Passive optical separation and enrichment of cells by size difference.

A size-selective cell sorting microfluidic device that utilizes optical force is developed. The device consists of a three-dimensional polydimethylsiloxane microstructure comprised of two crossed microchannels in a three-dimensional configuration. A line shaped focused laser beam is used for automatic size-selective cell sorting in a continuous flow environment.

Fabrication of concave silicon micro-mirrors.

We have fabricated spherical and cylindrical concave micro-mirrors in silicon with dimensions from 20 microm to 100 microm. The fabrication process involves standard photolithography followed by large area ion beam irradiation and electrochemical anodisation in a HF electrolyte. After thermal oxidation the silicon surface roughness is less than 2 nm.