160
2 Holographic Microscopy of Phase and Diffuse Objects …
Specially for these purposes, there was developed and manufactured the camera
for electrostimulation and biopotential derivation of the nerve fiber, which contains an
optical part that enabled to conduct studies simultaneously using two independent
methods: the electrophysiological one and the interference holographic one. New
methods of preparation and electrophysiological control of neuromuscular tissue
preparation viability (nerve, muscle fiber, nerve fiber) are mastered. The system
of synchronization provided firing of the laser pumping block with a sync pulse
from the electrical stimulator. The delayed relative to the firing one stimulation
pulse excited the nerve fiber. In this case, the lightening of the nerve fiber with the
laser pulse coincided with passing through its action potential. The recording of
holographic interferograms of the nerve fiber was conducted in different excitation
phases, provided by the delay line and the synchronization system.
The methods of holographic microscopy and interferometry were developed for
studying intravital states of the neuromuscular tissue [1, 2, 3, 5, 7, 8, 9, 10, 11, 15].
The defocusing impact on the formation of holographic interferograms (changes of
band shape, contrast), which is caused by the longitudinal object shift, was studied. It
is shown that the implementation of lenses in the schemes of holographic interferometry gives no possibility to enhance sensitivity to the longitudinal shift measurement
but improves the spatial resolution. The contrast of the interference pattern emerged
under the shift of the diffuse object is defined by the function, which is a threedimensional pulse response of the lens with the argument equal to the shift vector.
There were examined cases for plane mirror and the diffuse object shift. For the latter
case, it is shown that the range of the shifts measured is limited by the depth of focus
of the lens. The conducted study confirms in terms of quantity the qualitative conclusions about the limits of possible shifts in the holographic interferometry schemes.
The range increase of the object longitudinal shifts can be reached by the loss of resolution by aperture decrease. During the interference study of objects, which change
amplitude distribution of the illuminating beam, it is important to consider the fact
that defocusing distorts the image itself as well as the phase difference between the
images.
The experimental samples of holographic microscopes were developed, which
operate on transmission and in the reflected light and applicable for the study of
phase, specular reflected and diffusing microobjects that change their state with
time. For the first time, the possibility to study the structures of nerve fibers, muscle
fibers, lymphocytes was shown using the holographic microscopy and interferometry
methods. The conditions of nerve fiber hologram and holographic interferogram
forming were studied, which made it possible to single out and visualize its main
structural formations.
There was shown the absence of noticeable damaging effect of the laser radiation
in doses necessary for hologram and holographic interferogram recording on the
structure and the function (action potential transmitting) of the nerve fiber. Also,
optimal conditions for hologram and holographic interferogram recording of a nerve,
a muscle fiber, lymphocytes were studied in the bands of finite and infinite width.
The method of single nerve cells cultivating was perfected (dissociated cultures).
Recording of bioelectrical activity of a single nerve cell was mastered. The possibility
2 Holographic Microscopy of Phase and Diffuse Objects …
Specially for these purposes, there was developed and manufactured the camera
for electrostimulation and biopotential derivation of the nerve fiber, which contains an
optical part that enabled to conduct studies simultaneously using two independent
methods: the electrophysiological one and the interference holographic one. New
methods of preparation and electrophysiological control of neuromuscular tissue
preparation viability (nerve, muscle fiber, nerve fiber) are mastered. The system
of synchronization provided firing of the laser pumping block with a sync pulse
from the electrical stimulator. The delayed relative to the firing one stimulation
pulse excited the nerve fiber. In this case, the lightening of the nerve fiber with the
laser pulse coincided with passing through its action potential. The recording of
holographic interferograms of the nerve fiber was conducted in different excitation
phases, provided by the delay line and the synchronization system.
The methods of holographic microscopy and interferometry were developed for
studying intravital states of the neuromuscular tissue [1, 2, 3, 5, 7, 8, 9, 10, 11, 15].
The defocusing impact on the formation of holographic interferograms (changes of
band shape, contrast), which is caused by the longitudinal object shift, was studied. It
is shown that the implementation of lenses in the schemes of holographic interferometry gives no possibility to enhance sensitivity to the longitudinal shift measurement
but improves the spatial resolution. The contrast of the interference pattern emerged
under the shift of the diffuse object is defined by the function, which is a threedimensional pulse response of the lens with the argument equal to the shift vector.
There were examined cases for plane mirror and the diffuse object shift. For the latter
case, it is shown that the range of the shifts measured is limited by the depth of focus
of the lens. The conducted study confirms in terms of quantity the qualitative conclusions about the limits of possible shifts in the holographic interferometry schemes.
The range increase of the object longitudinal shifts can be reached by the loss of resolution by aperture decrease. During the interference study of objects, which change
amplitude distribution of the illuminating beam, it is important to consider the fact
that defocusing distorts the image itself as well as the phase difference between the
images.
The experimental samples of holographic microscopes were developed, which
operate on transmission and in the reflected light and applicable for the study of
phase, specular reflected and diffusing microobjects that change their state with
time. For the first time, the possibility to study the structures of nerve fibers, muscle
fibers, lymphocytes was shown using the holographic microscopy and interferometry
methods. The conditions of nerve fiber hologram and holographic interferogram
forming were studied, which made it possible to single out and visualize its main
structural formations.
There was shown the absence of noticeable damaging effect of the laser radiation
in doses necessary for hologram and holographic interferogram recording on the
structure and the function (action potential transmitting) of the nerve fiber. Also,
optimal conditions for hologram and holographic interferogram recording of a nerve,
a muscle fiber, lymphocytes were studied in the bands of finite and infinite width.
The method of single nerve cells cultivating was perfected (dissociated cultures).
Recording of bioelectrical activity of a single nerve cell was mastered. The possibility