Night vision is the ability to see in low light conditions. Whether by biological or technological means, night vision is made possible by a combination of two approaches: sufficient spectral range, and sufficient intensity range. Humans have poor night vision compared to many animals, in part because the human eye lacks a
tapetum lucidumThe tapetum lucidum is a layer of tissue in the eye of many vertebrate animals....
.
Night-useful spectral range techniques can sense radiation that is invisible to a human observer.
