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Further, the CCD has a limited width, and will not read bar codes that thermaltransferprinter are wider than the face of the input device. It is largely popular for use in point of sale applications. The laser scanner is perhaps the most popular bar code input device. A laser scanner need not be close to the bar code to do its job. A standard range laser thermaltransferprinter scanner can read a bar code from about 6 to 24 inches away, and a long range scanner can read one from perhaps 2 to 8 feet away. An extra long-range device can even read a bar code 30 feet from the device. Laser scanners vary in price from $200 to $2,000 and come in a variety of models. A decoder may be located inside or outside the input device. An internal decoder takes up less space and is less expensive, but it is also less functional. An external decoder is a bit more expensive, but is also more functional, with the capabilities to manipulate data and accommodate multiple input devices on a single port. The "wand" is the simplest and least expensive input device available. It is durable and contains no moving parts. It must, however, come into contact with the bar code, which can present a challenge. If a bar code must be read more than once, it may become smeared or damaged and, in essence, unreadable. Also, a wand thermaltransferprinter is "human powered," which means it must be held at the proper angle and moved at the proper speed. For these reasons, a wand is the best choice when cost is the largest determining factor. The CCD, or "Charge Couple Device," is another common input device. A CCD is a very "aggressive" instrument, with a high ability to read bar codes quickly and easily. But it has thermaltransferprinter two primary limitations. First, it has a short "read" range, and thermaltransferprinter must be held no more than 1 to 3 inches from the bar code.
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