408
5 Laser Specklometer, Speckle-Optical Diagnostics and Laser …
Fig. 5.23 Calibration curve of dependence of the first spectral harmonic amplitude A 1 on vibrator
oscillation amplitude A v . Reprinted from [87] with permission
Fig. 5.24 Dependence of the oscillation of the first spectral harmonic A 1 from the oscillation
amplitude of a calibrated vibrator A 8 . Reprinted from [87] with permission
speckle. But meanwhile the intensity of the received signal decreases significantly
that will lead to the necessity of using a more powerful radiation source.
Verification of the second controlled parameter f 0 is conducted due to the experimental scheme shown in Fig. 5.17. f 0 is the frequency of the main spectral harmonic
calculated according to the speckle-field intensity fluctuations registered with a laser
specklometer, and the speckle-field was formed during diffusion of the laser radiation
from the diffusive reflector of the reference vibrator.
Sinusoidal electric signals were fed from the signal generator 12 onto the calibrated vibrator 11 serially on three fixed frequencies 4 in each of the set ranges of
5 Laser Specklometer, Speckle-Optical Diagnostics and Laser …
Fig. 5.23 Calibration curve of dependence of the first spectral harmonic amplitude A 1 on vibrator
oscillation amplitude A v . Reprinted from [87] with permission
Fig. 5.24 Dependence of the oscillation of the first spectral harmonic A 1 from the oscillation
amplitude of a calibrated vibrator A 8 . Reprinted from [87] with permission
speckle. But meanwhile the intensity of the received signal decreases significantly
that will lead to the necessity of using a more powerful radiation source.
Verification of the second controlled parameter f 0 is conducted due to the experimental scheme shown in Fig. 5.17. f 0 is the frequency of the main spectral harmonic
calculated according to the speckle-field intensity fluctuations registered with a laser
specklometer, and the speckle-field was formed during diffusion of the laser radiation
from the diffusive reflector of the reference vibrator.
Sinusoidal electric signals were fed from the signal generator 12 onto the calibrated vibrator 11 serially on three fixed frequencies 4 in each of the set ranges of