About the Possibility of Linearization of Quadratic Cotton-Mouton Birefringence Change due to kH-Effect. Про можливості лінеаризації квадратичної магнітооптичної Котон-Мотонівської зміни двозаломлення за рахунок kH-ефекту. - ISSN 1609-1833

A possibility for appearance of the so-called kH-effect in crystals is analyzed, which originates from the light absorption, spatial dispersion and the influence of magnetic field. It is shown that the kH-effect can lead to linearization of the Cotton-Mouton effect. The coefficients of both the Cotton-Mouton (<$E(n sub 3 sup 3 beta sub 31 ~-~n sub 1 sup 3 beta sub 11 )~=~2,8~ times ~10 sup -15 ~ roman Oe sup -2}) and the kH-effect ( <$Edelta sub 1112 ~ symbol Г ~0,72~ times ~10 sup -20 ~ roman {m"/"Oe}>) are obtained for CdS crystals.

Acoustooptic Diffraction and Light Absorption in <$Eroman bold {Cs sub 2 BX sub 4 }> (B = Hg, Cd; X = Br, Cl) Crystals=Акустооптична дифракція та поглинання світла у кристалах <$Eroman bold {Cs sub 2 BX sub 4 }> (B = Hg, Cd; X = Br, Cl).. - ISSN 1609-1833

The acoustooptic (AO) efficiency of <$Eroman {Cs sub 2 HgBr sub 4 ,~Cs sub 2 HgCl sub 4 }> and <$Eroman {Cs sub 2 CdBr sub 4 }> crystals is experimentally studied. It is shown that <$Eroman {Cs sub 2 HgBr sub 4 }> and <$Eroman {Cs sub 2 CdBr sub 4 }> crystals are quite good AO materials. From the results for the absorption coefficients of <$Eroman {Cs sub 2 HgBr sub 4 }> and <$Eroman {Cs sub 2 CdBr sub 4 }> it follows that the latter crystals are transparent in a wide spectral range (up to the light wavelength of <$E25~ mu roman m>). The AO efficiency value for <$Eroman {Cs sub 2 HgCl sub 4 }> crystal reaches <$Eeta ~=~40~%> at the power P = 4W of electric drive signal of piezoelectric transducer.

Acoustooptic Diffraction in Borate Crystals. - ISSN 1609-1833

The efficiency of acoustooptic (AO) diffraction in (<$Ealpha - roman {BaB sub 2 O sub 4 }> and <$Eroman {Li sub 2 B sub 4 O sub 7 }> crystals is studied experimentally. The crystals are shown to be quite good AO materials. The efficiency of AO diffraction in (<$Ealpha - roman {BaB sub 2 O sub 4 }> reaches (=30 % at the electric signal power of P = 0,7W for the transverse acoustic wave and 15 % at the power of P = 0,56W for the longitudinal wave. The same parameter for <$Eroman {Li sub 2 B sub 4 O sub 7 }> reaches <$Eeta ~=~21~%> at P = 0,81W for the longitudinal acoustic wave.

Acoustooptic Interaction in Barium Beta-Borate Crystals. - ISSN 1609-1833

Basing on the measurements of photoelastic coefficients, acoustic waves velocities and the refractive indices, the possible geometries for acoustooptic interaction in <$Ebeta - roman {BaB sub 2 O sub 4 }> crystals have been analysed. It has been shown that the acoustooptic figureof merit achieves its maximum value when the transverse acoustic wave v13 with the velocity 817 m/s is propagated in YZ-plane. In this case <$EM sub 2 ~=~95,35~ times ~10 sup -15 ~ roman {s sup 3"/"kg}>.

Anisotropy of Laser-Induced Bulk Damage of Single Crystals. - ISSN 1609-1833

The regularities of laser-induced damage of anisotropic materials, such as <$Eroman LiNbO sub 3> and KDP dielectric single crystals, are experimentally studied. It is revealed that the shape of laser-induced damage in the dielectric crystals depends on the elastic symmetry of crystal and the propagation direction of the laser beam. When the beam propagates along the optic axis of crystals, the figures of the laser damage are six-path stars for <$Eroman LiNbO sub 3> and four-path ones for KDP crystals. For the direction parallel to X and Y axes in KDP crystal, the damage has initially cross-like configuration, with further splitting of Z-oriented crack into two cracks in the process of damage evolution, leading to transformation of orthogonal-type damage to a hexagonal-type one.

Appearance of Optical Vortex at Conical Refraction. Examples of <$Eroman bold {NaNO sub 2 }> and <$Eroman bold {YFeO sub 3 }> Crystals. - ISSN 1609-1833

In the present paper it is shown that effect of conical refraction is accompanied by a generation of vortex due to the existing singularities on the surfaces of phase and group velocities in biaxial crystals. This fact is confirmed experimentally by the studies of conical refraction in <$Eroman YFeO sub 3> and interference patterns in <$Eroman NaNO sub 2> crystals. The angle of external conical refraction in <$Eroman YFeO sub 3> crystals determined by us is equal to <$E4,2 symbol Р>.

