First of all, in terms of resolution, the resolution of infrared images is relatively low, while the resolution of low-light images is much higher than it.

 

Secondly, in terms of contrast, the contrast of infrared images is higher than that of low-light images. The low-light system works by night sky lighting, the contrast between the scenes is small, and the image layers are not clear enough.

 

Thirdly, under the influence of the external environment, the generation of low-light images is greatly affected by external factors, such as weather, starlight, smoke and other factors. In contrast, infrared images have lower requirements, because all objects higher than OK will radiate infrared rays outward, so infrared can also work in some situations where the external environment is very unfavorable.

 

Finally, in terms of detection distance, the external environment has a certain influence on them. For example, for infrared, the detection distance is related to the target background radiation, atmospheric transmittance characteristics and system response characteristics. For low light, the detection distance is related to the aperture of the detector's objective lens, the contrast between the target and the background, and the integral sensitivity of the detection device, but in general, infrared has a farther distance than low light.

 

The infrared and low-light images are compared from the four aspects of resolution, contrast, use conditions and detection distance. They each have some advantages and disadvantages, and they can be combined according to a certain algorithm. respective advantages. Due to the influence of their respective optoelectronic devices and photoelectric conversion characteristics, the radiation of different objects may generate the same photocurrent, which affects people's judgment. For example, in infrared imaging, there may be two different objects that generate the same radiation. A similar situation occurs in low-light imaging. For example, in the green tank in front of the cement building, the photocurrent generated by the light power reflected on the photosensitive surface of the low-light optoelectronic device is equivalent to this, so it is difficult to distinguish. After the fusion, since the infrared and low-light images reflect the imaging of different properties of the object, that is, the infrared is the radiation image, and the low-light image is the reflection image, so the detection capability of the system can be improved. Taking advantage of the good ability to describe details in low light, the all-weather passive observation ability of infrared and the long detection distance of infrared, the performance of the night vision system can be greatly improved.

 

Due to the different working mechanisms of infrared and visible light sensors, the imaging performance is very different. The infrared imaging sensor obtains the infrared radiation of the mouth mark, and identifies the target by detecting the difference in thermal radiation between the target and the background. Although the infrared sensor has good detection performance for the thermal mouth mark, it is not sensitive to the brightness change of the scene, so the infrared image clarity And the low spatial resolution is not suitable for observing the cognition of scene details.