[OPTICAL REVIEW Vol. 10, No. 4 (2003) 290-294]
© 2003 The Optical Society of Japan

The Effect of Wettability of Nickel Mold Insert on the Surface Quality of Molded Microlenses

Namsuk LEE1, Su-dong MOON2, Shinill KANG1,2,* and Suho AHN3

1School of Mechanical Engineering, Yonsei University, 134 Shinchon-dong, Seodaemoon-ku, Seoul, Korea
2Center for Information Storage Device, Yonsei University, 134 Shinchon-dong, Seodaemoon-ku, Seoul, Korea
3Optics Division, Optomecha Co. Ltd., Seoul, 120-749, Korea

(Received February 3, 2003; Accepted June 27, 2003)

In micromolding of microlens array, it is important to prepare a mold insert of superb quality, which contains the micro-cavity of lens shape, because the geometrical quality of the mold insert defines the final quality of the molded micro-optics. In the present study, the electroforming process was used to make the metallic micro-mold insert for micro-molding of microlens array. The wettability property of the fabricated mold isnert was examined by measuring the contact angle of the polymer in the pliable state on the mold insert. Microlenses were compression-molded with the fabricated mold insert. The effects of the molding temperature and wettability property on the replication quality of the molded lenses were analyzed experimentally.

Key words: micro-mold insert, electroforming, microlens, replication quality, wettability

*Author to whom correspondence should be addressed. E-mail: snlkang@yonsei.ac.kr