الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
Coherent optical data processing has captured the imagination
and attention of many researches. This interst is due to the potential
advantages of optical processors compared to digital or other analog
systems. An optical data processor is a two - dimensional system in
which all points in the input plane of a lens are operated on in parallel.
This is in contrast to other processors which are inherently serial and
which require extensive duplication of circuitry of components to
achieve parallel processing. Coherent optical processors can also
inherently perform Fourior transforms, correlations and convolutions on
two dimensional data.
Many applications for these operations have been described in
several survey articles {1-9]. Perhaps the major interest in optical
computing lies in the high data through put possible. The above
operations can be performed in parallel on two - dimensional data at
processing rates that can approach the speed of light. It is limited only
by the input and output transducers and the rate at which data can be
placed in the system.
In most coherent optical processors, data was recorded on
photographic film. Furthermore, no universal set of specifications and
device characteristics was appropriate for all applications.
In the first chapter, the spectral sensitivity and resolution of the
different types of holographic pieties were discussed. Effect of the
linearity for characteristic curve 011 the quality of the images was also
studied. The superposed noise and distortions were results of increased
recorded images on the same phatagraphic plate. To increase the
efficiency of the hologram, the amplitude hologram must be converted
to phase hologram by bleaching processes.
Numbers of information processing techniques were described in
chapaters II, III and IV. The low frequency optical signal was
modulated by amplitude crossed gratings as in chapter II. The effect of
exposure time and bleaching processes on the quality of images were
studied. A method of storing a number of real amplitude images on the
same phtographic plate by modulating each image on a differe!1t spatial
carrier was described. The contrast and signal - to - noise ratio were
also studied. To record the two amplitude objects on the one array of
the crossed grating and retrieve each after the other, the crossed grating
must be changed by another frequency. Some letters and numbers were
used as amplitude objects.
In chapter III, the effective the phenomenon of cross-talk on the
retrieved images was studied. Two amplitude objects were recorded on
the same photographic plate. The signals were modulated by a random
diffuser. The double exposure technique was used. The photographic
plate was shifted when recording the two amplitude objects. The lateral
shift between the two exposures was 10J.11Il for all processes. The
capacity and the signal to noise ratio as a result of the orientation of the
cross - talk were studied theoritically and experimentaly.
In chapter IV, two techniques were used to detect the optical
difference between two images. Some latters and Effil tower were used
as amplitude objects. The first technique used the ground glass as a
modulated signaL The double exposure teclmique was used. There was
lateral shift between the two exposures. The two amplitude objects
were identical but there was small difference betwen them. The second
technique was studying the effect of introducing a glass wedge between
an amplitude grating and its self-images. The subtraction betwen two
amplitude objects was also discussed.