Principle of CCD barcode reader

CCD is an electronic coupling device (Chargcoupledevice), which is more suitable for close-range and contact reading. Its price is not as expensive as a laser barcode scanner, and there are no moving parts inside.

The CCD barcode scanner uses one or more LEDs that emit light that covers the entire bar code. An image of the bar code is transmitted to a row of lights, sampled by each individual photodiode, and detected as "black" or "black" by an adjacent one. White" distinguishes each bar or space, so as to determine the characters of the bar code. In other words, the CCD barcode scanner does not pay attention to reading each "bar" or "space", but the entire part of the bar code, and converts it into an electrical signal that can be decoded.

Advantages: Compared with other readers, CCD barcode scanners are less expensive, but also have a wide range of densities for reading barcodes and are easy to use. It is lighter than a laser barcode scanner, and unlike a light pen, it can only be read by touch.

Disadvantages: The limitation of the CCD barcode scanner lies in its reading depth and reading width, which makes it difficult to read barcodes printed on curved surfaces (such as beverage cans); in some occasions that require long-distance reading, such as warehouse fields, Not very suitable; CCD has poor anti-drop performance, so the failure rate is high; when the barcode to be read is relatively wide, CCD is not a good choice, and barcodes with very long information or low density can easily exceed scanning The reading range of the head makes the barcode unreadable; and in some barcode scanners that use multiple LEDs, the failure of any one of the LEDs will lead to unreadable reading; most CCD barcode scanner has a low first reading success rate and a high error rate.