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This research evaluates the optical properties of an inhomogeneous and non-paraxial system using a solar ball lens (SBL) as a new thermal solar concentrated collector. This evaluation is based on detecting a diacaustic curve in a straightforward and accurate manner, with the diagnostic relying on image processing as a computational tool using the MATLAB program rather than a complicated numerical analytic procedure. The circle of least confusion (CLC) of the (SBL), (Fluorinated ethylene propylene (FEP) polymer – water core), was calculated. Furthermore, the study evaluated the maximum geometrical concentration ratio (G C) of refracted solar radiation that can be captured by a receiver of the (SBL). Without energy losses due to spherical aberration, the (G C) ratio was (14.10) at (h/r) ratio, circular aperture radius to ball radius, around (0.6). The investigation also revealed an aplanatic point for preventing the development of optical envelope inside the solar ball lens at (h/r) equal to 0.8638, as well as a maximum (h/r) value of 0.7351 for collecting solar radiation.

Iodine-doped polythiophene thin films are prepared by aerosol assisted plasma jet polymerization at atmospheric pressure and room temperature. The doping of iodine was carried out in situ by employing iodine crystals in thiophene monomer by weight mixing ratios of 1%, 3%, 5% and 7%. The chemical composition analyses of pure and iodine-doped and heat-treated polythiophene thin films are carried out by FTIR spectroscopy studies. The optical band gaps of the films are evaluated from absorption spectrum studies. Direct transition energy gaps are determined from Tauc plots. The structural changes of polythiophene upon doping and the reduction of optical band gap are explained on the basis of the results obtained from FTIR spectroscopy, UV–VIS absorption studies, X-ray diffraction and atomic force microscope (AFM) analysis. The energy band gap will be different according to the concentration of polythiophene iodine. It can be concluded that iodine-doped polythiophene thin films can be prepare by aerosol assisted plasma jet polymerization and control the optical energy band gap regulars by controlling the thiophene -iodine weight mixing ratios.

Introduction: It is well known that the biggest problem facing the utilizing of solar cell Panels in Baghdad is the unpredictable dusty weather through the days of year. This big problem is not easy to overcome due to the frequent dust accumulations and the high cost of cleaning and other maintenance problems. Dust problems are increasing due to global warming. In Baghdad city, where solar radiation is intense and available almost throughout the year, Deposition of dust on the panels could severely minimize solar-to power output efficiency. There are many methods for dust removing from surfaces like the natural dust removal of wind, mechanical dust removing, super-hydrophobic on solar panel surface, and the electrostatic method which is adopted in this work. The dust particles will be charged statistically by rolling on the surface of the solar panels they will have the same electric charge and the electrostatic forces between them are repulsion. Hence, the dust particles will float away from the solar panels. Materials and Methods: A self-charging transparent conductive glass is prepared by spraying a thin film (141 nm thickness) of a Tin dioxide (SnO2) solution on a glass substrate (12x12 cm2). The dust shield is connected to an electronic charging circuit. The shield is located on the top of a silicon solar cell. The novel idea is that the shield is electrically supplied by the solar cell itself whereas D.C. current from the solar cell itself is used to charge the conductive glass, which is located on the top surface of the cell. Results and Discussion: A test was done for dust removing from a Silicon solar cell by electrostatic repulsion method, considering matching the spectral response region of the Siliconsolar cells with the film transmittance spectral region (400 -700 nm). The transmittance value is between (92 – 95)% and results are compared withan identical reference solar cell. Results show a good response as the calculated clearing factor value increases due to the cell efficiency increment.Also, the clearing factor is discussed as a function of outdoor temperature to show a direct proportionality, while the environmental humidity showed an inverse proportionality. Conclusions: A self-cleaning method for a solar cell is successfully introduced via a conductive glass. tests were carried outdoor in Baghdad city. Results showed that there is a direct proportionality between both: the clearing factor and the efficiency gain with the ambient temperature. The ambient humidity showed indirect proportionality with system efficiency (clearing factor and efficiency gain show reduction as the humidity percentage increases).