Optical tweezer, as known as single beam optical tarp, grabs small particles of micrometer-size even nanometer-size by the force from photo momentum transfer.

• 而光钳是单一光束所造成的光学嵌住，是利用光子动量转移所造成的作用力来抓取微小物体，可用来操控微米级甚至奈米级的微小物体。