Barcode scanner is also a barcode scanner, barcode scanner, barcode reader, barcode reader and barcode scanner. Bar code scanner mainly uses optical principle to read the information contained in the bar code reading equipment, decode the data on the bar code, and transmit the read data to the computer or other equipment by wired or wireless means.

      With the development of society, barcode scanner is widely used in retailers, express logistics, library management, medical code scanning and other industries. At present, the barcode scanner in the market is divided into laser, red light and image, and the classification, principle, advantages and disadvantages and brand of barcode scanner.
      (1) Laser category: The scanning mode of the laser scanner can be divided into single-line laser scanner and multi-line laser scanner. Because laser is the principle of reflection imaging, the laser scanner can only scan the physical barcode, but not the barcode on the screen.
Advantages: high sensitivity, low cost, and readable barcode with small spacing.
        Disadvantages: Laser can't look directly, can only read paper bar codes, needs to align angles (needs a laser line to run through the whole bar code length), can only read one-dimensional codes, and is easy to be damaged when falling.

       (2) Red CCD: Red scanner is also called CCD scanner. Because red CCD scanner is an imaging principle, red CCD scanner can scan bar codes on the screen.
        Advantages: It can be used as a bar code with reflective layer, such as payment identifiable mobile phone screen, etc., without penetrating the bar code.

      Disadvantages: It is difficult to scan short distance and long bar code.

      (3) Image category: Two-dimensional scanner is also called COMS image scanner. Because two-dimensional scanner is the imaging principle, two-dimensional scanner can scan one-dimensional and two-dimensional barcodes such as paper, film and screen.
Advantages: It can be compatible with identifying one-dimensional codes and two-dimensional codes, and can be used as a bar code with reflective layer, such as payment identifiable mobile phone screens, etc. It can be identified without penetrating the bar code, and can be rotated and tilted at 360 degrees, and can be automatically corrected when tilted at 60 degrees.
        Disadvantages: The cost is slightly higher, the cost of scanning small spacing and long bar code is high, and the paper bar code needs additional finishing.

      Compared with these three types of barcode scanner, the image two-dimensional code scanner has strong compatibility and is more favored by users. The scanning functions of the two-dimensional code scanner are as follows: 1. Scan commodity barcodes and two-dimensional codes; 2. Save and share qr code information; 3. Decoding qr code diagram; 4.lbs navigation and positioning; 5. Search of merchant public space; 6. QR code space; 7. Share life information; 8. QR code social entertainment; 9. Paperless movie tickets.
Commercial application scenarios of QR code scanner: such as inventory management, shipment verification, payment, etc. Brands: Delijie, Honeywell, New World, Minde, etc.
        Two-dimensional code scanner self-service terminal application scenarios: such as settlement channel, code scanning payment, gate, queuing number, report printing, express cabinet, ticketing, etc. Brands: Delijie, MASUNG, etc. are good choices.
       Two-dimensional code scanner industrial assembly line application scenarios: such as product traceability, rapid identification of flow status; DPM code has strong reflectivity and small bar code; Brand: Delijie, cognex, Keens and other imported brands.

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