OUT-OF-PLANE REFRACTIVE MICROLENS FABRICATED BY SURFACE MICROMACHINING

A novel refractive microlens standing perpendicular to the substrate h as been fabricated for the first time with surface-micromachining tech niques. The microlens has a focal length of 670 mu m and a diameter of 300 mu m. The optical axis of the microlens is precisely defined by p hotolithography and can be pre-aligned to other surface-micromachined micro-optical elements integrated on the same substrate. The focusing and collimating abilities of the lens are successfully demonstrated. T he refractive microlens offers higher efficiency compared with diffrac tive lenses, and is very useful for high-performance free-space micro- optical bench applications.