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Computer Simulation for the Effects of Optical Aberrations on Solar Images Using Karhunen-Loeve polynomials

     Numerical simulations were carried out to evaluate the effects of different aberrations modes on the performance of optical system, when observing and imaging the solar surface. Karhunen-Loeve aberrations modes were simulated as a wave front error in the aperture function of the optical system. To identify and apply the appropriate rectification that removes or reduces various types of aberration, their attribute must be firstly determined and quantitatively described. Wave aberration function is well suitable for this purpose because it fully characterizes the progressive effect of the optical system on the wave front passing through the aperture. The Karhunen-Loeve polynomials for circular aperture were used to describe wave front deviations and to predict the initial state of adaptive optics corrections. The results showed that increasing the aberration modes causes an increase in the blurring of the observed image. Also, we conclude that the optical phase error is increased significantly when aperture’s radii are increased.

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Publication Date
Sun Jan 16 2022
Journal Name
Iraqi Journal Of Science
Simulations of Four Types of Optical Aberrations using Zernik Polynomials

In this paper, a computer simulation is implemented to generate of an optical aberration by means of Zernike polynomials. Defocus, astigmatism, coma, and spherical Zernike aberrations were simulated in a subroutine using MATLAB function and applied as a phase error in the aperture function of an imaging system. The studying demonstrated that the Point Spread Function (PSF) and Modulation Transfer Function (MTF) have been affected by these optical aberrations. Areas under MTF for different radii of the aperture of imaging system have been computed to assess the quality and efficiency of optical imaging systems. Phase conjugation of these types aberration has been utilized in order to correct a distorted wavefront. The results showed that

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Publication Date
Tue Jan 01 2013
Journal Name
Iraqi Journal Of Physics
Describing the Wavefront Aberrations of the Hexagonal Aperture Using Modified Zernike Polynomials

n Segmented Optical Telescope (NGST) with hexagonal segment of spherical primary mirror can provide a 3 arc minutes field of view. Extremely Large Telescopes (ELT) in the 100m dimension would have such unprecedented scientific effectiveness that their construction would constitute a milestone comparable to that of the invention of the telescope itself and provide a truly revolutionary insight into the universe. The scientific case and the conceptual feasibility of giant filled aperture telescopes was our interested. Investigating the requirements of these imply for possible technical options in the case of a 100m telescope. For this telescope the considerable interest is the correction of the optical aberrations for the coming wavefront, th

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Publication Date
Sat Dec 30 2023
Journal Name
Iraqi Journal Of Science
Describing the Wavefront Aberrations of the Hexagonal Aperture Using Modified Zernike Polynomials

The concept of the optical telescope is the primary mirror design, the Next Generation Segmented Optical Telescope (NGST) with hexagonal segment of spherical primary mirror can provide a 3 arc minutes field of view. Extremely Large Telescopes (ELT) in the 100m dimension would have such unprecedented scientific effectiveness that their construction would constitute a milestone comparable to that of the invention of the telescope itself and provide a truly revolutionary insight into the universe. The scientific case and the conceptual feasibility of giant filled aperture telescopes was our interested. Investigating the requirements of these imply for possible technical options in the case of a 100m telescope. For this telescope the conside

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Publication Date
Sat Dec 31 2022
Journal Name
Pakistan Journal Of Medical And Health Sciences
A Computer Simulation of Hubble Telescope Including Eyepiece Nano- Sensors to Increase Optical Efficiency

The Hubble telescope is characterized by the accuracy of the image formed in it, as a result of the fact that the surrounding environment is free of optical pollutants. Such as atmospheric gases and dust, in addition to light pollution emanating from industrial and natural light sources on the earth's surface. The Hubble telescope has a relatively large objective lens that provides appropriate light to enter the telescope to get a good image. Because of the nature of astronomical observation, which requires sufficient light intensity emanating from celestial objects (galaxies, stars, planets, etc.). The Hubble telescope is classified as type of the Cassegrain reflecting telescopes, which gives it the advantage of eliminating chromat

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Publication Date
Fri Sep 30 2022
Journal Name
Iraqi Journal Of Science
Computer Vision of Optimal Geometric Concentration Ratio for the Solar Ball Lens

      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

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Publication Date
Mon May 15 2023
Journal Name
Iraqi Journal Of Science
Computer Generation of Low Light-Level Images

As result of exposure in low light-level are images with only a small number of
photons. Only the pixels in which arrive the photopulse have an intensity value
different from zero. This paper presents an easy and fast procedure for simulating
low light-level images by taking a standard well illuminated image as a reference.
The images so obtained are composed by a few illuminated pixels on a dark
background. When the number of illuminated pixels is less than 0.01% of the total
pixels number it is difficult to identify the original object.

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Publication Date
Wed Jun 01 2016
Journal Name
Journal Of Engineering
Experimental and Simulation for the Effect of Partial Shading on Solar Panel Performance

Partial shading is one of the problems that affects the power production and the efficiency of photovoltaic module. A series of experimental work have been done of partial shading of   monocrystalline PV module; 50W, Isc: 3.1A, Voc: 22V with 36 cells in series is achieved. Non-linear power output responses of the module are observed by applying various cases of partial shading (vertical and horizontal shading of solar cells in the module). Shading a single cell (corner cell) has the greatest impact on output energy. Horizontal shading or vertical shading reduced the power from 41W to 18W at constant solar radiation 1000W/m2 and steady state condition. Vertical blocking a column

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Publication Date
Mon Jun 01 2015
Journal Name
Iraqi Journal Of Science
Simulation of Solar Coronal Magnetic Field Using Potential Field Model

In this paper, 3D simulation of the global coronal magnetic field, which use observed line of sight component of the photosphere magnetic field from (MDI/SOHO) was carried out using potential field model. The obtained results, improved the theoretical models of the coronal magnetic field, which represent a suitable lower boundary conditions (Bx, By, Bz) at the base of the linear force-free and nonlinear force free models, provides a less computationally expensive method than other models. Generally, very high speed computer and special configuration is needed to solve such problem as well as the problem of viewing the streamline of the magnetic field. For high accuracy special mathematical treatment was adopted to solve the computation comp

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Publication Date
Mon Jun 01 2020
Journal Name
Test Engineering & Management
The Effects of Annealing on SnSe Thin Films for Solar Cells Applications

The structure, optical, and electrical properties of SnSe and its application as photovoltaic device has been reported widely. The reasons for interest in SnSe due to the magnificent optoelectronic properties with other encouraging properties. The most applications that in this area are PV devices and batteries. In this study tin selenide structure, optical properties and surface morphology were investigated and studies. Thin-film of SnSe were deposit on p-Si substrates to establish a junction as solar cells. Different annealing temperatures (as prepared, 125,200, 275) °C effects on SnSe thin films were investigated. The structure properties of SnSe was studied through X-ray diffraction, and the results appears the increasing of the peaks

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Publication Date
Wed May 01 2019
Journal Name
Iraqi Journal Of Science
Optical Images Fusion Based on Linear Interpolation Methods

Merging images is one of the most important technologies in remote sensing applications and geographic information systems. In this study, a simulation process using a camera for fused images by using resizing image for interpolation methods (nearest, bilinear and bicubic). Statistical techniques have been used as an efficient merging technique in the images integration process employing different models namely Local Mean Matching (LMM) and Regression Variable Substitution (RVS), and apply spatial frequency techniques include high pass filter additive method (HPFA).  Thus, in the current research, statistical measures have been used to check the quality of the merged images. This has been carried out by calculating the correlation a

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