influence of the perturbed reference wave. Based on phases' relationship between the reference wave and the object wave, with digital reconstruction and data process, we can extract the phase of object wave from the phase difference between the object wave and the perturbed wave, which is always obtained in normal reconstruction. An example of one-dimension electromagnetic fields is given to verify this method.