What is the principle of a barcode scanner

Barcode scanner technology: Commodity barcode coding principles When coding commodities, the following basic principles should be followed: Uniqueness The principle of uniqueness is the basic principle of commodity coding. It means that the same commodity should be assigned the same commodity code, and commodities with the same essential characteristics are regarded as the same commodity; different commodities must be assigned.
When coding commodities, the following basic principles should be observed:
1) Uniqueness
The principle of uniqueness is the basic principle of commodity coding. It means that the same commodity should be assigned the same commodity code, and commodities with the same basic features are regarded as the same commodity; different commodities must be assigned different commodity codes. Commodities with different essential characteristics are regarded as different commodities.
2) Stability
The principle of stability means that once the commodity identification code is assigned, it should remain unchanged as long as the basic characteristics of the commodity do not change. Whether the same commodity is produced continuously or intermittently, the same commodity code must be used. Even if the product is discontinued, its code should not be used on other products for at least 4 years.
3) Meaninglessness
The principle of meaninglessness means that each digit in the commodity code does not indicate any specific information related to the commodity. Meaningful codes usually result in a loss of coding capacity. Manufacturers are better off using meaningless serial numbers when compiling commodity codes.
For some commodities, it may be necessary to know additional information during the circulation process, such as production date, expiration date, batch number, and quantity, etc. At this time, application identifiers (AI) can be used to meet the labeling requirements for additional information. The application identifier consists of 2 to 4 digits and is used to identify the meaning and format of the subsequent data.
What is the scanning principle of the barcode scanner?
Barcode scanners use photoelectric principles to convert barcode information into computer-acceptable information input devices. They are often used in libraries, hospitals, bookstores, and supermarkets as input methods for rapid registration or settlement. Read the barcode information directly on the screen and input it into the online system.
1. The barcode scanner is a device used to read the information contained in the barcode. The structure of the barcode scanner is usually the following parts: light source, receiving device, photoelectric conversion component, decoding circuit, and computer interface.
2. The basic working principle of the barcode scanner is:
The light emitted by the light source is irradiated on the barcode symbol through the optical system, and the reflected light is imaged on the photoelectric converter through the visual system, so that it generates an electrical signal, and the password is amplified by the circuit to generate an analog voltage. The reflected light on the symbol is proportional, and then filtered and shaped to form a square wave signal corresponding to the analog signal, which is interpreted by the decoder as a digital signal that can be directly accepted by the computer.
3. Ordinary barcode scanners usually use the following three technologies: light pen, CCD, laser