The lens is equivalent to the human eye lens, lens, seeing no object; If there is no lens, the camera output image is the white one, no clear image output. The human eye muscles can not be stretching the lens to its normal position, the myopia is often said that the scene in front of blurred; camera and lens with a similar phenomenon, when the image becomes unclear , you can adjust the back focus of the camera, changing the distance of the CCD chip with lens datum can be blurred image becomes clear. How can only think that the selection of a suitable camera lens? The following Chinese machine vision Mall branch recipe for you:

1, to the distance of the target being monitored according to the camera, fixed focus lens (Fixed Focal Lens) focal length. Distinguish from the focal length on the short focal length wide-angle lens, the focal length standard lens, long focal length telephoto lens. Lens focal length is usually used to represent the lens aperture is generally said with F, F value to the lens focal length / aperture ratio of d to measure, F = f / d, each lens are marked with the largest F value.

2, the camera lens specifications of CCD target surface size (1/2 "6.4hX4.8υ 1/3" 4.8hX3.6υ 1/4 "3.2hX2.4υ) corresponding to the If the lens size inconsistent with the camera CCD target surface size, the viewing angle will not meet the design requirements, or the occurrence of the screen outside the focus.

3, the camera horizontal visual degrees and vertical visual degrees between the camera CCD target surface the size hXυ and lens focal length f the following relations: horizontal visual degrees 2arctan (h/2f); vertical visual degrees 2arctan (υ/2f).

4, the lens auto iris (auto the Iris) and manual aperture (manual the Iris) of the points. Auto iris for light to be illuminated object is much more varied occasions, manual iris for the Office of the light stability of the illuminated object. Auto iris lens there are two kinds of drivers: one for the video input Video driver (with Amp), it will be a video signal and power from the camera transported to the lens to control the aperture on the lens, this video contains input type lens amplifier circuit, which camera coming from the video signal conversion pairs iris motor control, and the other called the DC input type (DC driverno Amp), which uses the camera on the DC voltage to the direct control of the aperture, the lens inside contains only the current meter aperture motor, amplifier circuit in the camera.

5, the lens has a C-type and CS type C-type lens installed in more than a CCD camera and lens ring of 5mm to adjust the aperture value. C-mount camera can be used CS-type lens, CS mount cameras can not use C-type lens.

6, the zoom lens in a lens to the lens focal length to change, so you can zoom in or out monitoring targets within a certain range. Typical specifications of the optical zoom there are different grades such as 6 to 20 times, and the most common power zoom lens (Zoom Lens).

7, zoom / zoom lens (Vari Focal Lens) is a function of zoom with the zoom lens, the focal length is continuously variable, distant objects amplification, but also to provide a broad view of monitor width increases. Machine Vision mall supply many of the world's well-known brand lenses for industrial applications, such as COMPUTAR, AFT , etc., for more information and details of machine vision products, please visit the Machine Vision the mall www.china-vision.com.cn Advisory hotline: 4000 - 400-816.

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