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Handheld Barcode Scanners
Handheld barcode scanners are usually "corded" scanners that have a cord connecting them to a PC. These scanners are called by different names like hand held scanner, wedge scanner or barcode gun.
When you place handheld barcode scanners to face a barcode, they sense an optical image of the code and convert this signal into electrical signals, which stand for the code seen by the devices. A barcode reader consists of a barcode scanner as well as a decoder. During the initial stages of its development, the barcode scanner and decoder were two different equipments. However, handheld barcode scanners these days use a barcode scanner having an in-built decoder. When the scanner reads the barcode effectively, your PC shows the data. This data on your computer may appear as if you have typed it there. By default, handheld barcode scanners are built in such a way that they send a Carriage Return after they have read the text. It is pretty similar to the process where you press the Enter button after keying in the number on your PC.
Handheld barcode scanners generally make use of two main types of scanning technology namely laser line scanner and imaging technology. In the former case, a red line is projected from the laser line scanner. This line actually originates as a dot, which is produced by a laser diode. This dot gets changed to a line when the light is projected into a mirror that vibrates. After this step, the user adjusts the orientation so that the line remains perpendicular to the codes’ vertical bars. Once the sensor in the scanner has read the reflected light, the information is sent to the decoder. The decoder changes this data into ASCII text and sends it back to the host or PC using the cord.
In case of imaging technology, a red light of rectangular or square pattern is projected by LED's having very high power. Like laser line scanners, the scanners here sense and read the reflected light, which in turn gets converted into ASCII text. The durability of these scanners is superior to their laser counterparts. Some models can even read a barcode irrespective of their orientation. So, it is of no importance whether the beam is perpendicular or not to the vertical bars of the barcode.
While selecting handheld barcode scanners, you need to consider your budget, the applications that you require and the performance that you expect from it. So, make an informed choice keeping these factors in mind and make the most of your scanner.
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