108
2 Holographic Microscopy of Phase and Diffuse Objects …
mechanism of optical radiation distribution in biological tissue (in this case—it is
nerve tissue) remains unexplained at a cellular level.
In the present work, the holographic study of refraction structure of the living
nerve fibers is carried out. In particular, there were measured radial distribution
of Schwann’s sheath refractive index, the axon of myelinated nerve fiber and also
myelinated nerve fibers.
Aging preparations of single myelinated nerve fibers (the diameter is 8–10 μm at
the length λ of the dissected area of 5–7 mm) taken from the brown frog sciatic nerve
and nerve cells appendices grown in the sympathetic ganglion dissociated culture
served as the object of the study [333]. The laser-holographic block-scheme of the
setup for the study of structure-functional characteristics of neurobiological objects
is presented in Fig. 2.14. The setup designed for these purposes consists of two parts:
a holographic one and an electrophysiological one.
The holographic part includes the source of radiation—continuous wave laser LG38 (50 mW) in many cases containing a stroboscope, an adjustment laser LG-56, holographic microscopes operating for transmission and in the reflected light (Fig. 2.15),
with the help of which studies of phase and diffusing microobjects altered their
state were conducted, as well as a real-time hologram processing equipment. This
equipment allows obtaining holograms and holographic interferograms in different
actuation phases of nerve fibers using the time-elapsed method of real-time holographic interferogram recording, including differential holographic interferometry,
and the stroboscopic one.
1. The double-exposed method of microobjects holographic interferogram
recording consists in consecutive recording of two microobject states on one
detecting medium: the initial and the modified one, for example, with stimulation
electric or laser influence.
2. Term “real time interferometry” means that the interferometric pattern alters
simultaneously with the object state alteration. In this case, the hologram is
exposed one time, is developed and fixed on the same place, where it was during
the survey or is processed directly on the detecting point.
3. Stroboholography is holographic repeated processes research methods when
holograms are exposed in the light of following light pulses, which are
synchronized with a certain process phase.
The holographic interference microscope has the following characteristics:
Size of registered objects From 1 μm up to 3 mm
Hologram registration time:
Working with a continuous wave
laser LG-38
5 × 102 :30 s
Working with a pulse ruby laser 3 × 10
−8 c
Real-time hologram detection time using strobe
Pulses with off duty ratio 100 1/100 s
2 Holographic Microscopy of Phase and Diffuse Objects …
mechanism of optical radiation distribution in biological tissue (in this case—it is
nerve tissue) remains unexplained at a cellular level.
In the present work, the holographic study of refraction structure of the living
nerve fibers is carried out. In particular, there were measured radial distribution
of Schwann’s sheath refractive index, the axon of myelinated nerve fiber and also
myelinated nerve fibers.
Aging preparations of single myelinated nerve fibers (the diameter is 8–10 μm at
the length λ of the dissected area of 5–7 mm) taken from the brown frog sciatic nerve
and nerve cells appendices grown in the sympathetic ganglion dissociated culture
served as the object of the study [333]. The laser-holographic block-scheme of the
setup for the study of structure-functional characteristics of neurobiological objects
is presented in Fig. 2.14. The setup designed for these purposes consists of two parts:
a holographic one and an electrophysiological one.
The holographic part includes the source of radiation—continuous wave laser LG38 (50 mW) in many cases containing a stroboscope, an adjustment laser LG-56, holographic microscopes operating for transmission and in the reflected light (Fig. 2.15),
with the help of which studies of phase and diffusing microobjects altered their
state were conducted, as well as a real-time hologram processing equipment. This
equipment allows obtaining holograms and holographic interferograms in different
actuation phases of nerve fibers using the time-elapsed method of real-time holographic interferogram recording, including differential holographic interferometry,
and the stroboscopic one.
1. The double-exposed method of microobjects holographic interferogram
recording consists in consecutive recording of two microobject states on one
detecting medium: the initial and the modified one, for example, with stimulation
electric or laser influence.
2. Term “real time interferometry” means that the interferometric pattern alters
simultaneously with the object state alteration. In this case, the hologram is
exposed one time, is developed and fixed on the same place, where it was during
the survey or is processed directly on the detecting point.
3. Stroboholography is holographic repeated processes research methods when
holograms are exposed in the light of following light pulses, which are
synchronized with a certain process phase.
The holographic interference microscope has the following characteristics:
Size of registered objects From 1 μm up to 3 mm
Hologram registration time:
Working with a continuous wave
laser LG-38
5 × 102 :30 s
Working with a pulse ruby laser 3 × 10
−8 c
Real-time hologram detection time using strobe
Pulses with off duty ratio 100 1/100 s