以模擬退火法架構之多波長繞射元件研製

• Main Authors: Kuang - Hung Fu, 傅光弘
• Other Authors: Yi - Bin Lu
• Format: Others
• Language: zh-TW
• Published: 2002
• Online Access: http://ndltd.ncl.edu.tw/handle/30659060644845111347

碩士 === 國防大學中正理工學院 === 電子工程研究所 === 90 === In this thesis, based on the optical diffraction theorem, we use the simulated annealing (SA) technology to design optimal multi-wavelength diffractive optical elements (DOEs). The optimization algorithm is designed by combining the iterative discrete on-axis encoding method (IDO), with the fractional Fourier transform theorem. The cost function we used is based on the concept of “norm” measure, which is commonly used to solve the image processing problems. Also, the weighting factors of the cost function are properly adjusted during the simulation process. The design of a Fraunhofer DOE have to face the disadvantages of fixed focal-plane imaging distance and symmetric imaging phenomenon of 2-level phase. In this work, we derive and use the two-dimensional discrete fractional Fourier transform ( ) provided by a Lohmann’s Type II optical system, which can simplify the design complexity of a Fresnel-domain DOEs, to design diffraction optics in variable distances. Finally, we use Matlab software to design an automatic user interface, and apply three standards, efficiency( ), dynamic range(DR) and signal to noise ratio(SNR) to examine the design performance of DOEs. Besides, we design a data transform program between the phase pattern of matlab and the drawing exchange format (DXF) of AutoCAD R14 software. Those files are used to generate masks for fabricating DOEs. The analysis and simulated results are shown in the end of this thesis.