Handheld Bar Code Scanners

Handheld bar code scanners are typically used as inventory or point of sale devices. They are manually passed over bar codes to read data, and function in a near or noncontact capacity.  A wand is typically made from 1/2" stainless steel tubing or from plastic; the optics are in the front with a cord out the back. The wand scanner must be moved by the user's hand across and in contact with the bar code. While the wand is moving across the bar code, the reflected light is converted to electrical signals through a photocell in the wand.  A gun type can be non-contact or near-contact scanner, which generally uses a beam of focused light to read the bar code. The most common form of active non-contact scanner uses a laser beam that is automatically scanned back and forth across the symbol at a high rate. Near-contact scanners utilize a CCD device. Active non-contact or near-contact scanners may be stationary as an option.  Gun type readers can also be equipped with optional fixed mounting.

Bar code scanners, handheld can be configured to recognize a variety of bar code symbologies.  These include, but are not limited to, Codablock, Codabar, Code 1, Code 11, Code 128, Code 16K, Code 39, Code 49, Code 93, Data Matrix or Data Code, EAN, Interleaved 2 of 5, Matrix 2 of 5, Maxicode, MSI/Plessey, NW-7 Code, PLANET, POSTNET, Telepen, UPC, and VeriCode.

Important performance specifications to consider when searching for hand held bar code scanners include resolution, PCS value, scan rate, maximum bar code width, and minimum distance from the target.  The minimum resolution is also sometimes referred to as the "X" dimension. It is equivalent to the narrowest bar or space in the bar code and can be used to determine a bar code's density (number of characters per inch).  PCS stands for Print Contrast Signal, it measures the contrast level between background and bars to be high enough for consistent reads.  The scan rate is the number of scans per second the scanner can differentiate between.  The minimum distance is important for near or non-contact only.  It is the distance the target can be away from the scanner.  Optical head choices include laser or LED/CCD.  Both scanning methods (LED vs. Laser) result in a digital signal that must be translated into recognizable, or computer-compatible data.  Using an algorithm, the decoder identifies and interprets each bar coded message, and transmits that data to the host computer or utilizes it for additional purposes. The term "wedge" refers to any device inserted between the scanner and the terminal that translates the digital signals into usable codes.

Other important parameters to consider when specifying bar code scanners, hand held include user interface options, software interfaces, reading specifications, general features included with the device and environmental operating conditions.

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Part Numbers for Handheld Bar Code Scanners