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Calculation of radiative heat transfer in argon arc plasmas
Aubrecht, Vladimír
Radiative heat transfer is a significant energy exchange process in arc plasmas. In the paper, an approximate "Method of partial characteristics (MPC)" is used to evaluate radiation intensities, radiation fluxes and divergence of radiation fluxes in an arc plasmas of cylindrical symmetries at various plasma temperature profiles.
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Study of the Behaviour of Microparticle in the Standing Wave Trap
Ježek, Jan ; Jonáš, Alexandr ; Zemánek, Pavel ; Liška, M.
The basic behavior of microparticles placed in the Gaussian standing wave is studied theoretically and experimentally in this article. It is shown that the optical force depends periodically on the particle size and, as the consequence, the equilibrium object position is alternating between the standing wave antinodes and nodes. For certain particle sizes, the particle confinement is disabled. Experimental confirmation of the theoretical results is briefly discussed.
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Measurement of the Optical Trap Stiffness
Jákl, Petr ; Jonáš, Alexandr ; Zemánek, Pavel ; Liška, M.
An optical trap for dielectric microparticles is usually approximated by a parabolic potential well, whose profile is characterized by a single constant - trap stiffness. This stiffness can be estimated using several methods, including Fourier spectral analysis of the thermal noise of the trapped particle position, or method based on equipartition theorem. The principles of the trap calibration and experimental results are presented.
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Diffractive Optics: Analysis, Design and Fabrication of Diffractive Optical Elements
Fiala, P. ; Matějka, František ; Richter, I. ; Škereň, M.
This contribution presents results obtained in the field of diffractive optics, covering practically all aspects of the analysis, design and realization process of the diffractive optical elements (DOEs). As for the analysis, using the rigorous diffraction methods, we have recently been able to efficiently analyze various diffraction gratings. Concerning the synthesis, several design strategies have been studied and implemented for designing both binary and multi-level phase DOEs. Using the numerically computed designs, E-beam lithography technology has been chosen for fabricating both binary and multi-level phase DOEs, using the BS 600 e-beam lithographic facility at ISI AS CR. Finally, some typical examples of optical reconstructions are presented and discussed.
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