While many of us think that night vision lenses might work for the above-mentioned tasks, there are some major differences between the two that prove why thermal imaging lenses are a better fit for such security applications.
While night vision goggles require at least nearby visible light for its functioning, thermal imaging lenses don’t need any light and mostly use infrared sensors to identify differences in temperatures of objects in line of vision.
In addition, the former catches a scene and magnifies its light to translate it to green-tinted images, whereas the latter ones convert heat signals into viewable images. Moreover, night vision goggles can get impaired by rain, fog, dust, and smoke unlike thermal imaging lenses which remain unaffected under these conditions.