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

2021 ◽  
pp. 2463-2473
Author(s):  
Raaid Noffi Hassan ◽  
Huda Shaker Ali ◽  
Wafaa Hikmat Wadee
Keyword(s):  
Wave Front ◽  
Adaptive Optics ◽  
Optical System ◽  
Solar Surface ◽  
Phase Error ◽  
Circular Aperture ◽  
Initial State ◽  
Optical Aberrations ◽  
Wave Aberration ◽  
Aperture Function

     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.

scholarly journals Adaptive Optics for Visual Simulation

ISRN Optics ◽  
2012 ◽  
Vol 2012 ◽  
pp. 1-13 ◽  
Author(s):  
Enrique Josua Fernández
Keyword(s):  
Adaptive Optics ◽  
Optical System ◽  
State Of The Art ◽  
Neural Adaptation ◽  
Current Paper ◽  
Visual Simulation ◽  
Optical Aberrations ◽  
Current State ◽  
Ocular Aberrations ◽  
Visual Testing

A revision of the current state-of-the-art adaptive optics technology for visual sciences is provided. The human eye, as an optical system able to generate images onto the retina, exhibits optical aberrations. Those are continuously changing with time, and they are different for every subject. Adaptive optics is the technology permitting the manipulation of the aberrations, and eventually their correction. Across the different applications of adaptive optics, the current paper focuses on visual simulation. These systems are capable of manipulating the ocular aberrations and simultaneous visual testing though the modified aberrations on real eyes. Some applications of the visual simulators presented in this work are the study of the neural adaptation to the aberrations, the influence of aberrations on accommodation, and the recent development of binocular adaptive optics visual simulators allowing the study of stereopsis.

A New Design of Large Stroke Micro-Deformable Mirror Actuated by Electrostatic Repulsive Force

2008 ◽  
Author(s):  
Fangrong Hu ◽  
Jun Yao ◽  
Chuankai Qiu ◽  
Dajia Wang
Keyword(s):  
Electric Field ◽  
Resonant Frequency ◽  
Adaptive Optics ◽  
Bottom Electrode ◽  
Sacrificial Layer ◽  
Electrostatic Force ◽  
Repulsive Force ◽  
Deformable Mirror ◽  
Optical Aberrations ◽  
Out Of Plane

In this paper, a MEMS mirror actuated by an electrostatic repulsive force has been proposed and analyzed. The mirror consists of four U-shape springs, a fixed bottom electrode and a movable top electrode, there are many comb fingers on the edges of both electrodes. When the voltage is applied to the top and bottom electrodes, an asymmetric electric field is generated to the top movable fingers and springs, thus a net electrostatic force is produced to move the top plate out of plane. This designed micro-mirror is different from conventional MDM based on electrostatic-attractive-force, which is restricted by one-third thickness of the sacrificial layer for the pull-in phenomenon. The characteristic of this MDM has been analyzed, the result shows that the resonant frequency of the first mode is 8 kHz, and the stroke reaches 10μm at 200V, a MDM with large strokes can be realized for the application of adaptive optics in optical aberrations correction.

Development of a curvature wave-front sensor for the GUIELOA adaptive optics system

2006 ◽  
Author(s):  
Oscar Chapa ◽  
Salvador Cuevas ◽  
Beatriz Sánchez ◽  
Jordi Cantó ◽  
Héctor Mendoza
Keyword(s):  
Wave Front ◽  
Adaptive Optics ◽  
Adaptive Optics System

scholarly journals Space Variant PSF – Deconvolution of Wide-Field Astronomical Images

10.14311/1023 ◽  
2008 ◽  
Vol 48 (3) ◽  
Author(s):  
M. Řeřábek
Keyword(s):  
Optical System ◽  
Imaging System ◽  
Real Data ◽  
Wavefront Aberration ◽  
Wide Field ◽  
Optical Aberrations ◽  
Optical Aberration ◽  
Transfer Characteristics ◽  
Astronomical Images ◽  
Space Variant

The properties of UWFC (Ultra Wide-Field Camera) astronomical systems along with specific visual data in astronomical images contribute to a comprehensive evaluation of the acquired image data. These systems contain many different kinds of optical aberrations which have a negatively effect on image quality and imaging system transfer characteristics, and reduce the precision of astronomical measurement. It is very important to figure two main questions out. At first: In which astrometric depend on optical aberrations? And at second: How optical aberrations affect the transfer characteristics of the whole optical system. If we define the PSF (Point Spread Function) [2] of an optical system, we can use some suitable methods for restoring the original image. Optical aberration models for LSI/LSV (Linear Space Invariant/Variant) [2] systems are presented in this paper. These models are based on Seidel and Zernike approximating polynomials [1]. Optical aberration models serve as suitable tool for estimating and fitting the wavefront aberration of a real optical system. Real data from the BOOTES (Burst Observer and Optical Transient Exploring System) experiment is used for our simulations. Problems related to UWFC imaging systems, especially a restoration method in the presence of space variant PSF are described in this paper. A model of the space variant imaging system and partially of the space variant optical system has been implemented in MATLAB. The “brute force” method has been used for restoration of the testing images. The results of different deconvolution algorithms are demonstrated in this paper. This approach could help to improve the precision of astronomic measurements. 

Analysis of Adaptive Optics Techniques without a Wave-Front Sensor and Its Application in Atmospheric Laser Communications

2008 ◽  
Vol 35 (5) ◽  
pp. 680-684
Author(s):  
杨慧珍 Yang Huizhen ◽  
蔡冬梅 Cai Dongmei ◽  
陈波 Chen Bo ◽  
李新阳 Li Xinyang ◽  
姜文汉 Jiang Wenhan
Keyword(s):  
Wave Front ◽  
Adaptive Optics ◽  
Laser Communications
Sign in / Sign up

Export Citation Format

Share Document