What wavelengths does LiDAR use?

Wavelengths Used in LiDAR Technology

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 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. LiDAR technology employs various wavelengths of light, each selected based on the specific application and the objective of the LiDAR system. The most commonly used wavelengths in LiDAR systems are:

• Near-Infrared (NIR): Around 1550 nm – This wavelength is predominantly used in terrestrial and airborne LiDAR systems for mapping and surveying because it offers a good balance between measuring distance accurately and being safe for human eyes.
• Short-Wave Infrared (SWIR): About 1064 nm – This wavelength is often used in applications requiring penetration through water or measuring atmospheric parameters since it offers better penetration through particles and certain materials.
• Green Light: Approximately 532 nm – Ideal for bathymetric (underwater) LiDAR systems, as this wavelength penetrates water with greater efficiency, making it suitable for mapping seabed and riverbed elevations.
• Ultraviolet (UV): Around 355 nm – Used for specialized applications that require detecting fine particles and pollutants in the atmosphere. This wavelength can also be employed in forensic investigations and geological surveys.

Each of these wavelengths has its distinct advantages and is chosen based on the need for penetration, resolution, and environmental considerations. The choice of wavelength plays a crucial role in the safety, efficiency, and effectiveness of a LiDAR system.