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Once limited to military and governmental applications, first-generation night vision equipment is now available for civilian use at a price affordable to many. Night vision devices find practical applications in boating safety, wildlife observation and night photography as well as by forming an unobtrusive part of home security... more »
Humans as a species have very poor night vision, especially compared to other mammals. The eyes can only process a small portion of the electromagnetic spectrum, which is the measurement of all electromagnetic radiation. To put it simply, human eyes can only see a very small percentage (called visible light) of what is actually going... more »
Thermal imaging and infrared cameras were originally developed for military use during the Korean War. Although the use of thermal imaging has now expanded into other fields, it is still primarily used by the United States Armed Forces. The military has developed advanced software interfaces and optic sensors that continue to advance... more »
Infrared cameras were first created during the Korean War. The military has long used these cameras to enable night vision for many reasons. Gradually infrared cameras have begun to be used for other purposes. The police are one group that has found many different uses for infrared cameras. more »
A thermagraphic or thermal camera, also known as a FLIR (forward looking infrared), is a device that creates an image using infrared radiation, which is heat. The measurement of the infrared light illustrates and makes visible the heat radiation from the object. There are different types of thermal cameras which are utilized in... more »
A home is one of the biggest investments any person can make so it's in your best interest to...
Night-vision mode is a popular feature on many camcorders. With night vision, the camcorder can record in low light to complete darkness,... more »
A night vision webcam is a camera that is able to detect infrared light. All webcams are equipped with this ability, but they are also equipped... more »
If you have decided that a night-vision security camera will suit your needs, follow these instructions for installation. more »
ATN Night Patriot Night Vision monocular is a versatile device. You can convert this device into a Goggle System as well. Here’s how to turn the... more »
You can use the ATN Night Storm Night Vision Monocular for several activities such as hunting, camping, boating or even surveillance. There are... more »
Night vision is the ability to see in a dark environment. 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 lucidum.
Night vision
Spectral range
Night-useful spectral range techniques make the viewer sensitive to types of light that would be invisible to a human observer. Human vision is confined to a small portion of the electromagnetic spectrum called visible light. Enhanced spectral range allows the viewer to take advantage of non-visible sources of electromagnetic radiation (such as near-infrared or ultraviolet radiation). Some animals can see well into the infrared and/or ultraviolet compared to humans.
Intensity range
Sufficient intensity range is simply the ability to see with very small quantities of light. Although the human visual system can, in theory, detect single photons under ideal conditions, the neurological noise filters limit sensitivity to a few tens of photons, even in ideal conditions.
Many animals have better night vision than humans do, the result of one or more differences in the morphology and anatomy of their eyes. These include having a larger eyeball, a larger lens, a larger optical aperture (the pupils may expand to the physical limit of the eyelids), more rods than cones (or rods exclusively) in the retina, a tapetum lucidum, and improved neurological filtering.
Enhanced intensity range is achieved via technological means through the use of an image intensifier, gain multiplication CCD, or other very low-noise and high-sensitivity array of photodetectors.
Biological night vision
In biological night vision, molecules of rhodopsin in the rods of the eye undergo a change in shape as light is absorbed by them. Rhodopsin is the chemical that allows night-vis read more at » http://en.wikipedia.org/wiki/Night+vision
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