ABSTRACT: Acousto-optic diffraction of pulsed laser radiation on a multifrequency acoustic wave has been studied. It is established
that the high efficiency of diffraction (i.e., the formation of a multibeam optical field with low losses) can be also achieved
for a nonequidistant set of frequencies and, hence, nonuniform distribution of beams in the angular space. Results of experimental
verification of the proposed approach are presented.
Technical Physics Letters 05/2012; 37(6):530-533. · 0.56 Impact Factor
ABSTRACT: Bragg’s acoustooptic diffraction in an acoustically anisotropic medium is considered taking into account the two-dimensional
spatial diffraction structure of the acoustic beam. The conditions are determined under which reverse transfer of optical
power from the diffracted to the transmitted beam in the regime of 100% efficiency of diffraction is considerably suppressed.
It is shown that this effect is due to diffraction bending of wave fronts of the acoustic beam in the acoustooptic diffraction
plane. The problem of optimization of the piezoelectric transducer size and the spatial position of the input light beam is
solved using the criterion of the minimal required power of the acoustic field. The results of simulation in a wide range
of the acoustooptic interaction parameters for a Gaussian light beam are reported. The correctness of the model is confirmed
experimentally. Recommendations for designers of acoustooptic devices are formulated.
Technical Physics 05/2012; 55(3):413-422. · 0.50 Impact Factor
ABSTRACT: Bragg acoustooptic diffraction of nanosecond pulsed laser radiation from a frequency- and/or phase-keyed acoustic wave is
studied experimentally and theoretically for exact synchronization of laser pulses and signal keying. It is shown that the
diffraction field for short pulses is practically stationary and is determined by the positions of acoustic signal keying
over signal aperture. The application of this type of signals for the formation of a multibeam diffraction pulsed radiation
field is considered. A method is proposed for transforming the angular spectrum of laser radiation intensity from the initial
Gaussian to a nearly rectangular spectrum. This may considerably increase the efficiency of high-power technological lasers
used in material processing (laser cutting, welding, engraving, etc.), in which the action of radiation is of the thresh-old
type in light intensity. The possibility of correcting the angular intensity distribution for a pulsed fiber laser, which
increases the thermal efficiency of radiation from such a laser, is established experimentally.
Technical Physics 04/2012; 54(11):1626-1632. · 0.50 Impact Factor
ABSTRACT: A new effect, viz., acoustooptic Bragg diffraction without the overmodulation mode, in which the efficiency of the Bragg order
attains its maximal value (close to 100%) upon an increase in the intensity of an acoustic wave and then remains practically
unchanged, is predicted theoretically and observed experimentally. The effect takes place in the case of considerable bending
of phase fronts of the acoustic field in the acoustooptic diffraction plane and attains its maximal value at a relatively
low frequency of sound, a small width of a piezoelectric transducer, strong acoustic anisotropy of the medium, and a large
distance between the light beam and the piezoelectric transducer.
Technical Physics 04/2012; 54(6):882-887. · 0.50 Impact Factor
ABSTRACT: The subject of investigation is multiple-beam Bragg diffraction of light, i.e., the formation of a highly effective multiple-beam
field representing a superposition of equidistant monochromatic acoustic waves with determinate phases and amplitudes using
a nonaxial TeO2 deflector. It is shown theoretically and experimentally that the anisotropic character of interaction considerably changes
the basic parameters of multiple-beam diffraction (compared with the isotropic case): the net diffraction efficiency grows
to 100%, and the frequency band expands noticeably. A modulator splitting the initial laser radiation into five beams of equal
intensity with a net efficiency approaching 100% is designed.
Technical Physics 05/2008; 53(6):752-756. · 0.50 Impact Factor
ABSTRACT: A set of equations describing acoustooptic diffraction of a light beam by acoustic waves of a fundamental frequency and its
harmonics in an isotropic medium is obtained. The possibility of suppressing higher diffraction orders by adding the second
or third harmonic to the fundamental monochromatic acoustic signal is theoretically justified. It is demonstrated that the
maximum degree of suppression decreases with an increase in the light beam divergence. Results of simulation are presented
for some particular cases of diffraction.
Acoustical Physics 01/2008; 54(5):597-602. · 0.70 Impact Factor
ABSTRACT: Multi-beam anisotropic acousto-optic Bragg diffraction of light by a multi-frequency acoustic signal in the geometry of the non-axial deflector based on TeO<sub>2</sub> is investigated. The significant increase of the anisotropic diffraction efficiency limit in compare with the isotropic one is predicted and experimentally verified. Also, the facility of remarkable growth of the outgoing spatial spectrum width and the allowed number of outgoing beams are established. The prototype of the 5 channels multiplexer has been developed with maximum efficiency close to 100%.
Ultrasonics Symposium, 2007. IEEE; 12/2007
Ultrasonics Symposium, 2005 IEEE; 10/2005