The study of sub-surface damage distributions during grinding process on different abrasion materials

Ching-Hsiang Kuo; Chien-Yao Huang; Zong-Ru Yu; Shyu-Cheng Shu; Keng-Shou Chang; Wei-Yao Hsu

doi:10.1117/12.2279673

16 October 2017 The study of sub-surface damage distributions during grinding process on different abrasion materials

Ching-Hsiang Kuo, Chien-Yao Huang, Zong-Ru Yu, Shyu-Cheng Shu, Keng-Shou Chang, Wei-Yao Hsu

Proceedings Volume 10448, Optifab 2017; 1044823 (2017) https://doi.org/10.1117/12.2279673
Event: SPIE Optifab, 2017, Rochester, New York, United States

Abstract

The grinding process is the primary technology for curvature generation (CG) on glass optics. The higher material removal rate (MRR) leads to deeper sub-surface damage (SSD) on lens surface. The SSD must be removed by following lapping and polishing processes to ensure the lens quality. However, these are not an easy and an efficient process to remove the SSD from ground surface directly for aspheric surfaces with tens or hundreds microns departure from bestfit- sphere (BFS). An efficient fabrication procedure for large aspheric departure on glass materials must be considered. We propose 3-step fabrication procedures for aspheric surface with larger departure. 1st step is to generate a specific aspheric surface with depth less than 10 μm of SSD residual. 2nd step is to remove SSD and keep the aspheric form by using Zeeko polisher with higher MRR pad. Final step is to figure and finish the aspheric surface by using QED MRF machine. In this study, we focus on the 1st step to investigate the residual depth of SSD after grinding process on different abrasion materials. The materials of tested part are fused silica, S-NPH2, and S-PHM52. The cross grinding would be configured and depth of SSD/surface roughness would be evaluated in this study. The characteristic of SSD could be observed after etching by confocal microscope. The experimental results show the depth of SSD below 31.1 μm with #400 grinding wheel. And the near 10 μm depth of SSD would be achieved with #1,000 grinding wheel. It means the aspherization polishing on large parts with large departure from best fit sphere would be replaced. The fabrication of large aspheric part would be efficient.

Citation Download Citation

Ching-Hsiang Kuo, Chien-Yao Huang, Zong-Ru Yu, Shyu-Cheng Shu, Keng-Shou Chang, and Wei-Yao Hsu "The study of sub-surface damage distributions during grinding process on different abrasion materials", Proc. SPIE 10448, Optifab 2017, 1044823 (16 October 2017); https://doi.org/10.1117/12.2279673

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available