3.4 Holographic Research Methods in Biology and Medicine
279
Fig. 3.53 Scheme of a
combined image
reproduction. Reprinted from
[94] with permission
photoresists (photoresistive material) are applied for image reflection improvement
the substrate consists of two layers, and the light-sensitive layer is covered with a
reflective layer of silver, aluminum, titanium, chromium or their compounds with
further photochemical processing after the exposure.
In this case, the plane image is reproduced at the expense of reflection of the
incident radiation of the substrate. Depending on distinctive features of the object
under recording (size, color of most marked details of the image) layers of argentiferous emulsions, nonsilver emulsions, negative and positive photoresists are used as
a light-sensitive layer. Any of widely known emulsions is used as an argentiferous
emulsion, and chrome-plated gelatin or shellac can be used as nonsilver emulsions.
Besides, the plane image is formed on a substrate, and its material can reproduce a
plane image at the expense of intrinsic emission, electrochemical, electroluminescent, semiconductor indicators, on which information about an image is programed
and altered under electrical and thermal impact, and when the substrate for the plane
image is an indicator of transient data.
The obtained effect gives the possibility to observe transfer of one image into the
other one, i.e., transfer of the two-dimension image into the three-dimensional (holographic) one and vice versa and that makes it possible to implement the combination
of 3D and plane images, which are complementary to each other. Any effect of visual
perception can be obtained with the help of this transfer. In this case, the hologram is
the main component of the image formation method that helps obtaining combined
images. Meanwhile, the hologram is constantly present and forms a multilayer structure with a substrate with a plane image. Arbitrary orientation of substrates with a
plane and a 3D image is possible. Observation of a combination (in space and time)
of 3D and plane images is a complex interconversion, constant image formation and
transfer of the image into the plane one and vice versa and, thus, realizing continuous
obtaining of visual data. Simultaneous regulation of the volume of the incoming data
is mainly determined by the intensity value, the level of spatial coherence, spectral
and polarization characteristics of the light beam (Fig. 3.53). This is reached in particular by the fact that in the image forming method, which consists in recording of
holograms in colliding beams and in reconstructing of holograms by a variable intensity beam and orientation of a two-dimension projection of a reconstructed image
with a focused image of the same object several holograms of the objects are formed
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