光镊或光钳（英文：optical tweezers）是一种通过高度聚焦激光束产生力（量级通常为皮牛顿级）移动微小透明物体的设备。其中把持物体的区域也称为光阱(optical trap)，相应的技术称作光学捕捉(optical trapping)。这种技术可以用于移动细胞或病毒颗粒，把细胞捏成各种形状，或者冷却原子。由于光镊的力可以精准地直接作用于细胞甚至更小的目标，光镊在生物学方面的应用越来越广泛。

显微镜升级改造为光镊的方法：NanoTweezer显微镜纳米激光镊转换装置5分钟内将显微镜升级为纳米激光镊。

Optical tweezers (originally called "single-beam gradient force trap") are scientific instruments that use a highly focused laser beam to provide an attractive or repulsive force (typically on the order of piconewtons), depending on the refractive index mismatch to physically hold and move microscopic dielectric objects similar to tweezers. Optical tweezers have been particularly successful in studying a variety of biological systems in recent years.