RESUMO
The observation and study of defects of single-crystal multicomponent optical material is necessary to determine the qualitative characteristics and optical properties of a material and to diagnose its manufacturing procedures. This paper utilizes the digital IR-holography to measure the geometrical parameters, shape, and location of defects as well as to characterize them. The paper illustrates the examples of physical, chemical, and optical inhomogeneities. Also, the paper presents the results of the study of dynamic processes in optical elements under the influence of laser radiation with high power density. The possibility of using the digital holographic technology to determine the dynamics of optical breakdown in the ZnGeP2 single crystal is illustrated, namely, to estimate the speed and time of breakdown development, which can be used to interpret the mechanisms of breakdown development.
RESUMO
The theoretical description of the field reconstructed from an in-line hologram of dispersed media is presented. The intensity distribution in the focal plane of a lens placed behind a hologram is analyzed. It is shown that two overlapped patterns are observing in this plane. The first pattern is entirely in accordance with the small-angle spectrum of radiation scattered by the ensemble of particles, and its view does not depend on the distances between the particles, the hologram, and the lens. The second pattern is made of Fresnel's rings and depends on the distance between the particles and the hologram. A statistical interpretation of the distribution of intensity in the focal plane of a lens is proposed. Experimental results and discussion are presented.
