Of the three hand held technologies available, laser scanning is the most flexible, but also the most expensive. Scanners are often gun shaped, firing a scanning laser beam when the trigger is squeezed. Usually a laser diode is used as the light source. The beam is reflected off the barcode and back into the gun through a large lens to a photo detector. A moving mirror arrangement is used to scan the beam at a constant speed. With this method, codes can be scanned from a distance and the size of the code is not critical as with CCD scanners.

A typical maximum reading distances for a laser scanner are 30 - 90 cm although long range versions are available which can read in excess of 10 metres. However, the greater the distance, the larger the code must be, and the better the print contrast. As laser scanner range increases, so does cost. In practice, scanning range is normally limited by the size (or resolution) of the barcode. Lasers are often used in portable applications where codes are not easily accessible, or in fixed positions such as DIY shop checkouts where the goods are too bulky to be positioned close to the scanner.

Scanner Cable Connections

USB

Our most popular connection method. The majority of PC’s now have at least one USB port.

A USB cable will send data to the PC in the form of emulated keystrokes (as if you were typing on your keyboard) this means data will be displayed on your screen wherever your cursor is.

USB is a simple “plug and play” connection method which rarely requires any configuration and does not need any additional software or drivers.

The cable will draw its power from the USB port meaning unsightly additional power supplies are not required.

Keyboard wedge

A popular connection method – Please ensure that your PC still has a keyboard port as some new PC’s are only supplied with USB.

A Keyboard wedge (otherwise known as PS2) interface sends data to the PC in the form of emulated keystrokes. This means that scanned data is displayed wherever the cursor is on your PC screen. Keyboard wedge (PS2) cables are “Y” cables meaning that they have an extra fly lead which allows you to plug in both the PC keyboard cable and the scanner keyboard wedge cable into the keyboard port at the back of your PC.

The cable will draw its power from the keyboard port meaning unsightly additional power supplies are not required.

Keyboard wedge (PS2) is a simple “plug and play” connection method which rarely requires any configuration and does not need any additional software or drivers.

RS232 (serial)

Most computing devices have an RS232 interface, some are specifically modified for scanning. A standard RS232 interface will not provide a 5v supply typically required to power a hand scanner, so an external power supply will be required.

Customers tend to choose RS232 if they need to have control over what happens to the data once it has been scanned or if they have a specific application which is written to pick up data from the serial port.