What bar code scanner do I need? Laser, CCD or Imager?

Bar code scanners - Laser, CCD or Imager?


Defining your application will enable you to make a choice between the different scanning technologies on offer:

Laser application
A laser application is defined by requiring a reading distance of more than 30 cm (non contact) and a depth of field of 5M or more.

CCD application
A CCD application is defined by requiring a reading distance from near contact to 30 cm (instinctive reading range). Reading damaged or poorly printed bar codes and reading bar codes under plastic film.

Imaging application
An imaging application is defined by requiring the digital image capture of one or two dimensional (2D) bar codes and / or images.

Products - Bar code scanners

Background

Scanning technology has been improved over the last 5 years and now consists of Laser, short / long range CCD and Imager scanners.

Laser scanner - An optical bar code reading device using a low-energy laser light beam as its source of illumination. Laser technology has a built in laser diode to emit the beam which is then deflected by an oscillating mirror. Laser technology is capable of reading over a range of distances with large depths and extreme scan angles. Laser technology is capable of reading many barcode formats.

CCD scanner - An Charge Coupled Device using an array in the form of a pulse height-modulated electric signal to scan the barcode.

CCD readers normally use light emitting diodes (LEDs) to produce the light beam and a charge coupled device array (CCD) to read the reflected light. When using CCD technology you must take into consideration the fixed reading distance, the depth of field and the angle of the scan. CCD readers are usually linear scanners, with a thicker scan beam than the laser readers.


Imager scanner - Uses a linear imaging sensor to take an image of the barcode.

Imager technology uses a small camera to capture 1d and 2d barcodes. It then decodes the barcode using digital image processing. The area to read is usually illuminated by LEDs and the aiming mark is provided by a laser.


Applications

• Retail
• Office
• Warehousing
• Manufacturing
• Document processing
• Inventory Control