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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Structural deflections and optical performances of lightweight mirrors.

Cho, Myung Kyu January 1989 (has links)
A parametric design study of light weight mirror shapes with various support conditions was performed utilizing the finite element program NASTRAN. Improvements in the mirror performance were made based on the following design criteria: (1) minimization of the optical surface wavefront variations, (2) minimization of the self-weight directly related to cost of manufacturing, and (3) optimal location of support points. A pre-processor to automatically generate a finite element model for each mirror geometry was developed in order to obtain the structural deformations systematically. Additionally, a post-processor, which prepares an input data file for FRINGE (an optical computer code) was developed for generating the optical deflections that lead to the surface wavefront variations. Procedures and modeling techniques to achieve the optimum (the lightest and stiffest mirror shape due to self-weight) were addressed. Fundamental natural frequency analyses, for contoured back mirror shapes for a variety of support conditions, were performed and followed by comparisons of the results which were obtained from NASTRAN and a closed-form approximate solution. In addition, element validity and sensitivity studies were conducted to demonstrate the behavior of the element types provided in the NASTRAN program when used for optical applications. Scaling Laws for the evaluations of the optical performances and the fundamental frequencies were established.
2

ABSOLUTE MEASUREMENT OF RADIUS OF CURVATURE.

Londoño-Hartmann, Carmiña. January 1982 (has links)
No description available.
3

GRAVITY DEFLECTIONS AND SHAPE OPTIMIZATION FOR LIGHTWEIGHTED MIRRORS.

Iraninejad, Bijan. January 1982 (has links)
No description available.
4

Structural design of a large deformable primary mirror for a space telescope

Hansen, James G. R. January 1981 (has links)
No description available.

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