What is NightVision?
It is the ability to see things in low-light conditions. This can be achieved through biological and technological means. Animals have superior night vision than humans because we lack the tissue layer called Tapetum Lucidum.
How night vision happens biologically?
Photoreceptor cells in the eye are a combination of color vision cells, night vision cells and retinal. These three are responsible for the normal vision when they absorb light.
But the night vision adaption happens in the first five minutes in the dark. This results in maximum sensitivity towards a light. The Rhodopsin in night vision cells (Rod cells) are sensitive towards the dark and they trigger the vision in the dark.
What’s the reason for the severe vision loss?
Motion detection is key to the survival of any animal, so the vertebrae eye contain four motion-sensitive cells (up, down, right and left). This motion perception loss is the common grievance for a person’s severe vision loss.
Mechanics of Night Vision wildlife:
The software and hardware of the light-sensing retinal circuits in the vertebrate eye change according to the intensity of low-light. The night vision you see on Full Moon and New Moon days are entirely different from each other.
When an object moves in a particular direction a large population of that side neurons triggers a strong field. If the motion is between two sides both populations trigger fields and the brain deciphers the kind of signal and the motion direction. Reprogramming in the retinal cells happens constantly as they are motion sensitive.
For conducting the complex tasks, the brain employs the large populations of neurons.
In humans, only 4% of the directional neurons send signals from the retina to the brain. But in Rodents, the field added is like 20-30%, because the motion detection is a natural phenomenon in them for their survival.
Experiments on the night vision:
A number of experiments were conducted on the subject called Night Vision. Testing the sample of the mouse retina placed on an electrode array, resulting in data of signal triggering of neurons during day and night.