Grier and his students manipulated two tweezers to measure the interaction between microscopic beads.Each tweezer captured one bead and, when the trap was turned off, released it.

• 葛利尔和学生就用两把光钳测量微粒间的交互作用，每把钳子紧抓住一颗微粒，然后关掉光阱释放该粒子。