Trapping of a few microscopic dielectric beads with at single optical tweezer is a commonly encountered phenomenon in optical trapping experiments. The confinement of tens of such beads using a single optical trap has not been reported. Here we present experimental results of optical confinement of up to 37 2.5-µm-diameter silica beads using a NIR gaussian laser and a 100x microscope objective with numerical aperture of 1.25, on an inverted configuration. The position of the beam wait along the vertical axis is a crucial parameter for the success of this multiple trapping.
© 2015 Optical Society of AmericaPDF Article