Types of Technology in Barcode Scanners
According to the type of the technology that they use, the barcode readers are divided into the following groups:
- Pen type readers are the simplest scanners and have to be put in close contact with the barcode; the reader analyzes the reflected light with the help of a photodiode, which is placed next to the light source of the reader.
The diode generates waveform, which mimics the barcode pattern and this waveform is sent to a decoder. - Laser scanners use single or multiple laser beams as their light source and just like the pen type scanners, use photodiode that interprets the reflected light.
The laser readers are fast, extremely accurate and certain models can scan barcodes from a great distance; they also use decoders that translate the received information into text. - CCD readers have hundreds of small light sensors, instead of just one; with the help of these sensors, placed in a row, the CCD scanners take linear picture, which is interpreted quickly.
The light, measured by these readers, is the ambient light from the barcodes, while most other types of readers measure the reflected light. - The camera-based scanners are a new generation of barcode readers, which use cameras instead of photodiodes; the tiny video cameras that are used by these readers work on the same principle as the CCD readers, but instead of light sources arranged in a row, they have hundreds of light sources that are ordered in two-dimensional arrays.
The camera-based 2D readers that are capable of scanning labels that are wrinkled and even damaged and can also process items that are moving, which makes them ideal for businesses that have to process large amount of items in a short period of time. - Omni-directional barcode readers are, as the name indicates, using light source which emits light in many different directions.
The light source is almost always a laser and due to the pattern of beams that they use, these readers can read barcodes that are placed at any angle.
The Omni-directional scanners can read labels from just a few inches and these are the scanners, found in most supermarkets today, but there are industrial models that are capable of scanning barcodes from a few feet away.
These types of scanners are also able to read dirtied, wrinkled, and even damaged labels. - Cell phone cameras.
Even though cell phone cameras aren't built for specifically reading barcodes, with the help of specialized software applications, they can be used as barcode readers as well.
Once read, the 2D barcode labels can be translated not only into plain text, but images, sounds, and videos as well.
This makes cell phone cameras ideal for reading movie, music, and DVD catalogs, but they are suitable for reading regular barcodes on various products in the supermarkets as well.
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