A pseudodeep hologram is a thin, inclined hologram on which a one-dimensional line object is recorded by a sagittal beam system; at reconstruction, the object is read within the limits of the narrow line which corresponds to it. High angular and spectral selectivities have been obtained by these means. Attention is presently given to the possibility of recording and associative reading, in view of results from experiments in which the associative reading of a pseudodeep hologram was performed on the bases of fragments of the object in question by a simple graphic-reconstruction method. Components of images caused by the recording medium's nonlinearities are noted.

Single-frequensy He-Ne laser for holography is described. The increased radiation power and efficient coherent wavelength are the result of usage of 11-shaped resonator with selective mirrors and intacavity Fabry-Perot interferometr. 1 .

A holographic method was used for investigation of very slow dif fusion of anthracene compounds in glassy polymers. The results show that properties of large organic molecules diffusion differ greatly from those known for small molecules. The diffusion of substituted anthracenes determines mainly the stability of holograms registered in volume phase medium Reoxan. I .

Calculation of holographic technique economic e1ficiency to determine efficiency of the taken decision compared with other possible variants is to reveal relative economic efficiency of the newly created construction in comparison with advanced science and technology achievements.

A new method of holographic recording in the form of a thin laser beam which moves consecutively parallel to itself is being discussed which gives the scanning of all the space which is being holographed (object+hologram). Such a recording has been experimentally carried out in a single-beam scheme after the method of reflective holography and the technique of receiving large- sized holograms of scenes of a sufficiently large size has been improved. The production of higheffective reflective holograms on bihromate gelatine has been discussed a new technology of heat treatment has been proposed and an experimental check has been carried out. Gabor studying the ways which help us to improve the resolving power of an electron microscope created a new holographic method of an optical image. In particular while illuminating an object by a coherent light wave (the greatest part of'' the wave Is supposed to penetrate the object without disturbance) the diffraction image formed as a result of the secondary wave interference which appear in the presence of an object with a strong reference wave is recorded on a photographic plate. The reference wave transforms phase differences into intensity differences that is the phase turns out to be encoded in the quantity which is recorded on a photographic plate. In 1962W 1964 E. Leit and U. Upatnieks substantially improved Gabor''s method by using2 a laser and the off-axis recording scheme.

The development and putting into production ultra-fine grain silver halide photographic materials for holography on a flexible film base were started in the USSR more than twenty years ago when the holographic method of image registration was first employed in science and technology. Photographic films fl-Th2 and fl-Th.T designed for image registration by means of the converging beam scheme were widely used in holography till recently.

The formulae for calculation of third order monochromatic aberrations coefficients of an off-axis element with carry out pupil are given. The conditions of a simultaneous compensation of coma, astigmatism and field curvature of an off-axis holographic lens /HL/ with carry out pupil are discussed.

In the given work the procedure of receiving highly effecyive spectrally nonselective reflection holograms is described. The procedure is based on taking into consideration the dependence of the depth of recording medium. The curves of dependence of diffraction efficiency on the wavelength of reconstructed by selective and nonselective holograms on several wavelengths have also been received. The work1 for the first time showed the possibility of creating spectrally nonselective holographic mirrors and described the procedure of their production on the layers of dichromated gelatin (DG). In this case a substantially important condition of nonselectivity is a strong absorption of actinic radiation in the original emulsion layer by which the damped character of the summary field according to thickness in conditioned. In the process of developing the exposed layers there is a transformation of the structure with a constant spatial frequency into the structure having a definite gradient of this structure along the thickness. The value of the absorption coefficient of the original emulsion layer necessary for achieving the effect of nonselectivity was found experimentally ( 73 X 406 nm). 2 In the given work the same considerations were for receiving Denisyuk''s spectrally nonse. . . lective reflection holo- grams on DG. The summary field in the depth of strongly absorbing hologram layer in paraxial approximation has the form of: I( I0e I(x 2 I I(x I reference wave intensity r (x

The possibility of polarization holographic recording of a standing wave in the case when the same (right or left) circularly polarized plane coherent light waves propagate in opposite directions has been discussed. The propagation of a normally incident circularly polarized wave along the helical structure formed in a photoanisotropic medium has been discussed by means of the Jones matrix method. The selective reflection of the circularly polarized component of mcident light from such a reflectance hologram is possible. When summing up two coherent light waves with different polarization states the summary field is characterized by a definite distribution both the intensity and resulting polarization. The use of photoanisotrophic media enables us to make a polarization-holographic recording of the summary field and to reconstruct polarization state of the object wave from the obtained hologram. 2 3 If we use two beams with orthogonal right and left circular polarization '' which spread at a small angle with each other the projected picture of the summary fields in the hologram plane has the form of a periodic structure corresponding to a linear polarization with orientation rotation of the resulting vector from O to 180 within the period. The absence of intensity modulation on the hologram plane leads to a uniform distribution of the values of light-induced anisotropy. Th use of photoanisotropic media on the basis of mordant azo dyes intrc1uced into gelatin matrix

The three-dimensional polarization hologram which is formed by adding mutually orthogonal circularly polarized reference and object waves is discussed. Photoanisotropic materials are used for polarization hologram recording. The theoretical expression for an image formed by a polarization hologram has been obtained. For the recording medium with the given characteristics, the thickness with which all the energy of the reconstruction beam is pumped into a reconstructed image has been determined. It is noticed that the three-dimensional polarization hologram allows image reconstruction to be accomplished with an extremely high diffraction efficiency.

In the paper there are presented results of study of the Hercshel effect (HE) for a number of s I lver hal ide ho 1 ographic photomateri al s such as BPI1 J1014-2Y. 11014-3 14A3 under exposure by act iri c and nonact I ni c 1 aser radi at Ion (NAR) of various durations (10 10 10 s). The observed in experiment reciprocity law failure according to the HE is specified by different contributions of electron and hole components of the HE. In accordance with such a not ion the centers of 1 atent I mage C LI ) can be damaged by two ways : 1) absorption of NAR by LI center accompanied by transition of electron into conduction band with the following recombination and 2) release under the action of NAR of holes from surface traps into valence band and their recombination with electrons trapped in the LI centeis. It is shown that Intensification of the HE under the action of NAR of 10 s duration depends in the main on the hole component. Results obtained in studies of the HE for photomaterials with different types of chemical and spectral sensitization as well as after their treatment with chemical reagents specifying the kinetics of free charge carriers on surface of emulsion microcrystals permit to refine the notion about their part in processes of LI formation. 1.

