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Indicators For Optical Lenses

Danyang Youjie Tools Co.,Ltd | Updated: Oct 16, 2017

The intrinsic index describing the quality of lens imaging is the optical transfer function and distortion of lens, but for the user, it is only the spatial resolution of the lens, and the number of black and white stripes that can be distinguished by each millimeter is the unit of measurement, the formula is: the height of lens Resolution N 2,180/format. Because the camera CCD target size has been standardized, such as 1/2-inch camera, the target is wide 6.4mm* height 4.8mln, 1/3-inch camera for width 4.8mmx High 3. 6mm. So for 1/2-inch format CCD target, the minimum resolution of the lens should be 38 pairs of line/, 1/3-inch format camera, the lens resolution should be greater than 50 pairs of lines, the smaller the target of the camera, the higher the resolution of the lens.Optical Lenses

First, depending on the distance of the camera to the monitored target, the focal length of the lens is chosen, and the lens focal length f is determined, then the visual field is determined by the camera target. The amount of light in the lens is measured by the ratio of the focal length of the lens to the aperture, with the F as the mark, the maximum f value on each lens, the amount of the flux is inversely proportional to the square of the F value, the smaller the F value, the greater the aperture. Therefore, depending on the degree of light change of the monitored part, the manual aperture or the automatic aperture lens should be chosen.Optical Lenses

In addition to optical amplification, electronic digital amplification can be applied to enlarge the magnification. In the electric telescopic lens, the aperture adjustment has three kinds, namely: automatic aperture, DC drive automatic aperture, electric adjustment aperture. The focus and the zoom adjustment, only electric adjustment and preset two kinds, electric adjustment is driven by the motor in the lens, and the preset is to adjust the stop bit beforehand through the potentiometer in the lens, so that the process of the image must be adjusted, and can be accurately and quickly positioned. In the spherical dome integrated camera system, most of the telescopic lenses with preset bits are used. Another interest for users is the fast focus function, which consists of a focal system and an electric zoom feedback control system.Optical Lenses



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