천체망원경용 비구면 반사경 표면조도 향상을 위한 최적연삭변수 수치결정모델

• Published in: Journal of astronomy and space sciences Vol. 22; no. 1; pp. 13 - 20
• Main Authors: 한정열, 김석환, 김건희, 한인우, 양순철, Han, Jeong-Yeol, Kim, Sug-Whan, Kim, Geon-Hee, Han, In-Woo, Yang, Sun-Choel
• Format: Journal Article
• Language: Korean
• Published: 한국우주과학회 01.03.2005
• Subjects: 천문학; grinding optimization process; astronomical telescopes; surface roughness; aspheric mirrors
• ISSN: 2093-5587; 2093-1409

Bound abrasive grinding is used for the initial fabrication phase of the precision aspheric mirrors for both space and ground based astronomical telescopes. We developed a new grinding optimization process that determines the input grinding variables for the target surface roughness, checks the grinding error magnitude in resulting surface roughnesses, and minimizes the required machining time. Using the machining data collected from the previous grinding runs and subsequently fed into the multi-variable regression engine, the process has the evolving controllability that suggests the optimum set of grinding variables for each target surface roughness. The process model was then used for ten grinding experiments that resulted in the grinding accuracy of =-0.906 ± 3.38(sigma) nm (Ra) for the target surface roughnesses of Zerodur substrate ranging from 96.1 nm (Ra) to 65.0 nm (Ra). The results imply that the quantitative process optimization technique developed in this study minimizes the machining time and offers the nanometric surface roughness controllability superior to the traditional, qualitative, craftsman based grinding process for the astronomical optical surfaces. KCI Citation Count: 0