Transmissi on rel i efphase hol ograms made on the CK1 7 type photor-esist and recorded in a codirected asymmetrical scheme are studied. The diffraction efficiency of the holograms obtained is shown to exceed 50 for fi rst order of di ffracti on. A substanti al difference i n angul ar dependences of di. ffract i on effi ci ency i s shown to exi st f or plus and minus first orders of diffraction. 1 . INTRODUCTI ON At present there is a strong trend towards development of methods of making effective transmission reliefphase holograms'' . This is due to the fact that these holograms permit realization of high diffraction efficiency CDE) comparable to that of deep holograms the merit of these holograms is the possibility t. widely reproduce then by mechani cal stampi ng3. The most important parameter determining the possibility to realize high DE of transmission relief phase CTRP) holograms is known to be a X/d ratio value4 where Xis the wavelength o radiation of illuminating source dis the period of relief structure of a hologram. For example if the X/d value is less than 0. 3 then the maxi mal DE val ue whi ch can be real i zed for TRP hol ograms does not exceed 40. If the /d value is approximately unity then the t heor et i c al DE val ue c

This report concerns thick phase polymer recording media Reoxan and holographically manufactured optical elements recorded in them both media and elements being developed in our laboratory. Reoxan in traditional realization is realtime medium and dynamic effects of recording take place. That is why reflective holograms (base of narrowband wavelength selective elements) of highefficiency can''t be recorded. We have developed a new recorAding glassy polymer compo sition acting in a " quasidynamic" regime (lowefficiency hologram recording with further selfenhancement). Such a medium gives one an opportunity to obtain both reflective and transinittive hD1ograr of very high diffraction efficiency close to theoretical limit. Parame ters of higheffective holographic spectral selectors recorded as reflective holograms in this medium are also considered in ths report. I . INTRODUCTION. HOLOGRAPHIC SELECTORS The development of coherent optical methods of information transmission storage and transformation is determined by element base level. Specterselective elements play an important role in the field of information treatment. The traditional representatives of such elements are multylayer interference and interference pola rization filters diffraction gratings etc. Higheffective narrowband selectors based or reflective holograms in 3dimension phase recording materials'' can be serios competitors for such devices due to unique proporties of reflective holograms such as high spectral and angular selectivity relatively simple fa5ricticn high efficiency. The earliest wide experimental investigation of thick phase reflective holograms was carried out by dr. Sukhanov arid co-workers

Holographic storage and reconstruction of nonstationary waves can be accomplished in spectrally nonselective media through the use of a three-dimensional recording medium, as well as by the two- and three-dimensional holography of waves that are produced via spectral decomposition of light pulses. Attention is given to the superfast scanning of light beams and the possibility of picosec-femtosec chronophotography. It is shown that the interactions of spectrally resolved ultrashort wave packets with monochromatic waves allows the formation of holographic analogs of moving optical elements, while using neither direct nor indirect macroscopic shifts of optical hardware.

The problem of the amplification of low intensity radiation pulses can be solved by the utilization of the optical amplifier based on the dynamic holograms (DH), as one of the methods. This permits to concentrate almost all the radiation from the illuminated object in the solid angle required for monitoring, thus, providing the decrease of the requirements to the sensitivity of the monitoring equipment, that is the photomaterials on the holographing of the diffuse reflecting objects, in particular. It is expedient to record the DH in the media with thermal nonlinearity, because in tnis case the effective transformation of the equal frequency beams on the small thicknesses ( less then 1 cm ) of the nonlinear medium under practicallj any crosz-section dimension :an be carried out, and the wide range of adjusting C 10+ i0s ) of the temporal scales of the Dii recording and reconstruction is possible just by c.angirg of the crossing angles between the incident beams.esides, under th certatr conditions the thermal DH can provide the image amplification with the increasing of their contrast.The investigation of the effectiie unsteady transformation of the plane waves has been carried out earlier, in this paper the results of the investigation of nstady mgification and phase abbezations (PA) of the difluse light beams durng their interaction in the thermal DH, re presented.

Due to the wavelength difference between the insonifying object wave and the reconstructing light wave ultrasonic holography as a three-dimensional imaging technique has little if any practical value. By introducing the concept of " empty US hologram" and " complete US hologram" and combining it with moire technique attempts are made to extract nonpicture-type information from US holograms. 1 .

The results of the investigation of a pulsed hololaser or recording of monochrome (sized 600x400 mm ) and two-color (size 300x400 mm ) holograms and topograms (included living beings) are presented. The holosystem is based on Nd phosphate glass laser with frequency doubling (A nm) and Raman conversion in compressed hydrogen (A nm). 1.

The photophysical mechanism of the real-time hologram recording for the new photopolymer composite is presented. The new hologram re cording mode for the material - the " dark" amplification of a prima-'' ry weak holograms resulted from the postpolymerization is disco vered and investigated. I .

The process of manufacturing the display holograms on photographic plates rWr-03 is based on the interference copying of the reflection holograms from the reflection original /1/ followed by chemical treatment close to that recommended by the manufacturer of the photographic plates /2/. However, there is a number of salient features characteristic of the group production of the holograms. The aim of production is the serial manufacture of the ready for use articles-holographic elements designed for completing the goods for cultural and household needs or special-purpose goods as the main element or self-contained article. The holographic element is the hologram of rectangular, round, oval or other shape reconstructing the qualitative three-dimensional image and having a reliable protection of the photographic layer from external actions. It is implemented by introducing to the manufacturing process (in addition to the main operations of the exposure and chemical treatment of the holograms) the operations of moulding the holographic element, hermetic sealing of the photographic layer and applying the decorative or contrast coating. The paper discusses the problems of the manufacturing process, i.e. the optimization of the optical scheme and exposure procedure, selection of the modes of chemical treatment of the holograms, employment of the group tooling, meeting the requirements for the safety of the holographic elements, requirements for the production areas as well as the problems of mechanization and automation of the processes. In addition to this, the problems of organization of the production and sales of the holographic elements are briefly considered.

The present paper is intended for assessing the market of commodities based on display holography for the last years and prospects of its further expansion as well as for finding our own place in this market, taking into account our features and achievements. The review of the commercial activities was mainly made from the materials published in the specialized journals "Holosphere" and "Holography News" in 1985-1988.

The search for more perfect ways of transmitting the knowledge to the pupils so as to enhance the effectiveness of teaching and communicating more precise information on the studied subject is one of the natural phenomena characterizing the pedagogical process at present. This means the perfection of the methods of teaching, organization of the teaching process and use of the latest means of education, the holographic means being included. Since holography is finding ever increasing use in the spheres of education /1, 2/, the expediency of developing these or those holographic means of education (HME) as a way to solve didactic problems becomes extremely urgent.

