Abstract
Multi-beam optical tweezers are one of the most suitable techniques for simultaneous, precise, and independent controlled micro-manipulation of numerous micro-beads under an optical microscope. Using a single laser source with 700 mW, we have developed a hybrid optical tweezers system consisting of two multi-beam techniques: the generalized phase contrast (GPC) method and the galvano mirror (GM) time-shared scanning method. The efficiency of trapping laser power was improved by optimizing of both fabrication process of a phase contrast filter (PCF) and coding procedure of phase values with a spatial light modulator (SLM). Consequently, our hybrid system could assemble micro-bead arrays composed of over a hundred beads without undesired stacking of beads along the beam axis. We were also able to manipulate several tens of micro-beads simultaneously and full-automatically, by singleness use of its GPC part.
