Demonstration of vertical (a-b) and horizontal (b-d) movement of spatially trapped 15 micm polystyrene microsphere (white arrow). The beam focus was fixed and so the trapped sphere stays at the same position. The second sphere lies on the microscope slide and follows the motion of the microscope stage.

Demonstration of vertical (a-c) and horizontal (c-d) movement of spatially trapped 5 micm polystyrene bead (white arrow). The trapped bead stayes fixed while the second one lying on the surface changes its sharpness as the microscope stage moves. 

Demonstration of vertical (a-b) and horizontal (b-d) movement of spatially trapped 1 micm polystyrene bead (white arrow). Again the trapped bead stays at the same position while the rest of beads lies on the movable microscope stage.

Optically trapped bacterial cell (a). The following  pictures (b-e) show a protozoa Colpidium trying to leave the optical trap where it is kept by optical tweezers. Switching off the laser beam releases the Colpidium from the trap (f).

Demonstration of vertical (a-b) and horizontal (c-f) movement of spatially trapped 295 nm polystyrene bead. The optical trap together with the trapped bead was translated by movable telescope lens. 

A protozoa Paramecia were "fed" by 5 micm polystyrene microspheres. One of these spheres  was trapped by optical tweezers and served as an inner handle that rotated the whole vacuole (see images a-d). 

"Feeding" amoeba with bacterial cell trapped in optical tweezers and shifted to the proximity of amoeba membrane. Within a short time the amoeba started to grap (phagocytize) the bacteria.(realtime movie) 

Optical manipulation with the internal organelle (size of 1 micm) of mice carcinoma cell.