In everyday life people often mention the word laser, and then for the function and the specific definition of the laser derived is rarely known, this paper will give you an analytical laser radar and laser ranging.

激光测距是通过由传感器（激光雷达)所发出的激光来测定传感器与目标物之间距离的主动遥感技术。该项技术根据探测目标的不同，可分为对空探测和对地探测两类。对空激光测距旨在通过向空中发射激光束并接受由空气中悬浮颗粒所反射的回波来完成对大气物理及化学性质的测定。对地激光测距的主要目标是获取地质、地形、地貌以及土地利用状况等地表信息。按照传感器搭载平台分类，激光测距可分为星载（卫星搭载）、机载（飞机搭载）、车载（汽车搭载）以及定位（定点测量）四大类。

Laser ranging is an active remote sensing technique for measuring the distance between the sensor and the target by the laser emitted by the sensor (laser radar). The technology can be divided into two kinds of space exploration and ground detection according to the different targets. The measurement of the physical and chemical properties of the atmosphere by means of a laser beam emitted from the air to the air and by receiving the echoes reflected by the suspended particles in the air. The main target of the ground laser distance measurement is to obtain the surface information such as geology, terrain, landform and land use. According to the sensor mounted platform classification, laser ranging can be divided into satellite (satellite), airborne (aircraft), vehicle (car equipped) and positioning (fixed point measurement) four categories.

激光测距技术始于二十世纪六十年代，到七八十年代，激光技术已经是电子测距设备中的重要组成部分。LIDAR （Light Detection And Ranging) 通常指机载对地激光测距技术，中文术语常用激光雷达来代指LIDAR。在美国，自上世纪七十年代起，包括美国国航太空总署（NASA）、美国国家海洋大气总署（NOAA）以及美国国防测绘部（DMA）在内的多家机构开始发展LIDAR类的传感器用于海洋及地形的测量。在欧洲，激光测距的相关研究差不多与美国同时起步，不同于美国的是，他们致力于发展卫星平台激光测距雷达系统，更专注机载平台及与之相配的激光雷达系统的开发研究，并取得了相当程度的成功。

Laser ranging technology began in 1960s, to seventy or eighty years, laser technology has been an important part of electronic distance measurement equipment. LIDAR (Detection And Ranging Light) is generally referred to as the airborne laser ranging technology, the Chinese term used to refer to the laser radar LIDAR. In the United States, since the seventies of the last century, including the United States Air Space Agency (NASA), the National Oceanic and Atmospheric Administration (NOAA) and the Ministry of the Defense Mapping (DMA), many institutions began developing lidar sensor for measurement of ocean and terrain. In Europe, research on laser ranging almost with the United States started at the same time, is different from that of the United States, their commitment in the development of satellite laser ranging radar system, to focus more on the research and development of the airborne platform and matched with the laser radar system, and have achieved considerable success.

到上世纪九十年代，随着机载GPS技术以及便携式计算机系统的发展，LIDAR系统的稳定性及精确度得到了大幅提高，并逐步开始在欧洲投入商业化使用，与之相关的应用性研究也随即率先在欧洲展开。

To the nineties of the last century, along with the development of Airborne GPS and portable computer system, the stability and accuracy of the lidar system has been greatly improved, and gradually began in Europe put into commercial use, and the related application research immediately took the lead in Europe.

相对于其他遥感技术，LIDAR的相关研究是一个非常新的领域，不论是在提高LIDAR数据精度及质量方面还是在丰富LIDAR数据应用技术方面的研究都相当活跃。与遥感影像技术不同的是，LIDAR系统可以迅速地获取地表及地表上相应地物（树木、建筑、地表等）的三维地理坐标信息，它的三维特性符合当今数字地球的主流研究需求。

Compared with other remote sensing technology, lidar research is a very new field, whether it is in improving the lidar data accuracy and quality or in rich lidar data application technology research are very active. With the remote sensing technology, lidar system can quickly obtain the earth 's surface and the corresponding objects (trees, buildings, and ground) three dimensional geographic coordinate information, three-dimensional characteristics it conforms to the demand of the main trends of today's digital earth.

随着LIDAR传感器的不断进步，地表采点密度的逐步提高，单束激光可收回波数目的增多，LIDAR数据将提供更为丰富的地表和地物信息。对LIDAR所采集到的地表三维点集进行过滤、插值、分类、分割等处理，可获取各类高精度的三维数字地面模型，还可对地表地物进行分类识别并实现地表地物如树木、建筑等的三维数字重构，乃至绘制三维森林、三维城市模型，构建虚拟现实。在虚拟现实的基础上进行更为精细的地物分析，可对林地及其单株立木的各项参数进行估计，从而实现精细林业、农业的经营管理；可对城市规划、城市环境及城市气候进行模拟分析，实现对声、光、环境污染状况的评估与控制。

With the continuous progress of LIDAR sensor, the gradual improvement of surface mining density, single beam laser can recover the number of wave number, LIDAR data will provide more abundant information on the surface and surface features. Which is collected by the lidar surface 3D point set filter, interpolation, classification and segmentation processing, all kinds of high precision of 3D digital terrain model acquisition, but also on the surface of classification and Realization of ground objects such as trees and building of 3D digital reconstruction, but to draw the forest 3D, 3D city models to construct virtual reality. In virtual reality based on more detailed terrain analysis, parameters of forest and tree estimation, so as to realize the precision forestry, agriculture management; to urban planning, urban environment and urban climate for simulation analysis, implementation of sound, light and environment pollution situation assessment and control.