When it comes to automatic box labelingsystems, the use of a bar
We use two separate bar code scanners to do two different jobs. The first is referred to as a “pre-identification” scanner, and the second is called a “verification” scanner.
The function of a pre-identification scanner is to scan a label that has been previously applied to a box or pre-printed on a box to let the system controller know what product is contained in the box.
The verification scanner’s job is to scan the label that the system printed and applied to the box to be sure that it is a good, readable label.
With today’s technological advances, barcode scanners are being replaced with vision-based sensors. These sensors essentially work by taking a picture of the label, and by using the processing power of the sensor itself, it is able to read the barcode on the label and send that information to the system controller.
This type of sensor offers many advantages that were not available with the laser-based scanners:
- Ability to read both 1D and 2D codes
- Ability to store every scanned image to a file on the controller
- Ability to view images from several different sensors in real time
- Ability to grade the quality of each image, which allows the controller to signal preventative maintenance
- Better ability to read damaged codes
- Allows the use of multiple filter settings
This lets the sensor look at the image in a different way. For example, if the sensor is going to have 10 chances to read the barcode, you can set up the sensor to try 8 times with a setting that works best under normal circumstances, and if it fails to get a good read, it can look at the label a different way for the last 2 chances.
With these advances in technology, this type of sensor offers a lot of added functionality over standard barcode scanners for essentially the same cost.