Effect of Punch Geometry on Stress and Strain Distribution During Contact Lens Demolding
Ching-Mu Cheng, Yun-Shao Cho, Tieh-Fei Cheng, Jui-Yu Wang, Jung-Jie Huang · 2025
Read Effect of Punch Geometry on Stress and Strain Distribution During Contact Lens Demolding by Ching-Mu Cheng, Yun-Shao Cho, Tieh-Fei Cheng, Jui-Yu Wang, Jung-Jie Huang (2025) in the Tower of Babel, a free online library of public-domain works preserved in clean, searchable text. No sign-up. The full text is served as a plain-text file at a predictable URL, where text is present: https://antarctic-labs.com/tower-of-babel/pmc-12844106.txt.
Description
Ching-Mu Cheng and four colleagues present a 2025 engineering study on a humble step in contact lens making: popping the fresh lens out of its mold. The release is done with a punch, and a bad punch shape stresses the mold and ruins lenses. Using computer simulation, the team tested punch geometries for how they spread stress in the polypropylene mold.
A flat punch with a shallow arc groove in its center spread stress best and deformed the mold least. In a hundred-cycle trial, lenses released more smoothly and centered better, and the good-lens yield reached eighty-two percent, thirteen points above a plain flat punch. The authors say the small shape change cuts costs and raises throughput on the production line.
Catalog record
| CREATOR | Ching-Mu Cheng, Yun-Shao Cho, Tieh-Fei Cheng, Jui-Yu Wang, Jung-Jie Huang |
|---|---|
| YEAR | 2025 |
| COLLECTION | PAPERS |
| FORMAT | TXT |
| FILE SIZE | 21 KB |
| VERSION | 1.0 |
| LICENSE | CC BY 4.0 |
| RIGHTS | CC BY |
| SOURCE | Europe PMC |