The matter of investigations    State-of-the-art investigations
Historical review Investigations in Acoustics Institute
Applied use Laboratory of optoacoustics

The matter of investigations

Optoacoustics is the field of scientific knowledge dealing with effects of sound excitation by laser pulse or intensity-modulated light beam. Acoustical pulse propagating from the area having absorbed light is one of the basic visualisations of the effect of interaction of laser radiation with a substance.

Historical review

Optoacoustical (OA) effect discovered by A. Bell in 1881 and also described in works of W. Roentgen and D. Tindal was forgotten for long shortly after. New stage of investigation of optoacoustical effect and possibilities of its application for analysis of condensed media began after creation of lasers. 1962 was memorable because it was the year when White in the USA and Prokhorov with co-workers in the USSR independently of each other discovered effective sound excitation in condensed medium under the influence of laser pulses. Those years, prospects of applications of this effect were quickly determined, in spite of absence of clear understanding of nature of these phenomena underlying such a transformation. Hydroacoustics is said to be one of possible important applications. Priority of patent for acoustical generator of Brewer and Rickhoff relates already to 1964. It is the very patent, which contains proposition to use area of focus of powerful laser beam as a pulse laser source of intensive sound oscillations with high coefficient of transformation of optical energy into sound one. Level of signal over 0.1 MPa achieved by authors let them to propose this source both for technological applications and for investigations of oceanic bottom. By this time results of both observations of effect and various applications assembled extensive bibliography.

Applied use

Investigations of optoacoustical effects are of fundamental and applied interest. For example, conformably to liquid media two problems are determined. To solve them pulse optoacoustical effect is applied. These are problems of complex express-diagnostics of various liquid samples and creation of powerful distantly active sound source for oceanographic, technological, surgical and others applications. For example, the fact that number of publications on this problem in journal for chemists "Analytical chemistry" exceeds similar one for fundamental issues "Ultrasonics" and Journal of the Acoustic Society of America is evidence of high applied potential of optoacoustics.

State-of-the-art investigations

Contemporary optoacoustics is fast developing field of scientific knowledge, attracting great number of specialists all over the world. Routinely, conferences on opto(photo)acoustics are conducted, conference digests and collective monographs on "Principles and Perspectives of Photothermal and Photoacoustic Phenomena" are issued. Scientific editions of different type readily publish articles on this topic. For specialists, students and dilettantes professor Zoltan Bozoki, Hungary maintains sending page in Internet to the address pa_and_pt@physx.u-szeged.hu.

Successes of optoacoustics owe scientists of ci-devant USSR. Regular investigations of fundamental problems of optoacoustics in our country were concordantly begun in 1973 by collectives under the direction of professors L. M. Lyamshev and K. A. Naugol'nykh (Acoustics Institute named after N. N. Andreev), professor F. V. Bounkin (Physical Institute named after P. N. Lebedev), professors S. A. Akhmanov and O. V. Roudenko (Moscow State University named after M. V. Lomonosov).

Abroad the most significant results in the field of optoacoustics were obtained in IBM Research Laboratory, Brown University, Max Plank Institute, University of Tokyo, High Technical school of Zurich and in others centres.

Investigations in Acoustics Institute

In Acoustics Institute works in the field of optoacoustics have been carried out since the beginning of 70s under the direction of professors L. M. Lyamshev, K. A. Naugol'nykh and S. V. Egerev in the frameworks of specially founded Laboratory of optoacoustics.