[OPTICAL REVIEW Vol. 5, No. 1 (1998) 55-58]

Spatial Arrangement of Small Particles by Imaging Laser Trapping System

Masahide ITOH, Masayuki TAKAHIRA and Toyohiko YATAGAI

Institute of Applied Physics, University of Tsukuba, Tsukuba, Ibaraki, 305 Japan

(Received July 29, 1997; Accepted November 19, 1997)

We describe spatial arrangement of polystyrene latex using a microscopic imaging system. A reduced photomask pattern is imaged on the particles in a water-filled cell so that polystyrene spheres align in a two-dimensional pattern. Calculating the forces exerted on the spheres by isolated line pattern, we investigated an optimum size for sphere diameter and the line width of the patterns. We are able to align spheres in real-time by this technique.

Key words : laser trapping, particle alignment, micro-manipulation, interferometer