Physical, Thermal and Biological Properties of Yellow Dyes with Two Azodiphenylether Groups of Anthracene

Two yellow bis-azo dyes containing anthracene and two azodiphenylether groups (BPA and BTA) were prepared, and an extensive investigation of their physical, thermal and biological properties was carried out. The chemical structure was confirmed by the FTIR spectra, while from the UV–Vis spectra, the quantum efficiency of the laser fluorescence at the 476.5 nm was determined to be 0.33 (BPA) and 0.50 (BTA). The possible transitions between the energy levels of the electrons of the chemical elements were established, identifying the energies and the electronic configurations of the levels of transition. Both crystals are anisotropic, the optical phenomenon of double refraction of polarized light (birefringence) taking place. Images of maximum illumination and extinction were recorded when the crystals of the bis-azo compounds rotated by 90° each, which confirms their birefringence. A morphologic study of the thin films deposited onto glass surfaces was performed, proving the good adhesion of both dyes. By thermal analysis and calorimetry, the melting temperatures were determined (~224–225 °C for both of them), as well as their decomposition pathways and thermal effects (enthalpy variations during undergoing processes); thus, good thermal stability was exhibited. The interaction of the two compounds with collagen in the suede was studied, as well as their antioxidant activity, advocating for good chemical stability and potential to be safely used as coloring agents in the food industry.

POLARIZATION MODE DISPERSION COMPENSATOR BASED ON ANISOTROPIC OPTICAL FIBER

In this paper, a new method of polarization mode dispersion (PMD), which can significantly limit the speed and range of transmission of fiber optic transmission systems (FOTS), compensation was developed and analyzed. In contrast to the existing types of PMD compensators, in which the optical fiber is subjected to mechanical stresses to create a photoelastic anisotropy, in this work the use of alternative method of creating photoelasticity in optical fiber (OF) by creating a helical ordered rotation of the glass microstructure (ORMG) is proposed. The helical orientation of the microstructure of the OF glass is achieved by acting on the fiber in the process of manufacture (drawing), when it is in a hot state, electromagnetic field, the power lines of which are directed in a circle. I am not sure what this sentence is trying to say. The result is an asymmetry of the dielectric constant of the fiber glass material and therefore the anisotropy of the optical properties. When the optical signal propagates in such OF, there is a double refraction, which is the cause of artificial PMD in the compensator fiber. Compensation is achieved by performing the equality of the modulus and the sign-opposite between the linear path PMD and the PMD of the anisotropic OF with the ORMG. The expression of the calculation of the PMD of the compensator, which depends on the rotation step of the microstructure of the glass, the chemical composition of the OF, the length of the line, the width of the radiation spectrum and the wavelength of the optical signal, and the optical characteristics of the OF, is analyzed, as well as the spectral dependence of polarization mode dispersion for different chemical compositions of the OF. The expression of determining the length of the OF with the ORMG is presented to compensate for the set value of the PMD in the line. The results of the studies made it possible to determine the lengths of the segments of OF with ORMG, which will provide partial or complete compensation of PMD over a wide range of wavelengths and create passive compensators for dispersion.

Birefrince Characteristics of an Optical Element

Phase difference variation in uniaxial crystal is investigated for varying thickness. Using double refraction property and optic axis method leads to the intensity measurement. The periphery example got when a unique (or focalized) shaft experiences an example of birefringent gem between two polarizers contains data which is intrinsic of the crystalline example under examination.

The measurement of the vertical relief on metal-graphic microscopes of production of OJC «Optoelectronic systems»

The possibilities of measuring the depth of the surface relief on metallographic microscopes manufactured by OJSC «Optoelectronic systems» are illustrated. For the microscopes MI-1 and MICRO-200 a technique for determining the height of the relief is considered, which is based on the relationship between the angle of rotation of the drum tincture of precise focus and vertical movement of the object table. Examples of crater depth measurements after exposure to laser radiation on a metal surface are given. For MI-1 and MICRO-200 microscopes, the depth of the well was determined as 99.36 and 99.8 µm, respectively, which is consistent with the profilometer data (~100 µm). For a plane-parallel quartz plate, the measurement results were 0.435 µm when determined microscopically, as well as the object-micrometer. The possibility of determining the thickness of titanium nitride coatings by differential interference contrast is considered. The method allows the determination of the thickness of the difference in interference colors, if the image areas are at different heights. The thickness of the coating can be estimated using a nomogram of double refraction.

Stokes’s Optics 1

The purpose of this chapter and the following one is to explore and explain the rich diversity of Stokes’s contributions to physical optics in Cambridge and world contexts. He triggered debates and inspired friends through his semi-private speculations on the nature and motion of the ether in stellar aberration, double refraction, and optical rotation. He discussed deep-seated analogies between hydrodynamics and optics. He consolidated the fundamental laws of wave optics through mathematically sophisticated theories of interference, including Newton’s rings; diffraction, for which he provided a dynamical theory; and polarization. His theoretical achievements were backed up by carefully designed and extremely precise experiments.