Why QR code has 3 dots?
The Answer: They're Finder Patterns
The three dots on a QR code are known as a finder pattern. The dots play a crucial role in helping smartphones' cameras recognize the QR codes. Not only that, but the dots inform the smartphone of the code's orientation.The phone's camera needs to read the code at the right angle. The two dots on the top of the code help the camera find the right angle. This is why the dots are called finder patterns.
If a QR code was not printed in the correct position, then the phone's camera would know that the scanner needs to be adjusted in order to properly read the code. In short, two dots have to be on the top in order for the phone to read the code.
Let's say QR codes had four dots, then this means a phone's camera would have no way of telling whether or not it was properly scanning the code. It's important for the phone's scanner to know whether the QR code is the right way, rotated clockwise or anticlockwise or upside down. The bottom line is three dots make it very easy for phones to scan codes.
Allows Damaged Codes To Be Scanned
Another reason why there are three dots on QR codes is because they allow codes to be read, even in the event that the code has been damaged or distorted. If there were less or more dots, then you would not be able to scan the code. There are several reasons why a code can be distorted or damaged, but as long as it has three dots, it should still work properly.That is why there are three dots on QR codes. If someone is creating a QR code, then it's important for them to do it properly by making sure it contains three dots. If they use a code that doesn't, then whoever scans the code will not be directed to targeted destination because their phone's camera won't be able to properly scan the code.