How far can IR video cameras monitor? With advanced technology, it is not difficult to have an infrared night vision system above 100 meters. Advanced technology means it must be combined with IR light technology, infrared sensor camera technology and infrared lens technology at the same time. These three are indispensable.
First of all, there is a waste of light if the infrared light with a large viewing angle is combined with a lens with a small viewing angle. In addition, a large angle of the infrared light does not mean a good picture effect.
Luminous flux: The relative aperture determines the light transmission capacity of the lens. The luminous flux of a lens with a relative aperture of f1.0 is four times that of a lens with a relative aperture of f2.0. When the same camera and infrared light are matched with the above two lenses respectively, the infrared action distance can be doubled. In terms of infrared monitoring, the large-aperture lenses are four to ten times better than conventional ordinary lenses, and it should be a necessary supporting product for IR night vision camera monitoring. However, due to the high cost and technical difficulty, the majority of infrared product manufacturers do not have the ability to supply them.
Due to the different wavelengths of visible light and infrared light, the imaging focus is not on the same plane, which results in clear images under visible light conditions during the day while blurry images under infrared light conditions at night. Or the image is clear under infrared light conditions at night while the image is blurred under visible light conditions during the day. It can be solved in three ways. Firstly, an automatic focusing integrated camera can be used. Secondly, a dedicated lens that does not shift the focus can be used. Thirdly, professional adjustment tools can achieve no shifting under the existing lens conditions.
All black and white cameras are sensitive to infrared light. Infrared light is a type of stray light for color cameras under visible light conditions, which will reduce the clarity and color reproduction of color cameras. The filter of a color camera prevents infrared light from forming images. There are two ways to make a color camera sense infrared light. Firstly, switch the filter and block infrared light from entering under visible light conditions. When there is no visible light, the filter can be removed to allow infrared light to enter. Images with good quality can be obtained by using this method, but the cost is high and a certain failure rate will be caused by the switching mechanism. Secondly, a specific infrared channel can be opened on the filter to allow infrared light with the same wavelength as the infrared lamp to enter. Although this method does not increase the cost, the color reduction is slightly poor.
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