11/09/2023
Barcode scanners primarily detect the contrast between the black bars and the white spaces in a barcode, which allows them to decode the information. When scanning a barcode, the scanner emits light, typically from an LED or laser source, onto the barcode. The light reflects back into a photoelectric cell or sensor.
The key principle here is that the white spaces reflect more light, while the black bars absorb or reflect less light. This contrast in light levels is what the scanner reads to distinguish between the bars and spaces. When the scanner detects a transition from a dark bar to a light space or vice versa, it registers this change as data. By analyzing the pattern of these transitions, the scanner decodes the information encoded in the barcode.
