5.16 Results and Conclusions
479
automatization of spectro-metrical measurements: information collection, Fourier
analysis, statistical processing and graphic means of visualization of the derived
results. The possibility of using the majority of classical methods of spectral
estimation based on the algorithm of quick Fourier transformation is realized in
it.
The laser specklometer is protected by the certificate of authorship of the USSR
No. 1620037 (11.07.08) and does not have analogs on the territory of the former
USSR and countries of Eastern Europe. The device possesses novelty in regard to
countries of the former USSR, USA and Germany.
6. The preliminary studies of characteristics of reconstructing of illuminating–
receiving head and the whole laser specklometer with the help of calibrated
vibrator were conducted. It was shown that for the frequency of oscillations of
50 Hz during the increase of the amplitude of oscillation from 4 to 10.7 μm
and during the usage of reconfigurable illuminating–receiving head only one
main harmonic (others were more than 100 times smaller in their amplitude) was
observed in the spectrum. During this, the dependences of amplitude changes of
spectral harmonic and the area under spectral curve on the oscillation amplitude
of the surface of the vibrator under study were practically linear. This fact during
deciding the issue of normalizing the signal allows using laser specklometer for
the quantitative estimation of not only the frequencies, but also the amplitudes
of vibrations of the surface under study, and also its little movements. Additional
studies of laser specklometer with the help of calibrating vibrator showed that the
measurements conducted with the use of reconfigurable illuminating–receiving
head are practically linear in the range from 4 to 11 μm, and consequently it gives
the possibility to conduct qualitative estimation of the amplitudes and frequencies
of oscillations under study.
7. With the aim of development of speckle-optical technique, the studies of
amplitude–frequency characteristics of ultrasonic acoustic transformer of
YZPYA2M3.507.178 type were conducted.
Resonance USWS frequency was determined, and the dependence of oscillation
amplitude of the working end of USWS microinstrument on frequency of vibrations
and current of transformer near resonance was obtained.
These characteristics are necessary for the optimization of calculations and
construction of USWS. The derived information was compared with the results of
the studies with the help of the laser Doppler vibrometer.
In these studies, the following was used: the sample of laser specklometer—device
designed for registration in relative units of temporary fluctuations of intensity of
speckle-field, formed as a result of scattering by vibrating diffuse objects of radiation
and calculation of their amplitude–frequency characteristics during collaboration
with computer.
The laser specklometer allowed measuring the amplitude in the range of 1–15 μm
and the frequency of vibration in the range of 1–2000 Hz with the resolution power
of 1 μm.
479
automatization of spectro-metrical measurements: information collection, Fourier
analysis, statistical processing and graphic means of visualization of the derived
results. The possibility of using the majority of classical methods of spectral
estimation based on the algorithm of quick Fourier transformation is realized in
it.
The laser specklometer is protected by the certificate of authorship of the USSR
No. 1620037 (11.07.08) and does not have analogs on the territory of the former
USSR and countries of Eastern Europe. The device possesses novelty in regard to
countries of the former USSR, USA and Germany.
6. The preliminary studies of characteristics of reconstructing of illuminating–
receiving head and the whole laser specklometer with the help of calibrated
vibrator were conducted. It was shown that for the frequency of oscillations of
50 Hz during the increase of the amplitude of oscillation from 4 to 10.7 μm
and during the usage of reconfigurable illuminating–receiving head only one
main harmonic (others were more than 100 times smaller in their amplitude) was
observed in the spectrum. During this, the dependences of amplitude changes of
spectral harmonic and the area under spectral curve on the oscillation amplitude
of the surface of the vibrator under study were practically linear. This fact during
deciding the issue of normalizing the signal allows using laser specklometer for
the quantitative estimation of not only the frequencies, but also the amplitudes
of vibrations of the surface under study, and also its little movements. Additional
studies of laser specklometer with the help of calibrating vibrator showed that the
measurements conducted with the use of reconfigurable illuminating–receiving
head are practically linear in the range from 4 to 11 μm, and consequently it gives
the possibility to conduct qualitative estimation of the amplitudes and frequencies
of oscillations under study.
7. With the aim of development of speckle-optical technique, the studies of
amplitude–frequency characteristics of ultrasonic acoustic transformer of
YZPYA2M3.507.178 type were conducted.
Resonance USWS frequency was determined, and the dependence of oscillation
amplitude of the working end of USWS microinstrument on frequency of vibrations
and current of transformer near resonance was obtained.
These characteristics are necessary for the optimization of calculations and
construction of USWS. The derived information was compared with the results of
the studies with the help of the laser Doppler vibrometer.
In these studies, the following was used: the sample of laser specklometer—device
designed for registration in relative units of temporary fluctuations of intensity of
speckle-field, formed as a result of scattering by vibrating diffuse objects of radiation
and calculation of their amplitude–frequency characteristics during collaboration
with computer.
The laser specklometer allowed measuring the amplitude in the range of 1–15 μm
and the frequency of vibration in the range of 1–2000 Hz with the resolution power
of 1 μm.