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The results of computer simulation of a precision position sensor based on the Foucault knife for automatic focusing of radiation during high-speed laser technological processes are presented, and the results of its implementation and testing at industrial enterprises as part of circular laser recording systems are presented. This sensor is built into laser complexes for microstructuring the surface of optical materials and makes it possible to determine their position with high resolution (the error does not exceed 0.1 µm). [ABSTRACT FROM AUTHOR]

The paper presents preliminary results of experiments designed to search for hyperbolic or H-fields, which, according to the theoretical representations developed in [1 - 15], should lead to a local modification of the flow of time. As a generator of the H-field, it is used a process of mechanical strike and as a detector, a highly stable quartz generator. The result of the influence of the H-field on the quartz generator has to be a modification of its oscillation parameters. In the experiment, it is discovered a shift of the power spectrum of oscillation of the quartz generator in the moment of the strike, in comparison with the spectrum in control, obtained under the same conditions, but without the strike. The theoretical estimates given in the paper for the acoustic, electromagnetic and gravitational wave mechanisms of influence of the strike on the oscillations of the quartz generator prove that these mechanisms cannot produce any experimentally observable spectrum shift, either from the qualitative or from the quantitative point of view. [ABSTRACT FROM AUTHOR]

Complex phosphates and arsenates of alkali metal and zirconium with NASICON and Sc(WO4)3 structures are fast ion conductors. In this context, double arsenates MZr2(AsO4)3, where M = Li, Na, K, Rb, and Cs, have been synthesised as powders through a precipitation method and investigated by Raman and infrared spectroscopy in combination with factor-group analysis to assign the bands. The stretching and bending vibrations of the AsO43- units and external modes, as well as the Zr4+ and M+ (Li-Cs) translations, have been determined for these compounds, which crystallised in the R3c (D3d6) and P1121/n (C2h5) space groups (LiZr2(AsO4)3). The correlations between the spectra and the nature of the M+ cation are revealed. Some external modes were identified by studying mass effects (Zr-Hf, Na-Cs). The bands for the symmetrical bending vibrations of the AsO43- units and some of the external modes shift towards higher wavenumbers with the increasing size of the alkaline cations due to the predominant direction of these vibrations and translations along the a axis; the M+ cation size increases as much as parameter a decreases. The differences observed in the vibrational spectra of the arsenates containing alkaline elements and zirconium with different space groups are caused by the reduced symmetry. [ABSTRACT FROM AUTHOR]

A precision laser pattern generator for writing arbitrary diffractive elements was developed as an alternative to Cartesian coordinate laser/electron-beam writers. This system allows for the fabrication of concentric continuous-relief and arbitrary binary patterns with minimum feature sizes of less than 0.6 microm and position accuracy of 0.1 microm over 300-mm substrates. Two resistless technologies of writing on chromium and on amorphous silicon films were developed and implemented. We investigated limit characteristics by writing special test structures. A 58-mm f/1.1 zone plate written directly is demonstrated at a lambda/50 rms wave-front error corresponding to a 0.06-microm pattern accuracy. Several examples of fabricated diffractive elements are presented.