Recently our group demonstrated the ability to trap bacteria using optical tweezers, but low laser power limited trapping ability. I will report on improvements made to both laser power and beam quality, which lead to improved trapping ability. Initial results were seen to increase laser intensity at the sample, but the beam quality was severely degraded. The solution to this problem was to better shape the laser beam using an anamorphic prism pair. This process was repeated for a higher power laser diode. We were able to maintain a high quality beam while more than doubling laser power at the sample. This was evidenced by a larger fraction of light passing through the spatial filter and by higher translational speeds than previously observed.
Knecht, Matthew, "Optimization of Optical Tweezers" (2007). Senior Research Projects. 18.