Versions of opto-elektronic processors have been suggested 1nrecent years, which can perform algebraic vector and matrix operations and realise pipeline and parallel processing algorithms. The paper presents the results of studies connected with the development of matrix processors have be.en carried out at the Institute of Automation and Electror metry since 1972. In 1 1975 a parallel version of optical triple matrix product pro- cessor was developed" The new optical system for parallel computing of three N x N matrices product D=BAC is analysed in detail.
An analysis of measurement errors of distance to the surface with narrow scattering indicatrix (mirror surface) by laser triangulation is given. We consider two types of sensors: with output plane orthogonal to the optical axis, and with tilted one (corresponding to the Scheimpflug principle). The conditions of Scheimpflug principle applicability for mirror surface testing are determined. We have shown, that at a certain ratio of parameters of optical system of the sensor to the probing light beam, the sensor with orthogonal plane of photoregistration can provide a smaller level of measurement errors than sensor with tilted output plane, despite the presence of defocusing. These advantages remain valid also at small surface tilts.
Two approaches to measurement of melt level in crucible are analyzed: the traditional one based on the use of laser triangulation sensor and the proposed method based on the use of noncoherent passive binocular sensor permitting to measure simultaneously both the melt level and the diameter of the crystal during the crystal growth. The limitations of these approaches are analysed. Estimates of metrological characteristics (systematic measurement errors and effective range) depending on the level of melt, its angular velocity and the distance of measurement zone from the centre of rotation are given. The requirements to the algorithms of digital signal processing, which should take into account the peculiarities of laser beam reflection from a non-stationary dynamic surface, are formulated. Possible sources of measurement errors are discussed, and results of such binocular sensor simulation that allow estimating its metrological characteristics for different values of system parameters are produced.
A description of machine sight system developed at IA&E of the Siberian Branch of RAS intended for the control of crystals cultivation process is given. The work of the system is based on digital processing of optical signals (images) registered by digital video cameras with linear photoreceivers. The algorithms of processing are developed which secure receipt of the melting level estimations, diameter of a crystal, width of the zone of meniscus. The metrological characteristics of system are given; the results of its testing and perspective variants of realization are analyzed.
The analysis of measurement errors of distance up to a mirror surface by laser triangulation is given. We consider the two types of sensors: with output plane, orthogonal to the optical axis, and with tilted one (corresponding to the Scheimpflug principle). The conditions of Scheimpflug principle applicability for mirror surface testing are determined. We have shown that at the certain ratio between parameters of optical system of the sensor and the probing light beam, the sensor with orthogonal plane of photoregistration can provide smaller level of measurement errors, than sensor with tilted plane, despite the presence of defocusing.
Problems of active coherent triangulation sensor applicability to non-stationary reflective 3D surface sensing are considered. As is shown in the paper, the accuracy of a sensor is connected not only with the resolution along the range and field of view, but also with the triangulation angle and direction of the normal to the surface, and with defocusing and aperture limitations of the optical system. Moreover, the processing algorithms of light distributions and statistical analysis of measured data are very important. The conditions for undistorted surface reproduction are defined. In the case of violation of such conditions only statistical evaluations of basic surface parameters are possible.
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