Baric Changes in the Optical Indicatrix of TGS Crystals with L-threonine Admixture. - ISSN 1609-1833

The influence of uniaxial mechanical stresses, applied along the principal crystal-physical axes, on the principal values of birefringence Дni is studied for TGS crystals with 5 % L-threonine admixture. It is revealed that <$EDELTA n sub i> are quite sensitive to themechanical stresses. The baric coefficients <$Edel roman {T sub c } "/" del sigma sub { roman m }> for the phase transition temperature appear to be less than those for the pure TGS. Temperature dependences and dispersion of the piezooptic coefficients are calculated. The jump-like changes in all of the piezooptic coefficients occurring at the Curie temperature in the doped crystals are explained with the contributions of a secondary electrooptic effect.

Cavity Mirrors for He-Ne Lasers with Simultaneous Lasing at the Transitions with <$Ebold { lambda sub 0 ~=~0,6328~ mu roman m}> and <$Ebold { lambda sub 1 ~=~3,39~ mu roman m}>=Резонаторні дзеркала для He-Ne лазера з одночасною генерацією на переходах з <$Ebold { lambda sub 0 ~=~0,6328~ roman мкм}> і <$Ebold { lambda sub 1 ~=~3,39~ roman мкм}>. - ISSN 1609-1833

In this work the approach to designing and manufacturing the mirrors for optical cavities of the lasers with simultaneous generation at two different transitions is formulated. Using the model of equivalent layer, the structures of the mirrors for He-Ne lasers operating at the wavelengths of <$Elambda sub 0 ~=~0,6328~ mu roman m> and <$Elambda sub 1 ~=~3,39~ mu roman m> are described. The efficiency of use of the obtained mirrors in serial lasers is demonstrated.

Change of Optical Properties of Space under Gravitation Field. - ISSN 1609-1833

It is shown that, in the model of a flat 3D space, the time (i.e., the Hubble or the gravitation constant) plays a role of a spatial property. Gravitation field of spherical central mass does not lead to a lowering of symmetry of the space and appearance of anisotropy. In particular, the relations that describe the changes in the refractive indices of the space treated as an optical medium near the massive spherical body under the influence of its gravitation field have been derived.

Combined Piezoelectrooptic Effect in Rochelle Salt at the Phase Transition. - ISSN 1609-1833

The results of study of piezoelectrooptic (PEO) effect in the course of ferroelectric-ferroelastic phase transition in Rochelle salt crystals are presented. The coefficient of the combined effect is obtained from measurements of the changes in the electrooptic coefficients under the action of mechanical stress and the changes in the piezooptic coefficients under the action of electric field (or spontaneous polarization). It is shown experimentally that the values of both coefficients are the same, aspredicted by the theory. The temperature dependence of the coefficient of combined PEO effect is obtained. Its anomalous behaviour at the phase transition appears due to the dielectric permitivity anomaly. It is also demonstrated that the change in the piezooptic coefficients at the phase transition in Rochelle salt crystals may be satisfactorily explained as a result of linear and quadratic PEO effect induced by spontaneous polarization.

Comparison of the Blood Component Optical Transmission Spectra of White Rats with and without Ethanol Intoxication. - ISSN 1609-1833

In this report we present spectroscopic transmission studies of hemoglobin extracted from the vein blood of laboratory rats free of and exposed to ethanol intoxication, which are performed in order to analyze the relevant spectral differences. The animals were divided into the intoxicated group (IG) and the control group (CG). The results show a noticeable difference of the absorption/transmission spectra of hemoglobin extracted from the blood of these two groups. The difference in the absorption spectra is probably associated with the fact that the vein blood of ethanol-intoxicated animals includes more RHb than that of the CG. The deoxygenation process rate for the hemoglobin of intoxicated animals reaches a higher value and is quicker than that for the CG. It means that the affinity of the IG hemoglobin to oxygen is smaller than that for the CG. The minimum in the transmission spectra of hemoglobin with the dissolved cibacron blue colouring agent is shifted to a longer wavelength range (620 nm).The transmittance value for the IG is smaller than that for the CG, implying probably that the immunoglobulin G (IgG) in the IG possesses a more essential decomposition of its spatial structure, when compare with the CG. The changes in the transmission spectra of hemoglobin are detected after adding <$Eroman {H sub 2 O sub 2 }> and bromthymol blue, indicating the protein conformational changes for the IG animals.

Complex Degree of Mutual Polarization of Biotissue's Speckle-Images. - ISSN 1609-1833

The article is directed to studies for the statistics of coordinate distributions of the complex degree of mutual polarization (CDMP) characterising biotissues' images. Diagnostic possibilities of the 2D distributions of the images' CDMP correspondingto physiologically normal and degeneratively-dystrophically changed biological tissues are analysed.