Holography is mainly applied for recording and reconstructing the wave field giving information about the object under study that is mostly a three''-dimensional one. In the present paper the holograms are supposed to be used for testing colorimeters employed in various branches of the national economyl. In this case a reference standard is a reflection hologram of diffuse surface. The spectral distribution J1(X) of its reconstructed light flux is certified by a high precision spectrophotometer and converted into colour coordinates. Carried out in the paper is the calculation of the hologram reconst ruction conditions and given are the results of the experimental re cording of holograms and reconstruction thereof. 1. CALCULATION OF HOLOGRAM RECONSTRUCTION CONDITIONS When working out the practical schemes of recording and reconst ructing holographic colour specimens it is essential to know how the wavelength of the reconstructed radiation A1 is changed with the change of the angle of incidence ac 0f the reconstructing beam of white light. To calculate X let us use the Bragg equation2: XI n2d Sin c (1) where d period of interference pattern c - the angle between direction of reconstructing beam in medium and plane of interference pattern n - refractive index of medium. Using the beam plotting when recording and reconstruction of the hologram are carried out (Fig. l) we shall obtain the expression for A1 2nA A - R I

The conditions to obtain the maximum diffraction efficiency /DE! for different types of 3-D holograms are discussed. Holographic methods to measure recording media parameters that influence DE are described. The examples of measuring of these parameters by the holographic means are given.

Geometry analysis of pseudocolor holograms was carried out. Color shift of reconstructed light emission and relative image brightness dependance on emulsion expander content was defined.

The methods are described to obtain monochromatic and color holographic portraits, being reduced in laser and white light with the use of pulsed lasers in red and green spectral regions.

A new nethod of stabilizing interference field using the two-wave mixing of the interfering beams at the reflection hologran being recording is described. The results of theoretical analysis of self-diffraction signal for absorption and phase gratings are presented. The simal was used for hologram recording in a dichrcnted gelatin and photorefractive crystal Bi12TiO20 to denonstrate advantage of operation a negative feedback system of holografic setup. 1. An active stabilisation of interference field (IF) is used for hologran recording . It consist in the autcntic coripensation of randan phase difference of reference and object waves by phase corrector and feedback loop. For the . obtaining of siial correction usually additional optical elennts is insert in holographic setup for the forming of the auxiliary interference pattern with low spatial frequency. Instability of this elennts leads to appearance of the false correction signal. For the renoval of this defect it was suggested1'' 2 to use t-beani recording-reathng nethod (or self-diffraction nthod) for obtaining feedback siial 1*it applicability of the nthod was limited by recording of the trantssion phase holograms. In this paper the results of self-diffraction signal analysis for reflection hologram recording using register ndiun with absorption and phase nature of prinry holographic structure (EHS) is discussed. Al so the ______ )I [1101 0 x1 Fig. i. Waves P0 and S0 interfere an interference pattern and a voliii grating in the recording naterial of

Kinetics of fast electronic stages of photolysis of silver halide microcrystals (MC) with characteristic dimensions 30 -- 50 run is investigated It is determined that influence. of UV or visible radiation ultrashort pulses results during some pictoseconds in appearance of nonetationary state of MC sensible to lB radiation . This nonstat. ionary state relaxes in some hundreds picoseconds . On the tsis of experimental results analysis it was concluded low ff1C:1ncy (. fei prceiits ) of use f. r Iatnt image formation. I - THTP0DUCTI(:)N Research of kinetics and efficiency of fast stages of iat. nt image formation in MC of silver halides holographic photmu1sions seems urgent to know the features. of silver halides photomatrials responce for pulsed exposition and ieculiarities of such materials application in pulsed holography . Picccorid spectroscopy methods seem purspctive becouse they ensure sufficient t1 me resolution and possibility of MC exitation by time separated pulses of actinic and nonactinic radiation. 2. EXP1RIMENT In the experinents we use lasers with nde-lcsking radiating trains of picosecond or single picosecond pulses varions silver halides emul. si'':sns with MC dimensions 30 - So rim were used . We studied otographic resxnse to the influence of single pulses or pair of pulses with different wavelengths and various delays also real time prcoesses connected with radiative ( luminscence) and nonradiative (pulsed optoacoustic effect) electronic transitions in MC were studied. Basic scheme

The article is devoted to the inverstigation of the dependence between hologram phase shift quantity and its optical density in wide interval of exposures and kinds of developments. The characteristic curves arid phaseexposure characteristics have the similar appearance the initial parts of the curves are straight lines then it can be seen the slowdown of the growth of both curves. The slope of linear parts of the curves depends upon the development time nature of developer the type of photoemulsion and the hologram recording space frequences. The investigation of photomaterial optical characteristics which cause the different parametries of holograms is one of the actual questions conserned with evaluation of holographic image qualityt''2''3''4. The determinational methods of these characteristics were proposed in it was payed attention to the linear character of the dependence of bleached holograms phase shift A4 upon its optical density AD before bleaching3''61 K-AD(AE) () where AE the change of exposure which causes the change of optical density AD K - constant which depends only upon the type of used bleaching agent. The practical value of this equation is explained by its simplicity. However the interval of exposures in which this statement is correct was not distinct before the present time. Usually the quantity AD is calculated on the low 158 / SPIE Vol. 1238 Three-Dimensional Holography: Science Culture Education (1989)

A new principle of reflection silverhalide gelatin (SHG) holograms generation is presented. The formation mechanism of the micro-cavity structure of holographic gratings is investigated. Based on the principle discussed here three methods of processing are suggested for making highly efficient SHG reflection holograms in the blue the green and the red regions of spectra with properties similar to those of conventional dichromated gelatin (DCG) holograms. 2. SHG HOLOGRAMS AND ANALYSIS OF THE PRINCIPAL OF THEIR FABRICATION Optical properties of DCG holograms and high light sensitivity of silver halide materials in the whole visible spectrum range can be combined in SHG holograms in which light field interference pattern recording is realized on silver halide grains while the light diffraction during the reconstruction takes place on a gelatin layer similar to DCG layer having a refractive index modulation. There exist a number of methods for transforming a ''silver'' structure into refracted index modulation structure. They are based on selective hardening of silver-halide layer gelatin. According to Pennington et. al. [1] selective hardening takes place as a result of the effect of laser or UV light on a silver halide developed fixed bleached and ammonium dichromate sensitized. A gelatin in isophase grating planes is hardened to a less degree that between planes due to high adsorption of a halide silver. After the removal of halide silver from the layer during the next fixing process

Three schemes of realization of micro-cavity method of processing silver halide photomaterials for silver-halide gelatin holograms (SHG) generation are proposed. Factors affecting diffraction efficiency replay wavelength shift and selectivity are discussed. 2. EXPERIMENTAL RESULTS In the previous paper on this issue the principle of SHG hologram formation based on a difference of speed hardening of gelatin mass in a photolayer and in a thin cover of gelatin absorbed on silver or silver halide grains was formulated. The investigation of " swelling" factor for layers both containing and not containing solid grains verified the difference in the hardening degree of these layers and demonstrated a possibility of using this phenomenon for the generation of SHG holograms. As a result we proposed three methods of transforming the structure of distribution of solid particles of a layer into the structure of micro-cavity distribution. Processing procedures realizing the micro-cavity (MC) methods are presented in Fig. l. As seen in Fig. l the differentiating feature of each method is the type of grain in a layer during its hardening. In the course of realization of methods MC-l MC-2 and MC-3 a layer to be hardened contains metallic developed silver rehalogenated silver and silver resulting after reversal bleaching of developed silver respectively. The common feature of all methods is dehydration procedure which results in producing micro cavities in the places of removed silver or silver salt grains.

