Understanding wavelength bands: applications and performances

The electromagnetic spectrum, divided into bands like Visible (VIS), Near Infrared (NIR), Shortwave Infrared (SWIR), Midwave Infrared (MWIR), and Longwave Infrared (LWIR), offers unique imaging and sensing capabilities. These bands excel in applications such as defense (night vision, thermal imaging, target tracking) and semiconductors (wafer inspection, defect detection). Each band’s distinct properties—such as visibility, thermal sensitivity, and penetration through fog or smoke—enable enhanced precision, reliability, and efficiency in critical industries, driving innovation and technological progress.

Visible (VIS) Band (0.38-0.75 µm)

• Application: standard imaging
  The VIS band corresponds to the wavelengths of light visible to the human eye. It is widely used for traditional imaging systems, such as Nedinsco’s PBUS, DUALCAM, EMES, Back-Up Sight, and boresights.
• Sensitivity to light: very high
  The VIS band offers excellent sensitivity in well-lit environments, making it ideal for daytime imaging.
• Night/low-light performance: poor
  The performance of VIS-based imaging systems drops drastically in low-light conditions due to the reliance on visible light, however with present LLC CMOS sensors the performance is increasing by every new generation.
• Thermal sensitivity: none
  The VIS band cannot detect thermal radiation and is unsuitable for thermal imaging applications.

Near Infrared (NIR) Band (0.75-1 µm)

• Application: night vision
  NIR is commonly used in vision systems which also operate in low light conditions like the EMES and DUALCAM camera. These cameras operate both in the visible spectrum and just beyond the visible spectrum, capturing light not visible to the human eye and thus enhancing the capability of the camera in low(er) light conditions during dusk and dawn.
  A 2^nd way of operating in low light conditions is the use of image intensifiers (or I²T), who as the name suggests greatly intensify the amount of light present and thus form a usable image to the user.
• Sensitivity to light: high
  NIR cameras perform well in dimly lit environments, capturing details invisible in the VIS band. In daylight conditions the I²T camera’s must be protected against too much light.
• Night/low-light performance: excellent
  Night vision technologies such as Nedinsco’s DUALCAM and EMES camera use this band for superior performance in low-light conditions.
• Thermal Sensitivity: low
  While the NIR band can detect slight temperature variations, its thermal sensitivity is limited compared to longer wavelengths.

Shortwave Infrared (SWIR) Band (1-3 µm)

• Application: low-light imaging and penetration through smoke & fog
  SWIR can penetrate environmental obstructions like smoke or fog, making it valuable for surveillance , firefighting forces and industrial inspection.
• Sensitivity to light: medium
  SWIR strikes a balance between visible light and thermal infrared, making it suitable for various imaging applications, such as driving in foggy environments and detecting IED’s under certain conditions.
• Night/low-light performance: good
  SWIR performs well in low-light conditions and adds the ability to penetrate challenging atmospheric conditions.
• Thermal sensitivity: moderate
  SWIR offers some thermal sensitivity, allowing for limited temperature detection in certain scenarios.

Midwave Infrared (MWIR) Band (3-5 µm)

• Application: precision temperature measurement
  MWIR excels at detecting and measuring temperature differences with high precision, making it indispensable for military applications, long range targeting, long range surveillance, such as used the CLAIRE camera.
• Sensitivity to light: none
  While MWIR is not sensitive to ambient light, MWIR operates effectively in a range of environmental conditions, making it very suitable for e.g. long-range detection in harsh weather conditions at sea or target tracking in challenging situations on the ground.
• Night/low-light performance: Good
  MWIR imaging requires specific thermal contrasts, and is not dependent on visible light.Making it suitable for day and night operations.
• Thermal sensitivity: very high
  With the ability to detect subtle thermal details, MWIR systems are less affected by humidity than LWIR systems for most target ranges making it suitable for applications like coastal surveillance, vessel traffic surveillance or harbor protection. For very long-range target detection (at >10km), MWIR has greater atmospheric transmission than LWIR in most climates

Longwave Infrared (LWIR) Band (8-14 µm)

• Application: thermal imaging
  LWIR is optimized for thermal detection, capturing heat signatures independent of visible light.
• Sensitivity to light: none
  LWIR does not rely on visible light, making it independent of ambient lighting conditions.
• Night/low-light performance: independent of light
  LWIR camera systems like the OTUS Driver Vision Enhancement family perform equally well in both day and night, as they detect infrared radiation emitted by objects.
• Thermal sensitivity: high
  With strong thermal sensitivity, LWIR is widely used in applications such as day and night Driver Assistance Systems, short range object identification in day and night situational awareness. LWIR band is better than MWIR for imaging through smoke or aerosols and has better performance than MWIR in foggy conditions, so LWIR is usually the chosen technology for firefighting applications and for military applications like driver cameras.

Supporting a wide range of applications

The diversity of electromagnetic spectrum bands enables a wide range of applications. In security and surveillance, Near Infrared (NIR) and Shortwave Infrared (SWIR) bands play a critical role in low-light vision and monitoring in obscured environments. For industrial inspection, Midwave Infrared (MWIR) and Longwave Infrared (LWIR) bands are essential for detecting heat leaks, monitoring machinery, and ensuring process quality. In military and defense, land-based applications utilize multi-band imaging for improved operational effectiveness, while naval operations benefit from enhanced imaging capabilities across multiple bands.

Enhancing modern warefare

In both land and naval domains, the integration of VIS, NIR, SWIR, MWIR, and LWIR technologies significantly enhances situational awareness, precision targeting, and operational effectiveness. From detecting camouflaged enemies on land to identifying threats in open seas, these technologies provide a strategic advantage, ensuring military forces maintain dominance in complex and dynamic environments.

This reliance on multi-band imaging underscores its critical importance in the modernization of defense systems globally.
By understanding the unique properties and capabilities of these bands, our engineers will help you choose the most suitable wavelength for specific applications.