A Novel Micro Optical System for Monolithic Integration of Optical Disk Pickup Heads

摘要

As the progress of IT, the need for high speed and high-density data storage has become increasingly important. Denser and faster data storage methods have also been under developing for next generation need. As a result, the performance of optical storage units, such as an optical pickup head, need to be further improved to accommodate this new desire. However, commercial optical disk pickup head is mostly constructed with bulk micro-optics and many discrete components. The assembly needs intensive labors and poses large-size heads, greatly limiting operation speed and alignment accuracy. This study proposes a novel method to integrate precisely fabricated inclined-mirrors and on-chip Fresnel lens for optical pickup-head application. A new technology of glycerol-compensated incline-exposure has been adopted for the fabrication of 45° mirror pairs. This new integration approach provides an easy and low cost fabrication mean without the need of assembly. Furthermore, this study also proposes a novel method to fabricate the micro SU-8 lens. The novel SU-8 micro lens can be integrated with the micro optical pick-up head as a micro objective lens.