High sensitivity values of dichromated gelatin (DCC) layers to the exposure of cw or pulsed radiation are achieved by DcC layer characteristics optimization conducted on all stages of hologram fabrication. The results both for voluii-phase holograms and relief-phase holograms are obtained I .

The distribution of holograi structhre period and aodulation aaplitude of the gelatin refractive index in the layer thickness under different developent conditions s studied on the base of microcuts of holographic optical eIeents on a dichroaate gelatin layer. It was shown tMt development with swelling at p11:4. 7 provides a uniform hclogras structure throughout the recording layer thickness. 2JJflj Analysis of spectral characteristics of election holographic optical eieents (E) on a dichronate geatin 1) layer by the coupled waves or flake media theories suggests a substantially sxal1er rated thickness of hologram structure as compared to tof recording layer. When diffraction efficiency (DEl values account for 90 and above a rated thickness of bolograas is generally associated with a high value of oduiation amplitude of gelatin refractive index n1of the hologram in this case the contribution of deep layers of reflection hologram structure into the DE value appears to be minor. Lack of fire data on the n1distribution and period T of hologram structure in gelatin layer haapers working out HO iving optimal optical characteristics such as high BE prescribed band of spectral and angular selectiviti and having a low lev?l of diffused light. The paper deals with the experimental procedure aad results of the above parameters of hologram strctre wich allow cptiization of the process of E paraaeters close to theoretical ones. 3 - EXPERBIENTAL BRQCEDURE Studes were performed 2n 10

Optical spectrometry Xray diffraction and molecular light sea ttering were used to investigate the formation of holographic structure of a hologram mirx''or in a gelatin layer sensitized with ammo nium dichromate. It is shown that the intheed phase contrast of the holographic structure is formed due to rnicrophase separation o the system watergelatin-isopropanol into two polymerenrihed or sol ventenriched phases further polymer glass transition which results in the interruption of phase development and micropore formation caused by the removal of a solvent from the recording medium. Pore size distribution is determined by the density of crosslinks (mi tial and formed as a result of photochemical and dark reactions) in the bulk of the recording medium. t.

The paper summarizes the results of investigations performed to obtain deep 3-D holograms with 102 i0 mkm physical thickness allowing the postexposure amplification and the a posteriori changing of the grating parameters. This aim has been achieved by developing heterogeneous systems on the basis of porous glass with light-sensitive compositions introduced into it. 1. INTRODUCTION. LIGHT-SENSITIVE MEDIA FOR 3-D HOLOGRAMS RECORDING. The 3-D holograms have many useful properties: very high diffraction efficiency angular and spectral selectivity but low level of noise. It shoud be noted that in this case deep 3-D holograms are dealt with whose physical thickness is as high as 102 -i mkm. Such hologram recording is usually done using homogeneous light-sensitive media for example dyed acid-halide and electrooptical crystals photochrome glass photostructurized polimer compositions and so on. The nature of photophisical and photochemical processes responsible for the light sensitivity of these materials exclude the possibility of post-exposure treatment. This does not allow to enhance the recorded holograms and considerably hampers their fixing or makes it practically impossible. The object of our work is to create the media which are quite suitable for two-stage processes of the deep hologram formation with post-exposure processing. Such material must satisfy the following requirements: a)they must have high permeability for the developing substances in order to make the development duration suitable for practical applications b)they must be shrinkproof to prevent deformation of the

An analysis of Focar-S a new material for 3-D holograms recording is carried out. The new material comprises a heterogeneous medium based on porous glass and silver halide as a light sensitive substratum. There are some characteristics of obtained holograms for both non-developed and developed samples. INTRODUCTION. FOCAR-S -MEDIUM FOR 3-D HOLOGRAMS RECORDING Focar-S volume medium comprises a heterogeneous system which is composed of porous quartzlike frame (porous glas) on the walls of inner cavities of which stiffphase cover of silver halide subfine-dispersed suspension in gelatin has been formed. The inner cavities which are not filled with light sensitive substratum form the net of open4hrough capillaries providing a possibility of medium post-exposure processing. It is the possibility of post-exposure processing largely reinforcing a latent image that results in high sensitivity of a silver halide photographical materials as compared to other light sensitive stuffs. However when recording 3-D holograms on homogeneous media of nearly 1 mm thick these two-stage processes could not find application owing at least to two reasons. 1. The restricted permeability of light sensitive material for developing substance and for soluble reaction products has to result in inhibition of development and to disastrous growth of its duration up to the value which is unsuitable for practical application. 2. Swelling of light sensitive medium in developing solution and subsequent non-uniform shrinking of it while the sample is being dried results

There were examined mechanisms of arsenic sulphide films dissolution In water and spirit solutions of alkalis and in protonic and aprotonic solutions of aliphatic amines as well. Optimum conditions for the arsenic sulphide films processing without formation of a sediment and ratio of dissolution velosity of exposed and as-deposited parts of film less then of thousand units were found. 1 . INTIODUCTION It is widely known that holografic gratings (HG) have many advantages over engineruled gratings: they are free from " ghosts" have a lower level of scattered light it is possible to obtain gratings with frequency beyond 3000 1/mm The usial technique of HG manufacturing uses organic photoresists. The photoresists based on the low-molecular phenol formaldehyde resists with positive type of development are a most common choice. It is known that these resists do not dissolve in water but does dissolve in alkaline solutions The dissolution proceeds by molecular fragments each consisting of 7-10 phenolic cycles2through the stage of swelling which leads to a marked ruoghness of the etched surface and the distortions of the relief profile when the value of resolutions is beyond 3000 1/mm. It is indicated in Fig. 1 obtained with scanfling tunnel microscope. The resolution of the relief shown in the picture equals 3600 1/mm. It can be seen that at such values of resolution the obtained relief is distorted thus implying that the use of

Production of reflection relief holograms with asymmetric groove shape by two different. optical schemes is investigated. First optical scheme which was used is counterdirected. Second optical scheme is rionsymmetr-ic codirected. The holograms are made on photoresist CK17 type. It is shown that if spatial frequency of obtained holograms is corit. ant the hol ogram recorded i n a counter di rected scheme had experimental value of blaze wavelength about 220230 nm as calculated val ue of wavel ength was about 280 nm. The hol ograms recorded i n a codirected asymmetric scheme had experimental value of blaze wavel ength about 660-700 nm though the cal cul ated val ue was about 1560 rim. Diffraction efficiency of obtained holograms exceeded the value of 7O for natural light in both cases. 1 . INTRODUCTI ON The rel i ef hol ogr ams are usual 1 y made i n a photosensi ti ye phase type material with a two beam interference system. Interference fri nges have si riusoi dal i ntensi ty di stri huti on but the groove shape is not always sinusoidal being changeable with exposure and devel opment condi t i ons . But unti 1 the opti cal scheme used for obtaining holograms is symmetric the groove is also symmetric after the development. In 1Q62 Deriisjuk1 suggested method of obtaining holograms with asymmetric groove shape when the nodal planes

The results of three-layer colour holographic material producing were described under laboratory conditions. This material is preliminary studied for the registration of transmission colour holograms.

