The term night vision refers to the ability to see when there is not enough light. Usually, night vision is made possible by a combination of sufficient intensity range and sufficient spectral range. Sufficient intensity range refers to the ability of seeing objects in low light condition. It has been observed that humans have poor night vision as compared to most animals.
This is largely because of the differences in the anatomy and morphology of their eyes. On the other hand, the spectral range techniques can sense the radiation that is invisible to a human observer. Their vision is restricted to a certain range of electromagnetic spectrum that is called visible light.
In order to ensure improved vision in low light conditions, Intellisystem Technologies offer a wide range of IR illuminators.
Dear Cristian,
All mammals including humans have an amazingly wide range of light sensitivity. We can see by star light alone on moonless nights and adapt successfully to noon tropical sunlight which is several orders of magnitude stronger. To achieve this we have two distinct visual sensor systems called Rods and Cones. The ‘photopic’ Cone response is essentially trichromatic and delivers colour vision in normal daylight and it is also closely focused on visual detail. As daylight fades away the ‘scotopic’ Rod response takes over, which is effectively monochromatic. You are unlikely to experience scotopic night vision in an urban environment but when you do, it feels distinctly different. With night vision the ability to focus is much reduced, perception of detail is replaced by a feeling of openness; and we sense our surroundings more acutely. So, if you take your dog for a moonlight walk in the country and look at the dog closely, it will seem to disappear (I’ve tried this and it works).
Genetically as with all mammals, we have evolved to have focused ‘predatory vision’ in daylight and ‘prey-animal surround-vision’ at night.
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