Often we are asked whether it makes sense to simply use the built-in camera of handy mobile phones to handle scanning. Camera-based scanning of mobile phones adds little to no incremental cost, but is limited by the efficiency and reliability. This is a function of the distance between the handy camera and the barcode, size, type and lighting conditions. In warehouses with bulky and heavy items, being able to lift items or move the handy to properly frame the barcode is far less desirable than simply scanning with a wrist or finger-worn wearable barcode scanner with the arm extended. This becomes especially cumbersome in high volume environments.
Barcode scanning or reading are a fast and economical way for automatic article identification. Nearly all barcode scanners or readers contain decoder circuitry that can analyze the barcode’s image data provided by the sensor and sending the barcode’s content to the scanner’s output port. However, the source of light, lens, and sensor can be different which are optimized for particular application, therefore the selection of a right model of scanner or reader is critical. Before to start, think about these questions:
- Do you need wired or wireless scanner?
- How frequent or intensive do you need to scan barcodes?
- Are you performing multiple transactions at once?
- Do you need to read 1D, 2D barcodes or both?
- Are you scanning barcodes or utilizing RFID?
- How much memory does your device need to have?
- Do you have the demand for a specific scan engine?
- What distance do you need to scan?
- Do you need a wearable data terminal?
- Do you need a mobile solution?
- Are you on a network and want to process real-time?
- Do you have security limitations and requirements?
- Is your environment hazardous?
1D Laser-type Scanner
Disperses a laser dot into a thin solid line and in turn projects it onto a barcode. The laser beam repeatedly moves from left and right, hence the scanner has moving parts. The laser scanner is perhaps the most popular barcode input device.
Advantage: They can scan in direct sunlight (in most instances), and project a thin, very precise laser beam onto the barcode. Using laser scanners allows for the reading of wide and distant bar code labels.
Disadvantage: Struggles to scan small barcodes or high resolution barcodes (Not as good ion as Linear Imager scanners), and has moving parts that can break, and it is also not possible to read objects on screen.
1D CCD-type Scanner
Light detectors aligned in a single row eluminates the barcode, and an actual lens in the scanner reduces the full barcode image onto the imaging sensor. CCD barcode scanner technology is based on camera imaging technology.
Advantage: This method is great for capturing very high resolution details along with widened color space. It can also scan folded lines, objects on screen, and has no moving parts.
Disadvantage: First, it has a short “read” range, and must be held no more than 1 to 3 inches from the barcodes. Further, the CCD has a limited width, and will not read barcodes that are wider than the face of the input device. It is largely popular for use in point of sale applications.
2D Imager-type Scanner
Based on the same technology as CCD scanners (imager), but has a longer range, comparible to Laser barcode scanners. These devices cannot only read matrix codes, but also 1D and other 2D Symbologies. An imager operates like a camera taking a picture of the image.
Advantage: Able to scan smaller barcodes than lasers scanners. Genreally more rugged than Laser scanners because they have no moving parts.
Disadvantage: Usually can’t scan in direct sunlight.
For short range scanning: CCD scanners are a good choice if price is an issue and occasionally scanning barcodes.
For long range scanning: Laser scanners are geenrally the best choice, with some rugged scanners able to scan up to 100 meters long.
Laser vs Linear Imager: For the vast majority of applications it won’t make a difference choosing between a Linear Imager or a Laser, unless you need to scan really small barcodes or barcodes on screen (use Linear Imager), or you have to scan in sunlight (use Laser).
Portable Data Terminals
Sometimes you must bring the computer to the barcode, particularly to handle jobs such as warehouse inventory control or freezer applications. A portable data terminal, a fully programmable hand-held computer, is necessary in such instances. When a scanner device is integrated into the unit, you have created a powerful data collection device. The most common implementation is an integrated 1D laser scanner, but 2D imager scanners are now being more popular.