The unconventional nthod of hologram recording1 in contrary beams with sirailtaneous usage of all spectral caponents of a incoherent source with a continuous spectral band, a white light source included, is discussed.

The results of the experiments of registration and copying of rainbow holograms reconstructing both monochromatic and colored images are presented. 1 .

The properties of photographic plates PFG-04 based on the non-hardned dichromated gelatin are discussed.

The results of work of the holographic studio of the State Optical Institute which is equipped with multicolor pulsed lasers and continuous wave lasers as well as appropriate photomaterials are presented. In this studio any technique of recording can be realized in pratice for various objects including alive. Maximum size of monochrome holograms is 1. 2 x 0. 8 m and color holograms is 60x40 cm 1. INTRODtXT ION At present the display ho lography is the most mass appl icat ion of ho lographic methods popul ar among the populat ion. Due to the permanent interest of holographers to production of display holograms the methods of their recording are now brought to perfection and quality of holograms is of such a level that an observer in a number of cases prefers the holographic image to the original. Such progress in display holography allows transition from technical problems of image quality improvement to problems of artistic representation of objects and forms of the world around. Organization of holographic studios is one of the ways for realization of such a transition. These holographic studios provide the possibility of systematic recording of a wide range of objects and compositions including peopl. nd animals. The first steps in this direction were made in the USSR and USA in 19671970 now the holographic studios exist also in other countries. Broad prospects in realization of artistic

The results of the investigation of small-sized laser system on crystals KGd(W04)2 coherence are presented. This laser system generates pulses with durat i on of 3 ns or 0 . 2 ns . The i nvest i gat ion of the rec i pros i ty 1 aw and hologram diffraction efficiency of silver halide holographic materials on these durations are reported. With the help of this hololaser hologram recordings of diffuse objects are produced. 1 .

Ho 1 ographic character ist i cs of 14A3 s i ngle- layer and mul ty- 1 ayer photoplates of laboratory production with sensitization to red and green spectral regions for transmission-type colored pulsed hologram recording are studied as well as new industrial llt3r-oi materials sensitization to red spectral region. The recording of colored holograms is possible with the use of either separate plates with the narrow sensitization or of photolayers sensitive to the broad spectral zone. For records in green regon of the spectra the good results are providet by BPII and (MIP photoplates . For records in the red region the indastrial llT-oi photoplates are developed. The conditions of optical and chemical sensitization were optimized to provide the best holographic characteristics under the exposure by pulsed (nanosecond pulse duration included) as well as by continuous radiation. To increase the sensitivity the photo-plates were hypersensitized in tn-ethanol amine water solutions of 110 concentration. Five minutes bathing in water or in weak tn-ethanol amine water solutions increases the sensitivity by a factor of 2-3. The increase of concentration up to 10 results in sensitivity growth in the region of short expositions however the values of maximum diffraction efficiency are decreased. To increse the photostability the processing in methil viologen solutions was used . Here the diffraction efficiency is not changed after the irradiation by the filament lamp of 200 lx illumination

In this paper the freerunning ruby laser construction that can be used to produce the Denisyuk''s display holograms is presented. Recording and processing conditions that provide the high qualitative holograms registration are studied. 1 .

Considered within the limits of paraxial off-axis approximation is the image calculation technique where the image is reconstructed by the reflection hologram taking into account the position of the point of observation. Shown is the effect of the size of the eye pupil and its position on distortions of the reconstructed image of the standard object. 1. CALCULATION OF IMAGE POSITION In the known papers devoted to the hologram recording and reconst ruction geometryi2 the coordinates of the image point are determined from the known coordinates of the object point reference and reconstructing sources. This approach however does not account for the well known experimental fact i. e. the dependence of the image posit ion and form on the observer''s position. Let us consider an ordinary case of recording and unconjugate reconstruction of the hologram of a point object. When a photographic plate is illuminated with coherent light from a reference source and point object an elementary hologram with a definite geometry will be recorded in each element of its surface with respect to the angles of incidence of the reference and object beams. When reconstructing the obtained hologram with unconjugate source each element of the hologram will reconstruct its image and the summary image reconstructed by the whole hologram will take the finite region in space. Fig. l shows the images calculated for four points of the hologram under the conditions: y0 cm z0 cm RR cm R56 Rc2O cm ac560. Let us determine which image can be seen when observing from point N located in axis Z with coordinate zN cm. Taking into account the direction of the elementary reconstructed beams following from the hologram we may be sure that only one elementary beam emerging from the hologram region close to the estimated point 3 passes through the point of observation. The other elementary beams forming the image run in different directions and do not pass through point N. When observing from the point with coordinate ZN cm the image of point 4 can only be seen and with ZN being less than 9 cm the image will not be seen at all if the hologram size equals 12 cm. The given example reaffirms the need for obligatory account of the observer''s position when calculating the image reconstructed by the hologram. 62 / SPIE Vol. 1238 Three-Dimensional Holography: Science Culture Education (1989)

If considered as a multichannel data-transmission system, a light-recording medium becomes theoretically tractable within a framework encompassing signals, noises, and differential sensitivity. Attention is given within such a framework to the case of space-time light modulators, avoiding the noise generation and distortions associated with the transfer nonlinearity of the object field amplitude; effective holographic sensitivity, dynamic range, and power consumption/data-bit recording are calculated. A holographic recording scheme is optimized for minimum recording light energy.

