7. Optical methods for micro and nanoflows investigations
E.P. Domorackiy, T.N. Baybikova,
National Research University «Higher School of Economics», Russia, Moscow, Moscow University of Finance and Law, Russia, Moscow
Laser method of optoelectronic control of the sizes and shape of flying microobjects with their reconstruction by their impulse projective images
In the paper, a fast laser method of the geometrical optoelectronic differential control of threedimensional micro objects (MO) flow, which is based on the statistical dynamic few-views reconstruction of the sizes and shape of each MO with the usage of the basic characteristics of one triad of their impulse discrete two-dimensional projective images is under consideration. The squares of three mutually orthogonal two-dimensional projective images of MO and linear dimensions of its three one-dimensional projective images onto mutually orthogonal axes are chosen as the main basic characteristics. Impulse images of moving (flying) MO are formed by their flaring in the parallel rays from impulse laser sources of optical radiation and their simultaneous registration with the usage an optoelectronic position-sensitive video detector with memory, which works in the mode of separate image recording and reading. The spatial geometrical characteristics of dimensions for each MO are described as linear dimensions (overall dimension) and the average projected diameter (D) of a three-dimensional image of the reference ellipsoid that approximates each MO. The shape factor (K), which is used when describing the shape of MO, is specified by the ratio of the maximum and minimum overall dimensions (axis) of the approximating ellipsoid. The speed performance of the method of control under consideration is not less than 100 MO per second. Along with this the relative error of MO diameter control does not exceed 0,25 per cent (with the accuracy PD = 0,7 and K = 1,3 relative units), and the relative error of control of the MO shape factor is in the scope from 2,3 % (PK = 0,7 and K = 1,3 relative units) till 0,6% (with PK = 0,96 and K = 1,05 relative units).
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