The implementation of concave micro optical devices using a polymer dispensing technique

Abstract

This study demonstrates a novel approach to implementing a double-concave (DCV) microlens using a simple polymer dispensing and sucking process. The DCV microlens is implemented at room temperature using a commercially-available pneumatic-controlled polymer dispensing system. The DCV lens profile can be tuned by varying the volume of the dispensed polymer. It is also easy to integrate the present polymer DCV microlens with other suspended micromachined devices such as silicon nitride film and silicon-on-glass (SOG) micromachined structures. This study further employs the process for DCV to implement a concave mirror. The measurement results show a typical DCV lens (made of NOA63 polymer) with negative focal lengths of −1.42 mm (red laser) and −1.17 mm (blue laser), and a concave mirror with a focal length of 3.28 mm. Moreover, this study also demonstrates the integration of a DCV microlens with other optical components, such as plano-convex and double-convex lenses.