The main purpose of the study was to achieve maximum resolution for the photothermoplastic niedia(PTPM) in order to exploit this PTPM i_n the devices of coherent optical data processing and holographic interferotnetry. The achievement of optiniuin characteristics is possible not only with the improvement of the PThM but through the development of universal control equipment as well. The results of the study showed the expediency of the work on FTPIvItype choice and ETPM processing in order to achieve limit parameters and high repeatabi1ity of results. 2. PHOTOTMOPTI MEDIA WITH ORjIC AND IORGANIC PHOTOSEMICONDUCTORS FOR HOLOGRAM RJORDING Photothermoplastic widely used in holography due to their rewriting capability absence of photochernical processing and SPIE Vol. 1238 Three-Dimensional Holography: Science Culture Education (1989) / 271

In the framework of the coupled wave theory the dependence of the light intensity distribution in the holographic image of an extended object on the Bragg angle mismatch has been found for the phase-amplitude 3-D reflective hologram the intensity distribution across the object being arbitrary. The grey level distortions induced by this hologram have been evaluated depending on the observation point position with respect to the hologram and the reconstructing source. 1 .

In the framework of the kinematic theory of three dimensional holograms an analytical expression for the impulse response of a 3-D reflective hologram in a paraxial approximatation has been obtained. The problem of applicability of the transfer function concept to a 3-D reflective hologram has been studied and it has been shown that even in a paraxial domain this hologram can he regarded as a space-invariant system only at small deviation from the Bragg condition. The analytical expression defining the transfer function of a 3-D reflectiye hologram has been derived for this case. The formulae obtained allow to rapidly evaluate the quality of the reconstructed image.

The properties o a new silver halide photographic material for holography in intersecting beams are presented. The energy sensitivi-. ty is io-4 J/crn2 the diffraction efficiency is 20 the resolv-. ing power is 4500 5000 line/mm. The high sensitivity of the photo-. graphic material allows it to be used for holography of living objects. At the Institute of Atomic Energy much attention is paid. to devel-'' opment of a wide choice of photographic materials for pulsed holo-'' graphy1 " 7 Table 1 presents the properties of the basic photographic materials of the IAE for holography in the visible and infrared ranges. Table 1 Name of photographic material Max. sens spectra of itivity nm Sensitivity J/c. m2 Resolution line/mm Diffract. efficiency IAE-''530 IAE-. 630 IAE-. 630(2) L4. E69o 530 630 630 690 -io5 5. 1O6 -io6 io6 3000 30OO 2000 -2O0O 2O 30 IAE-''840 1AE-1060 840 860 910 1060 2OO0 1o Recently a number of problems have been raised which could be solved by means of pulsed holography with recording according to the scheme in intersecting beams given photographic materials displaying a greater (by at least two orders of magnitude) sensitivity than those produced by the Soviet industry for these purposes. Among such prob lems are those in the field of in-''vivo studies. At present in a nwn-'' ber of medical institutions researches are being carried out into the possibility of

1. Denisyuk display hologram o± crystals recording is based on further improvement of illunilnating technique during recording. This paper deals ith optimal Variants of optical schemes for producing 3D holograms o1 diamonds and cut crystals vith characteristic "play" during reconstruction. One of1 the main requirements for illuminating of cut crystals is that light passing through areas and through faces of crystal top coincide in the plane of photographic plate and interfere with illuminating light. 2. It is advisable to form the image of uncut crystals in interferometers that have plane in v'hich vave fields propa gate toards each other and are mutually coherent. A modified iontgomery interferometer 1 with amplitude division of iave field as used for Denisyuk recording of holograms of transparent objects 8-12 nun in diameter. Thts, the possibility is shovrn for Denisyuk display holograms recording of both cut and uncut crystals ;iith characteristic 'play" which can be used in museum expositions.

Registration of 3D ho1orarns broadens the possibility of using single-crystal tool for imagining and investigating inner inhomogeneities and dynamic stresses in top area of gem diamond, study of which by other techniques,e.g. polarization optics, is difficult or impossible. The difficulty is that the diamond with significant refractive index of 2.42 has comparatively small angle of total internal reflection of 24°50. As a result, with random illumination of the tops of octahedron diamond crystals, both smooth- faceted and with polycentric facets, illuminating light is successively reflected from different farets and absorbed in the crystal or comes out of it in a spot and direction that are difficult to calculate. Optimal schemes of illuminating crystals for recording 3D holograms of smooth faceted octahedron diamonds are given. Analysis of illumination of the crystal with polycentric facets shows that correction of light in the diamond is determined by directivity diagram the width of which depends in inhomogeneity size of the diamond. 3D holograms of diamonds with different reflectivity were produced. For the first time the possibility is shown for registration of holograms for studying stresses in diamond top using single-crystal tool.

Holographic recording has been considered to be a combination of primery photocheinical recording processes and dark stages of development and amplification. Chroinium(VI) ions in lightexposed polymer matrix sites convert to chromium(V) compounds which may be regarded as latent image centres These processes induce a structurephase transmission in gelatin which favours a latent holographic structure with low difraction efficiency1 Water and isopropanol promote a redox process involving chromium(III) chromiumCV) compounds and polymeric medium phase-state modulation in exposed and unexposed areas. ''is

The optical information recorded in dichromate gelatin (DCG) layers Induced the information of a latent. image Which rnder the action of water and alcohols transforms to a relief or Phase image. The action of water vapours ma appreciably increase diffraction efficiency. judging from the assumPtion that the introduction of multiatomic alcohols favours the retention of water'' moecu1es in a lager in the amount sufficient for deve1oment on its exposure and stabilization of chromium complexes1 a " self-development" regim has teen worked out. In this case the diffraction efficiency of recorded hc. 1ograms is c''ose to the theoretical limiting value for flatphase r''e c o rdI ng me (J i a. At present the occurence of a Primary latent holographic image (or structure) in dichromated gelatin (DCG) layers has been recognized The diffraction efficiency (DE) detected at a step of holographic recording is low (about 0. 1-IZ). It was shown earlier /j_ 2/ that the treatment bY water vaours or eXPOSUPC Of the layers under conditions of increased humidity results ma growth of DE up to the values enabling the use of DCG to record information in real time /3/j Latent image centres in exposed DC3 layers are predominantly chromium(V) compounds. It is particulary evidenced by the observed correlation between the rate of formation of Cr(V) compounds in a Photo process and the specific change in DE of a latent image /5/.

The formation mechanisms of relief holograms in liquid photopolymerizable layers are analyzed and noted to involve monomer diffusion from darker to lighter areas. The relief depth obtained increases monotonically with initial layer thickness. After gelation in highlighted areas, the mobility of polymer molecules becomes limited by network bounds and monomer-polymer interdiffusion ceases, so that only monomer diffusion into the gel can restore thermodynamic equilibrium.

