How Does a QR Code Scanner Work?

The appearance of QR code scanners

QR (Quick Response) codes are alphanumeric matrices that can be decoded by camera phones and mobile applications. Created by Denso Wave, they can be scanned using near field communication (NFC) or barcode scanners to retrieve digital content such as text, contact information, and website links, among others. QR codes can contain any type of data. They are made up of small squares that cannot be read by the human eye. QR codes are similar to barcodes in that they can be recognized by QR code scanners, but their squares are wider instead of narrow lines. The QR code format specification was established by the Japanese Industrial Standards Committee (JISC) in 1994. It assumes that readers will access a URL to obtain further information or content. QR codes can contain up to 4,296 alphanumeric characters in one area, which is relatively larger compared to other two-dimensional barcodes like Aztec and Micro PDF417 (which can only accommodate 2,000 and 1,659 characters, respectively).

The working principle of QR code scanners

A QR code scanner is a device that can read barcodes. When the smart barcode reader is accustomed to scanning QR codes, it can only read the graphical part of the code and not the encoded information within it. The working principle of a QR code scanner is to capture data from an image and convert it into text. It uses pattern recognition technology. The scanner converts the pattern of the image into lines that can be read as text. The black and white dots on a QR code are too small for the human eye to see, but they provide enough information for the scanner to convert them into text. Due to its artificial intelligence capabilities, the scanner can also decode colored text images. Many people are aware that they cannot read characters printed on labels due to the size of RFID tags. However, this is not the case with QR codes. Readers can still read them even though they are relatively smaller compared to the pixel width on standard mobile screens. They are black and white, but humans can still read them relatively quickly without any training.

Using a QR code QR scanner allows for the reading of QR codes, but it is more complex than using the human eye. A typical QR code scanner works by using linear, black-background-white-text or white-background-black-text linear scanning patterns. There are several patterns on QR codes for different purposes. They can be appropriately detected by the scanner's camera with white light, meaning they are not invisible to the human eye. The speed of a QR code scanner is very fast, as it only uses the camera to capture the image. However, they cannot translate the received information into text. For this, the QR code scanner must have artificial intelligence capabilities to convert any image into text.