2025-03-25 17:38:03

Why SWIR Cameras Can See Through Fog?

Fog significantly degrade visibility in the visible spectrum (400-700 nm), causing safety and operational challenges in autonomous driving, surveillance, and aviation. However, SWIR cameras excel in such conditions. Today’s let’s take a look at some reasons why SWIR camera has better performance.

Fog consists of tiny water droplets (1–10 µm in size) that heavily scatter visible light due to Mie scattering, where particles similar in size to the wavelength cause maximum diffusion. Since SWIR wavelengths are much longer than visible light, scattering is dramatically reduced, allowing clearer imaging through fog.

SWIR bands(e.g., 1.55µm, 2.2µm) fall within atmospheric transmission windows, where absorption by water vapor and CO₂ is minimal. This enables SWIR cameras to maintain high signal integrity even in humid or foggy environments.

Unlike long-wave infrared (LWIR, 8–14 µm) cameras that detect heat signatures, SWIR cameras rely on reflected light, similar to visible cameras. This allows them to capture high-resolution, high-contrast images while penetrating light fog, smoke, or dust.

The above are pictures of a SWIR camera penetrating fog VERSES visible light camera. The building behind the fog is clear under SWIR camera. Should you have any interest, please feel free to contact us!

Sales Manager: Lily Liu
Mobile: 086-13359283296
Email: info@gatherstarhk.com

Xi'an Gatherstar Optoelectronic System Co.,Ltd is specialized in infrared and laser photoelectric system products and module, components and elements. we are not only confident in supplying qualified optoelectronic products to all of our customers, but also concentrating on offering continuous innovations and reliable service.