​Understanding Infrared Shortwave Lens

SWIR short-wave infrared lens Application background:

Near infrared (SWIR) or short-wave infrared light is generally defined as light in the wavelength range of 0.9 to 1.7μm, but can also be classified as the wavelength range of 0.7 to 2.5μm. Human eyes can not directly perceive the existence of infrared, so humans need to use photoelectric instruments to obtain information generated under the action of infrared. Short-wave infrared imaging allows users to "see beyond the visible range" of imaging, such as detecting dents or bruises to detect fruit, in visual imaging, the fruit is not defective; In short-wave infrared imaging, the bruising inside the fruit can be clearly seen.

For example, to detect the amount of internal filling in opaque packaging, the SWIR short-wave infrared lens can be used to "see" the filling in the bottle. Short-wave infrared imaging is widely used to detect the drying uniformity of paint or bulk materials, electronic panel inspection, solar cell inspection, remote monitoring of temperature and uniformity during metal smelting, and so on. The "illumination effect" of shortwave infrared is the same as that of visible light, in that shortwave infrared light is reflected or absorbed by the object, providing a strong contrast to support higher resolution imaging. Ambient starlight and background radiation (atmospheric glow) are natural short-wave infrared emitters that provide superior illumination for outdoor or nighttime imaging, including through fog, smoke, and water vapor.

SWIR short-wave infrared lens imaging features:

1) High recognition: SWIR imaging is mainly based on the principle of target reflected light imaging. Its imaging features are similar to those of visible gray scale images, with high imaging contrast and clear expression of target details. In terms of target recognition, SWIR imaging is an important supplement to thermal imaging technology.

2) All-weather adaptation: SWIR short-wave infrared lens imaging is less affected by atmospheric scattering, strong ability to penetrate smoke, fog or haze, long effective detection distance, and adaptability to climate conditions and battlefield environment is significantly better than visible light imaging;

3) Low-light night vision: under the night-vision condition of atmospheric glow, photon irradiance is mainly distributed in the SWIR band range of 1.0-1.8um, which makes SWIR night vision imaging have significant innate advantages compared with visible light night vision imaging. Image details can be extracted from deep shadows and can be imaged through window glass, especially for use in the dark or at night.

4) Covert active imaging: in the 0.9-1.7um band, the military laser light source technology is mature (1.06um, 1.55um), which makes SWIR imaging in the covert active imaging application has a significant comparative advantage;

5) Optical configuration is simple: SWIR light can penetrate the glass, SWIR camera does not need a special shell, as long as a protective window glass can be assembled, when applied to a specific platform or occasion, with great flexibility.