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A method of calculation is proposed and total energy losses in one round trip for lower EH1m, TE0m and TM0m modes are obtained numerically for diffraction mirror in the form of a circular diaphragm which placed inside a dielectric circular hollow waveguide. It is shown that the use of diffractive mirrors with large-scale irregularities in a dielectric waveguide resonator is the preferred among intracavity...
Theoretically on the basis of the vectorial Rayleigh-Sommerfeld theory and experimentally using terahertz radiation of the waveguide laser (λ = 0.4326 mm) the physical features of propagation and “moderate” or “sharp” focusing of laser beams of radiation are investigated in free space which described by modes of circular hollow dielectric waveguide with different spatial polarization.
An experimental sample of a waveguide CO2 laser with a quasi-uniform profile of the output radiation intensity is designed on the basis of a waveguide quasi-optical cavity of a new type comprising the generic confocal cavity with a nonuniform mirror and the hollow waveguide with the dimensions satisfying the conditions for self-imaging the quasi-uniform field. The surface of the mirror has the discrete...
Theoretical and experimental comparison of the divergence of TE01 mode and Gaussian beam can be concluded that the obtained analytical expressions in nonparaxial approximation correctly describe the propagation of waveguide modes in free space. Stable structure of the field for the symmetric waveguide modes in the terahertz range is observed at shorter distances, unlike the distances predicted by...
The method of calculation is proposed and coefficients of reflection and transmission of symmetric modes are obtained numerically for diffraction mirror in the form of a radial or circular diaphragms which placed inside a metal circular waveguide. The conditions of application of the polarization-selective mirrors for obtaining the modes with a given azimuthal or radial polarization in waveguide quasi-optical...
The influence of the curvature of the spherical mirror for metallic waveguide resonator of submillimeter laser (» = 0.4326 mm) on energy losses and the mode composition of radiation is investigated. It is shown that the presence of quadratic phase aberrations in the mirrors of the waveguide cavity with an increase of its Fresnel number at monotonically decreasing of the energy losses for fundamental...
In due time, Yuzhnoye SDO was a participant of the lunar program and many other projects, owing to which it currently possesses technologies and experience for development of integral components of space transportation systems that may be utilized in international programs aimed at the Moon development. Amongst them, one may specifically highlight the following three: •liquid-propellant booster based...
The method of obtaining of wave beams with a uniform intensity profile in the waveguide quasioptical resonator (WQR) is described. It is based on the self-imaging properties of multimode rectangular waveguides and using the nonuniform mirror with the discretely distributed absorbing or scattering sections. The theoretical model and calculation algorithm of characteristics of the low-loss Fourier-mode...
The method of the space Fourier-filtration for selective excitation of separated high-order modes in the metal waveguide quasioptical resonator with a high discrimination degree of undesirable modes is realized. Configurations of the phase-shifting mirrors for shaping of the high-order transverse modes in the laser resonators containing waveguides and open parts are proposed.
The method of a spatial Fourier filtration for selective excitation of separate higher types of oscillations with a high degree of discrimination of undesirable modes is proposed and realized. By the matrix method it is carried out a numerical study of characteristics of the lowest transverse modes for the metal resonator of the submillimeter laser from the geometrical sizes of mirrors and parameters...
This paper describes the phase conjugation method for producing non-Gaussian light beams with the given profile of intensity distribution in waveguide resonators. The existence of beams with super-Gaussian profile of intensity of a field in such resonators is confirmed theoretically and experimentally.
A description is given of a method of forming, in a waveguide quasi-optical resonator, non-Gaussian light beams with a uniform intensity distribution. The method is based on the coherent summation of transverse waveguide modes due to change by radius of curvature for one of mirrors. The theoretical model and calculation algorithm for characteristics of the basic mode with the uniform intensity distribution...
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