Summary：The barcode scanner is a device that reads the barcode and converts it into numbers and letters. The barcode scanner is connected to the computer to store the numbers and letters that are decoded by the scanner.
The barcode scanner is a device that reads the barcode and converts it into numbers and
letters. The barcode scanner is connected to the computer to store the numbers and letters
that are decoded by the scanner. The barcode scanner is connected to the computer using
a cable via the serial port or the keyboard wedge. A decoder circuitry is present in the scanner
that is used to decode the barcode image with the help of a sensor.
The barcode is a set of vertical lines and spaces. The lines or bars of the barcode are differentiated
from each other according to the width and spacings of the bars. The barcode includes a start bit,
stop bit and sometimes contains the checksum bit. The checksum bit checks for the accuracy of the
The barcode scanner consists of a laser source and a photo sensor. The scanner decodes the barcode
into electrical signals and gives to the computer. The computer must have a barcode scanner software installed in it. The barcode scanner software helps to convert the electrical signals from the barcode scanner to numbers and letters. There are different types of barcode scanners available which are as follows:
Pen-type Barcode Scanner
The pen-type barcode scanners are pen-shaped and have a light source and a photo diode at the tip of the scanner. The light source
falls on the barcode and the photo diode converts the reflected light of varying light intensity
in a waveform. This waveform is fed to the computer via the cable. The barcode scanner software
converts the waveform to related data. The pentype readers are available in different resolutions
so as to read barcodes of different shapes andsizes. This type of scanner is less expensive and
is easy to maintain.
Laser Barcode Scanner
The laser barcode scanner has the same working like that of a pen-type barcode scanner.
The parts of the laser barcode scanner are different. Laser scanners use laser beams
as a source of light and reciprocating mirror or rotating prism for detecting the reflected
light. The frequency of light source used in the pentype and laser bar code scanner is
same and the light detecting devices like the photo diode and prisms are tuned to the
CCD Barcode Scanner
CCD stands for charge-coupled device and is used in the barcode scanner. This type of barcode scanner
consists of an array of tiny sensors placed at the tip of the scanner.
The tiny sensors generate a voltage waveform and they are sequentially collected
by the barcode scanner and given to the computer for conversion. The basic difference
between the pentype barcode scanner and laser barcode scanner is that the pentype
measures the reflected lightof specific frequency and the laser scanner measures the emitted ambient
light from the barcode. They are widely used in sales applications.