Surface Inspection of Micro Glass Lens Mold Based on Total Angle Resolved Scattering Characterization
Terutake Hayashi, Yasuhiro Takaya, Naohiro Motoishi,
and Yuki Nakatsuka
Department of Mechanical Engineering, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
The condition of the lens mold surface becomes worse due to several defects that are caused in the lens production process as the number of lens shots increases. An on-machine quantitative evaluation method is required for the lens mold surface. In this study, we have developed an automated light scattering measurement system that enables 3-D detection of the scattered light in various directions caused by flaws and roughness in order to characterize the surface texture and manufacture a high quality lens. The surface characteristic of the lens mold is classified using the scattered patterns. This paper describes the quantitative evaluation results of the surface nano texture for characterizing the spherical lens mold with varying shot numbers.
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