Abstract

We present a new, to the best of our knowledge, experimental method for assessing sub-micron level subsurface damage (SSD) on optical glass. The method correlates surface characteristics such as the fracture toughness and Young’s modulus via nanoindentation with the penetration depth into the tested surfaces at different overall penetration depths, as revealed by magnetorheological finishing spotting techniques. Our results on ground surfaces suggest that low surface roughness does not necessarily imply the absence of SSD. We also compared SSD on surfaces processed by deterministic microgrinding and femtosecond (fs) laser polishing. The fs-laser polished surfaces revealed no detectable SSD, thus establishing the feasibility of fs-laser polishing for precision optical manufacturing.

© 2023 Optica Publishing Group

Subsurface damage in some single crystalline optical materials

Joseph A. Randi, John C. Lambropoulos, and Stephen D. Jacobs
Appl. Opt. 44(12) 2241-2249 (2005)

Subsurface damage and microstructure development in precision microground hard ceramics using magnetorheological finishing spots

Shai N. Shafrir, John C. Lambropoulos, and Stephen D. Jacobs
Appl. Opt. 46(22) 5500-5515 (2007)

Surface microroughness of optical glasses under deterministic microgrinding

John C. Lambropoulos, Tong Fang, Paul D. Funkenbusch, Stephen D. Jacobs, Michael J. Cumbo, and Donald Golini
Appl. Opt. 35(22) 4448-4462 (1996)

Loose abrasive lapping hardness of optical glasses and its interpretation

John C. Lambropoulos, Su Xu, and Tong Fang
Appl. Opt. 36(7) 1501-1516 (1997)

Subsurface damage of fused silica lapped by fixed-abrasive diamond pellets

Zhichao Dong, Haobo Cheng, Xu Ye, and Hon-Yuen Tam
Appl. Opt. 53(26) 5841-5849 (2014)