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3 Holographic Interferometry for Studying …
This fact was established to significantly weaken the interferogram contrast up
to 3–5 s of uncertainty while using multilayer RCs with an underlayer, which has
surface resistance of 3–4 kohm/cm
2 . But for single-layer RCs relaxation of the static
surface discharge at time up to 10 s does not influence the quality of the interferogram.
It was ascertained that the interferogram quality, which is provided by the
photothermoplastic RC, is reached if all the firm requirements to the stability of
the recording parameters are met. Thus, the evenness of development temperature
along the frame surface should be not lower than 0.2:0.4 relative to the optimum,
which is selected for every type of RC and lies within the limits of 60–80 °C.
The schemes of obtaining “living” interference fringes using two reference beams
were studied. As a basic variant, a scheme was selected with reference beams situated
in a vertical plane and with a focused image. This scheme provides the mode of
“living” fringes while using radiation of different length, recording interferograms
of the ruby laser radiation λ = 694.3 nm and its reconstruction with a He–Ne laser
radiation λ = 632.8 nm. The conducted study gave the possibility to select the optimal
optical scheme of the complex, which gives accuracy during estimation, a scheme
of the interferometer with two reference beams and regulated phase shift.
An optical block was developed where the scheme of the interferometer with two
reference beams was realized. The reference beams are regulated by the phase shift.
The study was conducted connected with elimination of hologram dispersion
impact on the images shift, which appears as a result of different wavelengths of
radiation during recording (λ = 694.9 nm) and reproduction (λ = 632.8 nm) of
interferograms, which give the possibility to use He–Ne laser radiation for interferogram sensing, but preserving the advantages of the two reference beam scheme.
The scheme of compensation node of path difference between reference and object
beams was developed, which is based on the usage of mirror optical loop.
Preliminary medical study was conducted. In order to select research methods of
blood circulation needed for comparison with the holographic interferogram of the
chest, there was conducted the analysis of methods to study mechanical, electrical
and pumping heart activity, as well as methods to study the vascular system, to
measure pressure and time of the blood flow.
The impedance cardiography method was chosen as the most informative way.
It allows quickly obtaining information about pumping and mechanical function
of the heart, about the state of the arterial pressure and peripheric resistance. This
method was realized with the help of “Impecard,” a hard- and software complex. The
implemented algorithm of automatic estimation of hemodynamics indices gives the
possibility to localize all the phase structures of the bioimpedance signal.
Usage of the signal of the chest differentiated impedance plethysmogram was
taken as a principle of the method of data storage about the functional state of
the cardiovascular system of the examined patient. The plethysmogram is obtained
with rheograph R4-02 with synchronous image forming of a chest interferogram for
further development of new diagnostic criteria.
It was established that LHC synchronization system should be connected in the
middle on the ascending and descending branches of the curve of the impedance
3 Holographic Interferometry for Studying …
This fact was established to significantly weaken the interferogram contrast up
to 3–5 s of uncertainty while using multilayer RCs with an underlayer, which has
surface resistance of 3–4 kohm/cm
2 . But for single-layer RCs relaxation of the static
surface discharge at time up to 10 s does not influence the quality of the interferogram.
It was ascertained that the interferogram quality, which is provided by the
photothermoplastic RC, is reached if all the firm requirements to the stability of
the recording parameters are met. Thus, the evenness of development temperature
along the frame surface should be not lower than 0.2:0.4 relative to the optimum,
which is selected for every type of RC and lies within the limits of 60–80 °C.
The schemes of obtaining “living” interference fringes using two reference beams
were studied. As a basic variant, a scheme was selected with reference beams situated
in a vertical plane and with a focused image. This scheme provides the mode of
“living” fringes while using radiation of different length, recording interferograms
of the ruby laser radiation λ = 694.3 nm and its reconstruction with a He–Ne laser
radiation λ = 632.8 nm. The conducted study gave the possibility to select the optimal
optical scheme of the complex, which gives accuracy during estimation, a scheme
of the interferometer with two reference beams and regulated phase shift.
An optical block was developed where the scheme of the interferometer with two
reference beams was realized. The reference beams are regulated by the phase shift.
The study was conducted connected with elimination of hologram dispersion
impact on the images shift, which appears as a result of different wavelengths of
radiation during recording (λ = 694.9 nm) and reproduction (λ = 632.8 nm) of
interferograms, which give the possibility to use He–Ne laser radiation for interferogram sensing, but preserving the advantages of the two reference beam scheme.
The scheme of compensation node of path difference between reference and object
beams was developed, which is based on the usage of mirror optical loop.
Preliminary medical study was conducted. In order to select research methods of
blood circulation needed for comparison with the holographic interferogram of the
chest, there was conducted the analysis of methods to study mechanical, electrical
and pumping heart activity, as well as methods to study the vascular system, to
measure pressure and time of the blood flow.
The impedance cardiography method was chosen as the most informative way.
It allows quickly obtaining information about pumping and mechanical function
of the heart, about the state of the arterial pressure and peripheric resistance. This
method was realized with the help of “Impecard,” a hard- and software complex. The
implemented algorithm of automatic estimation of hemodynamics indices gives the
possibility to localize all the phase structures of the bioimpedance signal.
Usage of the signal of the chest differentiated impedance plethysmogram was
taken as a principle of the method of data storage about the functional state of
the cardiovascular system of the examined patient. The plethysmogram is obtained
with rheograph R4-02 with synchronous image forming of a chest interferogram for
further development of new diagnostic criteria.
It was established that LHC synchronization system should be connected in the
middle on the ascending and descending branches of the curve of the impedance