A thermodynamic analysis is conducted for volume-hologram formation processes in the layer formed by a two-component, liquid photopolymerizable composition-contained polymerizable monomer and solvent. The formation of both photochemically stable and unstable holograms by a diffusive recording mechanism can be accounted for in terms of the microheterogeneous character of photopolymerization. The principles of recording medium compositions' formulation are presented.

physical regularities of hologram interferogram and speckle pho. tographs recording on photothernioplastic recording media depending upon exposure re''erence. . to. object ratio charge current recording temperature and other paranieters have been found0 A possible application of simultaneous photothermoplastic process in stroboscopic and double. . exposure holographic interferometry averaged holographic interferometry on continuous and pulse Qswit ched lasers has been shown. . 14ost of the known speckle. photographic techniques for displacement control and image processing have been carried out on phototherrnopla. stic carriers i. e. : double and xnultipleexposure speckle. photogra. . phy speckle photography of moving objects subtraction coding image multiplexing etc. 1. E1RIivENT SET Holographic interferograms (HI) were recorded in continuous heli umneon and ruby pulsed lasers field according to a standard outof. axis Leith Llpatnieks scheme. The Presnel correlation scheme was em ployed in the device for the dynamic control of HI and hologram re- 286 / SPIE Vol. 1238 Three-Dimensional Holography: Science Culture Education (1989)

The capability of a hologram to reproduce the three-dimensional image of a real objects - its optical replica, atracts attention of specialists engaged in different domains of science and engineering. Holographic methods for image formation are rather interesting for medicine and biology, for systems of visual information representation (in making versatile simulator, for example) and for facilities of non-destructive testing of units and mechanisms, for simulation, etc. Applications of holography to museum practice seems to be rather promising. In this case holographic methods may be quite timely both as a means of visual information imaging and as a means capable of appreciably raising and improving the state of technical equipment of present-day museums.

A rigorous three-dimensional vector analysis of diffraction by a slanted-fringe anisotropic grating is presented for an arbitrary angle of incidence in three dimensions. The exact formulations of the grating diffraction problem without approximations are presented in terms of characteristic waves and coupled waves. Then, using a series of assumptions, rigorous theory is shown to reduce to various existing approximate theories in the appropriate limits. Planar grating diffraction theory hierarchy is presented. A comparison of diffraction efficiency results from exact rigorous theory and from approximate Kogelnik's theory is made.

When studying the structural features of images composed of a finite set of concrete objects one often faces the necessity to extract and analyse the information concerning their mutual position. A similar task must be tackled in pattern recognition using spatial features, i.e. in the cases of congruent images with coinciding component location even those images are different. An example of an input image compared might be one group of A's and one group of B's which shall be considered congruent only if the respective location of the letters are identical. In cases like that the direct measurement and the comparison of the obtained results appear to be complicated because, with different objects, it's hard to conclusive determine zero points (bench-marks). Holographic correlator would also be of little use even though the objects are similar since the contribution of decisive features to correlation response is too small compared to other features. The present paper is a systematic approach to the solution of the task: analysts and comparison of the images on the bases of structural features.

Light diffraction by thick phase sinusoidal holographic grating in the case of different refractive indices inside and outside of the grating is studied analytically. Singular perturbation method is used to solve Maxwell's equations taking into account strict boundary conditions. As a result closed form expressions for both transmitted and reflected waves are received and analyzed. The dependence of the phase of the diffracted waves upon grating strength is discovered. Possible practical applications of gratings with multiple internal reflections of diffraction orders on boundary surfaces are discussed.

The present theoretical and experimental investigation of angular sensitivity in holograms employing a reference speckle wave gives attention to a novel mechanism which bridged the spatial mismatch of the reference and reconstruction wave structures. By contrast with a simple sinusoidal grating, the hologram has sufficiently great angular sensitivity under rotation about the input hologram plane. Under rotation about the axis parallel to the grating layers, angular sensitivity is a function of the mutual effects of cross-grating angular selectivity and the speckle-structure angular mismatch.

Backward diffraction of the plain wave by the transmission holographic grating is considered theoretically using singular perturbation method. The formulae for the intensities of the most strong reflected orders are found and discussed. The physical nature of backward diffraction is explained using the multylayers model of scattering. 2.

The present review highlights various white light holographic dis-'' play techniques which were investigated in the recent past at CSIO Chandigarh. New methods have been proposed for recording inbuilt reference beam rainbow holograms multiplexed restricted aperture reflection holograms fullview rainbow-reflection and composite holo grams and large s ize rainbow holograms. 1.

Some well known development and bleaching processes for silver halide photographic emulsions are compared. Measurements of the most important characteristics diffraction efficiency scattering and reconstructed wavelength were carried out on holographic gratings. Based on these experiments a simple and inexpensive development-bleach process which yields excellent results is proposed. 1.

We show how to cancel the nonlinear aberration in optical systems for holographic 3D reduction. Telescope-like and more elaborated zoom-like systems are shown to produce undistoiled 3D demagnified images within a wide range of arbitrary magnification values. 1.

In this paper we used a novel method for synthesizing computer gene rated images in which by means of a series of intermediate holograms recorded on Fe--doped LiNbO crystals a high quality flat stereograni with wide view angle and much deep 3D image ha been obtained. 2. INTRODUCTITJN As we all know the conventional holography is very limited. With the help of a contineous wave laser only stationary objects can be re corded due tO its insufficient power. Although some moving objects could be recorded by a pulsed laser the dimensions and kinds of object are restricted. If we would like to see a imaginary object or a three dimensional image designed by computer it is very difficult by means of above conventional holography. Of course if we have a two-dimensional image on a comouter screen we can rotate it to give a three-dimensional perspective but we can never really see it as a solid. However flat holographic stereograrns synthesized from computer generated images will make one directly see the comoute results in the form of 3D image. Obviously it will have wide applications in design architecture medicine education and arts. 406 / SPIE Vol. 1238 Three-Dimensional Holography: Science Culture Education (1989)

Reflection gratings are recorded with red (647 . 1 nm) green (514 . 5 nm) and blue (488 . 0 nm) laser light respectively using quasipanchromatic photopolymer plates . The curves of percent transmission versus wavelength and reconstructed wavelength versus exposure for the gratings are given . Using subtractive filters colour reflection holograms are recorded with red green and blue laser light simultaneously. 1. INTRODUCT ION Reflection holograms were invented by Denisyukin 1962 . It has been desired to reconstruct a vivid colour reflection hologram . But there are two difficulties for making it : one is that recording reflection holograms with green and blue light demands high resolution to recording material the other problem is that reconstructed wavelength of a reflection hologram varies with the swell or shrinkage of recording material . Kubotat reported the recording of high qual ity colour reflection holograms with the combination of DCG and si iver halide plates in 1986. Since the study on the photopolymer from 1970 there are many detailed reports on transmission volume hologram. But not until 1985 did R. T. Ingwell and H. L. Fie1ding(Polaroid Company) report the recording of reflection gratings with DtIP-128 photopolymer and they also reported the recording of reflection hologram wit. h DMP-128 in 1986. Photopolymer material is apt to be made as quasipanchromatic . In order to record reflection holograms with homemade photopolymer4 we have separately

The feasibility of using a holographic lens as a coupler in a fiber-optic gyro that is conceived as a ring Sagnac interferometer is experimentally assessed, and the equivalent Bragg condition for holographic gratings is discussed together with the Q factor for slanted gratings. The present holographic couplers yield superior splitting ratio and polarization nonsensitivity; they are also easily constructed and low-cost. The recording medium used is dichromated gelatin, which possesses high diffraction efficiency and low noise.