Conjugated Polyaminoarenes as Electrochromic Layers for Non-Emissive Displays. - ISSN 1609-1833

Electrochromic properties of polyaminoarenes with different molecular structure, such as poly-o-aminophenol (POAP), poly-o-toluidine (POTI), poly-o-methoxyaniline (POMA) and polyaniline (PANI), are studied as potential materials for the three- and two-electrode construction of electrochromic devices.

Crystal Optical Properties of Inhomogeneous Plates and the Problems of Polarization Tomography of Photoelastic Materials. - ISSN 1609-1833

Using the Jones matrix formalism, crystal optical properties of inhomogeneous material consisting of a pile of weakly birefringent plates are analysed in relation to the cell model adopted in polarization tomography of 3D dielectric tensor field in photoelastic media. It is shown that the material manifests in general an "apparent" optical gyration caused by different orientations of the plates. Relations between the polarimetric parameters and the dielectric tensor components are ascertained for thecase of weak optical anisotropy.

Determination of 2D Stress Distribution in Semiconductor Glass <$Eroman bold {As sub 2 Se sub 3 }> with Infrared Imaging Polarimeter. - ISSN 1609-1833

In this paper the optical polarimetric method for determination of inhomogeneous 2D stress distribution in semiconductor samples is presented. The infrared imaging polarimeter is tested on the example of <$Eroman {As sub 2 Se sub 3 }> semiconductor glass possessing the induced inhomogeneous stresses. The reconstructed distribution of the shear stress tensor component <$Esigma sub 6> and the difference (<$Esigma sub 1 ~-~ sigma sub 2>) of the principal tensor components are in a satisfactory agreement with those predicted theoretically.

Dispersion of Refractive Indices in <$Eroman bold {Cs sub 2 CdBr sub 4 }> and <$Eroman bold {Cs sub 2 HgBr sub 4 }> Crystals. - ISSN 1609-1833

Dispersion of the refractive indices in <$Eroman {Cs sub 2 CdBr sub 4 }> and <$Eroman {Cs sub 2 HgBr sub 4 }> crystals has been experimentally obtained for the visible spectral range. The dispersion curves have been extrapolated towards the UV and IR ranges on the basis of single-term Sellmeier formula.

Doping-Induced Absorption in Polyphenylacetylene Films. - ISSN 1609-1833

The processes of donor and acceptor doping of polyphenylacetylene (PPA) films electrochemically obtained on transparent electrodes have been studied. It has been shown that donor n-doping of the PPA by lithium leads to formation of free charge carriers in the conjugated polymer chain, which cause a doping-induced absorption in the long-wave region. Under acceptor p-doping of the PPA films by iodine, the doping-induced optical absorption is observed in the short-wave region. It results from the complexes of charge transfer between the PPA and iodine.

Effect of Illumination on the Dielectric Properties of Lead Molibdate Crystals. - ISSN 1609-1833

The influence of light illumination on the dielectric properties of <$Eroman {PbMoO sub 4 }> crystals is studied. The increase of the permittivity under illumination is revealed. The optical excitation spectrum of the permittivity is practically the same as that of thefluorescence and photoconductivity. The results for dependences of this "photo-dielectric effect" (p.d.e.) on the temperature, the frequency of measuring electric field, the samples thickness and the light intensity are presented. They show a close relation of the p.d.e. to the point defects of crystalline lattice. A possible mechanism for the p.d.e. is suggested.

Electronic Bands Behaviour at Sinusoidal Potential Presence of Incommensurate Crystals. - ISSN 1609-1833

On the basis of solving the Schrodinger and Mathieu equations, for the case of crystal field perturbed by one-dimensional sinusoidal potential of the modulated phase in uniaxial ferroelectrics, it has been shown that the positions of electronic levelsare sensitive to the ratio of periods of the crystal field and the perturbation potential. Considering the energy states as prototypes of bands normalized by perturbation, one can come to the conclusion that the level of the states is the same as in the initial lattice, when the commensurate perturbation period is doubled. Incommensurate changes in the modulation parameter are shown to lead to modification of the distance between the energy levels or bands.

Electrooptic Effect in Non-Centrosymmetric <$Eroman bold {CsLiB sub 6 O sub 10 }> Borate Crystals. - ISSN 1609-1833

Electrooptic coefficient of <$Eroman {CsLiB sub 6 O sub 10 }> crystals has been experimentally determined as <$Er sub 63 ~=~3,3~ times ~10 sup -12 ~ roman {m"/"V}>. The half-wave voltage for <$Eroman {CsLiB sub 6 O sub 10 }> (<$EU sub { lambda "/"2 } ~=~26~ roman kV>) is three orders of magnitude larger than that of the known KDP crystals.