Light Detection and Ranging – LiDAR

Lidar, which stands for Light Detection and Ranging, is a remote sensing method that uses light in the form of a pulsed laser to measure ranges (variable distances) to the Earth. These light pulses—combined with other data recorded by the airborne system — generate precise, three-dimensional information about the shape of the Earth and its surface characteristics.

A lidar instrument principally consists of a laser, a scanner, and a specialized GPS receiver. Airplanes and helicopters are the most commonly used platforms for acquiring lidar data over broad areas.

A huge city hidden by the luxuriant vegetation of the Amazon rainforest was recently discovered in Ecuador by a LiDAR survey.

How Does it Work?

- A LiDAR system calculates how long it takes for beams of light to hit an object or surface and reflect back to the laser scanner.
- The distance is then calculated using the velocity of light. These are known as ‘Time of Flight’ measurements.

Two types of lidar are topographic and bathymetric.

- Topographic lidar typically uses a near-infrared laser to map the land, while bathymetric lidar uses water-penetrating green light to also measure seafloor and riverbed elevations.

Lidar systems allow scientists and mapping professionals to examine both natural and man-made environments with accuracy, precision, and flexibility. It is used in a wide range of land management and planning efforts, including hazard assessment (including lava flows, landslides, tsunamis, and floods), forestry, agriculture, geologic mapping, and watershed and river surveys.

What is the difference between Radar and LiDAR?

LiDAR works in a similar way to Radar and Sonar yet uses light waves from a laser, instead of radio or sound waves.

Radar?

The word radar comes from the acronym radio detection and ranging. As the name implies, radars use radio waves to determine the distance and velocity of the targets they hit. A radar system usually consists of a transmitter to send out radio signals and a receiver to catch any reflected energy from targets.

Source:

Join Our Telegram

Thirty Meter Telescope (TMT)

Conjoined Silverline (Cigaritis conjuncta)

India–Azerbaijan

05 Apr, 26
SHARE

A year after tensions arising from Operation Sindoor, India and Azerbaijan have taken steps to restore and normalise bilateral relations. The 6th round of Foreign Office Consultations, held in Baku, marked the first such engagement since 2022, signaling renewed diplomatic momentum. Recent Diplomatic Engagement During the consultations, bo

India–Australia Economic Cooperation and Trade Agreem

04 Apr, 26
SHARE

The India–Australia Economic Cooperation and Trade Agreement has completed four years since its signing. Both countries now aim to build on this progress through strengthened collaboration and ambitious targets, including reaching AUD 100 billion in bilateral trade by 2030. What is the India–Australia Economic Cooperation and Tra

ADR Report on Political Funding

03 Apr, 26
SHARE

A recent report by the Association for Democratic Reforms (ADR) analyses donations of ?20,000 or more declared to the Election Commission of India (ECI) by national political parties for FY 2024–25, highlighting transparency and accountability in political financing. Key Findings Massive Funding Surge Total donations to nationa

Maritime Chokepoints

03 Apr, 26
SHARE

Maritime chokepoints are narrow channels along global shipping routes where maritime traffic is concentrated. These points are geopolitically and economically critical, as they handle a large proportion of global trade, especially energy shipments. Current Relevance Over two-thirds of seaborne energy trade passes through a handful o

US-Israel-Iran War

01 Apr, 26
SHARE

Following the launch of Operation Epic Fury (U.S.) and Operation Roaring Lion (Israel), the geopolitical landscape has shifted fundamentally with the confirmed death of Iran’s Supreme Leader, Ayatollah Ali Khamenei.Iran retaliated through Operation True Promise 4, launching missile attacks against Israel and nearby Gulf states. The escala