Barcode Scanners Buyers Guide - An Introduction
A barcode scanner also known as barcode reader is an electronic device that is capable of reading barcode information. The main components of a barcode scanner are a light source, lens and light sensor to convert optical impulses to electrical impulses. The barcode scanners also come with a decoder circuit that manipulates the image data produced by the light sensor and transmits the barcode information to scanner's output.
The barcode represents numbers, alphabets and alphanumerics in terms of white and black bars of varying widths. A barcode scanner reads this information and converts it into electrical pulses. Since each strip represents a number, this electrical pulse can be digitised and displayed as readable text.
The barcode is illuminated by red light from the illuminating system; the illuminating system could be single point LED, linear multiple LED, Laser or LED Imager depending on the scanner type.
Single point LED: In single point LED illumination system, the light source is either a single or pair of LEDs that get focussed through a ball type opening. Since it is a single point LED system, , the operator drags the illumination wand over the barcode in case of barcode wand or swipes the card through provided slot in case of swipe readers.
Linear Multiple LED: This system employs multiple LEDs in a line lighting the entire width of the barcode and is used with CCD barcode scanners.
Laser: Laser illuminating system employs a single point red laser diode whose point of light is expanded by oscillating the laser into a stationary mirror or projecting the point into an oscillating mirror. This is the most popular system as the working distance achieved by this system is greater than the systems. The distance covered is between 1” and 18”; when laser power is increased with subsequent decrease in oscillating angle the distance can go over 20 feet.
LED Imager: The linear and full imager is very much like a CCD device but with significant changes. In linear imagers, the illumination is increased by using high light LEDs and the photo cells in the sensors are more sensitive. In case of full imagers, high intensity LEDs illuminate a square scanning area. The sensors search the square target for barcode information.
This light gets reflected by the barcode and the reflection is sensed by a photo detector. The photo sensor creates an analogous signal with fluctuating voltage. This fluctuation occurs as white bars reflect light while black bars absorb the red light. The image sensor technology varies with the illumination system; however, the output remains the same.
The generated voltage is sent to the converter to be converted into digital signal. This signal is passed on to the decoder to translate the signal into readable texts.
Barcode scanners can be classified into different types based on housing. They are described as follows.
Pen or Wand Type: Pen or wand type barcode readers resemble a pen. It has a an LED light and a photodiode in its tip which the operator drags over the barcode. Eg. SCANTEAM 2380 of welch allyn barcode scanner
Hand Held: These are the most prevalent kind of barcode scanners usually employing laser. However LED and CCD technology in this kind of barcode scanner are gaining popularity. Eg. Heron D130 of Datalogic barcode scanners, SP1000 of fluke barcode scanner and OPL6845 of Opticon barcode scanners.
Handsfree model: Some barcode scanners like handheld barcode scanners come with a stand so the scanner body can be fixed on top of the stand. A few models of metrologic instruments barcode scanners brands.
Stationary Scanners: Stationary barcode scanners are barcode scanners that are secured in a place and the product label is moved over the glass that secures the barcode scanner.
Fixed position Scanner: Stationary and fixed position scanner sound very much alike but are fundamentally very different. Stationary scanners do not move at all while fixed position scanner is attached to an arm that moves in a well structured way.
Wireless/bluetooth Barcode scanners: cordless barcode scanners, as the name implies, do not use a cord or a wire and use wifi or bluetooth technology for establishing connections. Eg. WWS800 industrial barcode scanner and SR61B intermec technologies barcode scanner.
Buying a reliable barcode scanner is a time consuming task that requires a lot of research. When you want to buy a barcode scanner, do as much research as possible and find out what's new in the UK market for barcode scanners. Understand what you require from your barcode reader and see what other facilities will enhance your work environment. Make sure that you do not buy scanners with features that you do not require. For instance, if you will only be scanning a 1D barcode, there is no point in purchasing a barcode that will also read 2D barcode.
Check out different brands and models before settling for one, this will save you a lot of money. For instance Welch Allyn Barcode Scanners are cheaper than many other barcode scanner brands. Also read reviews by users and experts to get a clear picture of the barcode reader’s reliability.
All you need to do to get a perfect barcode reader is to do a lot of research and be well informed before you decide on buying a particular product.