Megapixel lenses used in closed-circuit monitoring basic knowledge
Published | 2014-06-25 12:19:26
In Megapixel security monitoring market, closed-circuit monitoring system, also known as a camera or video camera CCD (Charge Coupled Device) that charge-coupled device. Strictly speaking, the camera lens and the camera is a general term, and in fact, most of the camera and lens is later separated from the user according to the size of the target object and the camera and the object, obtained by calculating a focal length of the lens, each user The lenses are based on the actual needs of the case may be, do not think that has lens camera (head) on. The main components of the camera sensor is CCD, it has a high sensitivity, distortion, long life, anti-vibration, anti-magnetic, small volume, no blur characteristics, CCD is a charge coupled device (Charge Couple Device) for short, it can The light changed and the charge storage and charge transfer, the charge can be stored in the removal of the voltage changes, so is ideal for imaging element. Is replaced by a new type of camera tube sensor devices. CCD working principle is: the subject is reflected light, transmitted to the Seiko lens, lens focus by ZLKC onto the CCD chip, CCD according to the intensity of light corresponding to the accumulation of charge, through the periodic discharge, said electricity generated picture depicting signal, after filtering, amplification processing, through the output terminal of the camera with a standard composite video output signal. The standard video signals with home video recorders, VCD machines, home video camera's video output is the same, so it can be connected to a TV or video viewing. CCD camera CCD chip as the selection and classification of the human retina, is the core of the camera. There is no capability of manufacturing, the market most of the camera is used in Japan, SONY, SHARP, Panasonic, LG and other companies produce chips, and now South Korea also has the ability to produce, but the quality would rival. Because when the chips produced using different grades, different ways to get the manufacturers and other factors, the effect is very different CCD acquisition. At the time of purchase, you can take the following method detection: power, connect the video cable to the monitor, close the lens aperture, whether there are bright spots all black when watching images on the screen are not so big snowflakes, these are the most simple and direct detection of the CCD chip methods, but no other special equipment. Then you can open the aperture, look at a still life, if it is color camera, preferably a colorful object ingestion, the image on the monitor to see whether the cast, distort, color or grayscale is smooth. Good CCD can be a good scene to restore color to make objects appear clear and natural; while the image defective products will have a color cast phenomenon, even in the face piece of paper, the image will be displayed in blue or red. Because individual CCD workshop dust, CCD target surface impurities will, in general, the impurities will not affect the image, but in low light or microscope camera, the fine dust can also cause adverse consequences if used Such work must be carefully selected.