Since the 1985 Lake Forest International Conference on display holography (USA) more developments have been made on holographic applications in China among which the important events and progress were: the International Conference on holography applications em bossing holography new holographic optical elements and equipments etc. . 1. INTERNATIONAL CONFEPENCE ON GRAPHY APPLICATIONS'' ( I CHA ''86. BEIJING) More than 280 holographers from 18 countries gathered in the Science Hall in Beijing from July 2 to for the International Conference on holography applications''86. The conference was sponsor ed by the Chinese OPtical Society the Chinese Theoretical Applied Mechanics Society and cosponsored by the Society of Photooptical Instrumentation Engineers the European Photonic Association in cooperation with the China Association for Science And Technology. It was chaired by Prof. Wang Daheng vice president of the China Association for Science Technology and president of the Chinese Optical Society cochaired by DP. H. J. Caulfield of the Univ. of Alabama Dr. G. von Bally of the Munster Univ. in West Germany and Dr. J. Tsujiuchi of the Tokyo Institute of Technology. SPIE Vol. 1238 Three-Dimensional Holography: Science Culture Education (1989) / 13

The Musde l''Holographie opened its doors in March 1980 to promote holography which until then was not to the general public. Its activities include exhibits held in France and abroad education and information such as workshops seminars and conferences the making of holograms and international cultural and scientific exchanges.

Gisele Freund states that every historical epoch has its own artistic modes of expression that reflect the political character. thoughts and tastes of the times ill. At another point she writes that each society creates its own particular modes of expression largely through its life-style and tradition and that these modes in turn reflect the epoch. Every change in society influences the theme and type of artistic representation [2]. If one agrees with Freund's point of view . it becomes necessary to look at holography from a perspective different from those used up to now. We have to ask in which way and using what aesthetic methods and means does holography correspond with the thoughts and tastes of our times or. to put it differently. whether the aesthetic message of the medium is able to influence as well as express the characteristics and trends of the present experience. Above all, it is essential to examine what holography is and how this medium articulates its aesthetic message. This is not intended to be another detailed explanation of the technical principles of the recording and reconstruction of a hologram. which has already been done innumerable times 13]. Of more importance here is the intention to investigate the aesthetic side of the medium.

A method for displaying 3D images of medical objects by using holographic stereogram is described together with basic properties of reconstructed images of cylindrical holographic stereograms. INTRODUCTI ON A holographic stereogram (HS) is a synthesized hologram from an original film which consists of a series of ordinary photographs taken from different directions of an object and is possible to apply to an object whose hologram is very difficult or impossible to take with conventional techniques [U. Such a feature of HS can be used for 3D display of medical images such as X-ray images computer assisted tomogrphy (CT) images nuclear magnetic reasonance images (MRI) or ultrasonic images of a patient. CYLINDRICAL HOLOGRAPHI C STEREOGRAMS The original film of the medical HS is taken by rotating around the body axis of a patient a U-shaped arm equipment one end of which has a pulse X-ray source and the other end a movie camera with an image intensifier [2]. Synthesis of HS is carried out by using a special optical system the hologram is shaped into a cylinder and is reconstructed by illuminating the hologram with a small white light source located on the axis of the cylinder. Such a HS is called multiplex hologram (MH) the most popular HS and the reconstructed image can be observed in the cylinder. The formation of reconstructed image is made in unusual way and fundamental properties

In the present paper holo-interferometric fringe patterns are recorded within a cavity using two opposing collinear panoramic annular lenses. One panoramic annular lens is used to illuminate the cavity wall with coherent light and the resulting intensity distribution is holographically recorded through the second panoramic annular lens. Interference fringes are obtained in real time by comparing holograms recorded before and after the cavity shape is modified. Future plans are discussed for practical implementation of the method including the use of digital image processing with a minicomputer for automatically accessing and analyzing the fringe patterns recorded through the system and the incorporation of fiber optic components for making holographic measurements within the cavity using a compact rugged probe. 1.

Among the many uses of holography, the most frequently lauded are display, interferometry, HOE, and a myriad of other technical applications. Seldom mentioned is its important contribution to culture and education, the theme of this conference. Herein we wish to argue a case for holography in culture and education, and detail the steps we have taken to implement it to a broad spectrum of the U. S. public over the last twenty years. With the consolidated effort of colleagues around the world, we expect the subject of holography to become an integral part of basic education for all.

The authors of the present paper have been working together in the field of holographic art during the last three years. Our holographic works of art are based on the use of the Denisyuk reflection holograms. These holograms make it possible to creat an art image with the help of the completely new means of representation. The increase of the reflection holograms size could widen the possibilites of art holography. For example , the high quality holograms C size 60x80 cm ) are produced in the USSR. Assembled into large-sized panels, they can be used both in advertisments, interior decoration and in creating unique works of art. They can also be used for decoration of Christian cathedrals and churches, where such art holographic compositions would produce great impressin on people. Here we'd like to discuss the problem of an aesthetic perception of a holographic image.

It has been a long and elusive goal of display holographers to produce true multicolored images closely matched to that of the object. Much progress has been reported ecently by K. Bazargan1-'' T. Kubota2 P . M. Hubel and A. A. Ward '' and H. Owen and A. E . Hurst (6) However most of the works reported require sandwiches of different materials independently exposed. Herein we wish to report our recent work in " true color" holography using single lements of silver halide dichromated gelatin as propose by J. Blythe and the Du Pont photopolymer material. Also new sandwich combinations are reported. 2. HEURISTIC DEFINITION OF " TRUE" COLOR" Since laser light is required to record holograms the reconstructed image by an incandescent source will never recreate precisely the image of a multicolored object as it appears under natural lighting. At least two major factors contribute to this problem: the object may fluoresce and the reconstruction bandwidth will always be wider than laser lines causing color desaturation. Furthermore because color perception is subjective there cannot ever be complete agreement among different observers as to the " truthfulness" of the reconstructed image. We offer the following heuristic definition which is amenable to scientific verification: A hologram is said to have " true color" if it recreates an image which has the same combination of wavelengths and their relative intensities as those

Colour cross talk and viewing range of images with multicolour rainbow holograms are dis cussed in detai 1 . The chromaticity equations of a reconstructed multiclour image are given . A me thod of one-step multicolour rainbow holograms using concave mirror and field lens is presented. 1.