光学雷达（英语：lidar, LIDAR, LiDAR,Light Detection And Ranging），或简称光达，是一种光学遥感技术，它通过向目标照射一束光，通常是一束脉冲激光来测量目标的距离等参数。激光雷达在测绘学、考古学、地理学、地貌、地震、林业、遥感以及大气物理等领域都有应用 此外，这项技术还用于机载激光地图测绘、激光测高、激光雷达等高线绘制等等具体应用中。

激光雷达对物体距离的测量与通常所说的雷达类似，都是通过测量发送和接受到的脉冲信号的时间间隔来计算物体的距离。因此，由于原理上的相似性，尽管雷达的准确定义是使用微波或无线电波等波长较长的电磁波进行检测测距的设备，激光雷达这一术语仍然被广泛使用。

Lidar (also written LIDAR, LiDAR or LADAR) is a surveying technology that measures distance by illuminating a target with a laser light. Lidar exists as an acronym of Light Detection And Ranging, and was originally created as a portmanteau of "light" and "radar". Lidar is popularly used as a technology to make high-resolution maps, with applications in geodesy, geomatics, archaeology, geography, geology, geomorphology, seismology, forestry, atmospheric physics, airborne laser swath mapping (ALSM) and laser altimetry. What is known as Lidar is sometimes simply referred to as laser scanning or 3D scanning, with terrestrial, airborne and mobile applications.