What are Barcode Scanners?

Bar code scanners, also known as bar code readers, bar code scanners, bar code scanners, bar code scanners and bar code readers. It is a reading device used to read the information contained in a bar code. Using the optical principle, the content of the bar code is decoded and transmitted to a computer or other device via a data line or wirelessly. Widely used in supermarkets, logistics express, libraries and other barcode scanning of goods and documents.

Barcode scanner

Bar code scanners, also known as bar code readers, bar code scanners, bar code scanners, bar code scanners and bar code readers. It is a reading device used to read the information contained in a bar code. Using the optical principle, the content of the bar code is decoded and transmitted to a computer or other device via a data line or wirelessly. Widely used in supermarkets, logistics express, libraries and other barcode scanning of goods and documents.

Chinese name

Barcode scanner

Foreign name

bar code scanner

nickname

Bar code reader, barcode scanner, etc.

Application area

Supermarkets, logistics and express delivery, libraries, etc.

Bar code scanners are often called bar code scanners / readers. They are devices used to read the information contained in bar codes. They can be divided into one-dimensional and two-dimensional bar code scanners. The structure of a barcode scanner is usually as follows: light source, receiving device, photoelectric conversion component, decoding circuit, and computer interface. The basic working principle of the scanning gun is: the light emitted by the light source shines on the barcode symbol through the optical system. The reflected light is imaged on the photoelectric converter by the optical system, and interpreted by the decoder as a digital signal that the computer can directly accept. Divide one or two-dimensional barcode scanner classification. Can also be classified as:

Barcode scanner aka

Common bar code readers usually use the following four technologies:

Barcode scanner has the following features

Bar code scanners are widely used in commercial POS cash register systems, express warehousing and logistics, books, clothing, medicine, banking, insurance and communications, and other areas of demand. Keyboard interface, USB interface and

Different products have different parameters. For details, please visit the relevant scanner manufacturer's website.

There are many types of bar code scanners, and the following are common:

There are four common interface types for barcode scanners:

At present, there are mainly four kinds of photosensitive devices used in barcode scanners on the market: photomultiplier tubes, silicon oxide-isolated CCDs, semiconductor-isolated CCDs, and contact-type photosensitive devices (CIS or LIDE).

The mainstream is two types of CCDs. The principle is simply: several thousand to tens of thousands of phototransistors are integrated on a silicon single crystal. These phototransistors are divided into three columns and covered with red, green and blue color filters, so as to achieve Color scanning. Compared with the two types of CCDs, silicon oxide isolated CCDs are better than semiconductor isolated CCDs. Friends who are familiar with physics naturally know the reason. In short, the leakage between semiconductor CCD triodes will affect the scanning accuracy. Isolation with silicon oxide will greatly reduce the leakage (this is an insulator). Of course, it is best to add temperature control, because whether it is a semiconductor or a conductor, Both are temperature sensitive, and conductivity will generally increase at elevated temperatures. At present, most of the mainstream markets are semiconductor-isolated CCDs. Silicon oxide-isolated CCDs are relatively rare, obviously because of higher costs. If you want to understand the effect of a barcode scanner, it is very important to understand what kind of optoelectronic components the barcode scanner uses, even if it is the same as the semiconductor isolation quality.

Contact type photosensitive device, the photosensitive material it uses is generally cadmium sulfide we use to make photoresistors, and the production cost should be much lower than that of CCD (the same accuracy CIS barcode scanner on the market is always cheaper than CCD barcode scanner Many are for this reason). The short scanning distance, low scanning clarity, and sometimes not reaching the nominal value, and temperature changes are more likely to affect the scanning accuracy. These are the fatal problems of this type of barcode scanner. Friends who are familiar with physics should know that the leakage current between the resistances of cadmium sulfide is larger than that of semiconductors, which also reduces the accuracy.

Photomultiplier tubes, photosensitive materials are mainly oxides of metal cesium. His scanning accuracy is the best even affected by temperature and noise, but the price is also the most expensive. Ordinary users like me are just dreaming about it. The price is too expensive. We will skip its specific technical features here.

The photoelectric device of a barcode scanner is an important factor that determines its performance. Others such as control circuits and software are also important. Understanding this information directly can be difficult. We often can only understand limited content (business secrets). When we judge the performance of a bar code scanner, we only know it by actual operation and evaluation software.

A bar code is a group of bars and empty symbols arranged according to a certain coding rule, which is used to represent information composed of certain characters, numbers and symbols. Bar code system is composed of bar code symbol design, production and scanning

The resolution of a barcode scanner is equal to the resolution of its optical components plus the resolution obtained from processing and analysis by hardware and software from ^[1] . Optical resolution is the actual number of light spots that can be captured by the optical components of the barcode scanner per square inch. It refers to the physical resolution of the barcode scanner's CCD (or other optoelectronic device) and the true resolution of the barcode scanner. Rate, its value is the value obtained by dividing the number of pixels that can be captured by the photoelectric element by the maximum scannable size of the barcode scanner level. Optical scanning and output are one-to-one. What is scanned is what is output. After processing by computer software and hardware, the output image will become more realistic and the resolution will be higher. Most bar code scanners currently on the market have software and hardware expansion functions for resolution. Some bar code scanner advertisements write 9600 × 9600 DPI. This is only the maximum resolution obtained through software interpolation, not the true optical resolution of the bar code scanner. So for a barcode scanner, its resolution has optical resolution (or optical resolution) and maximum resolution. Of course, what we care about is optical resolution. This is the hard work. We say that the resolution of a barcode scanner is as high as 4800 DPI (this 4800 DPI is the sum of optical resolution and software difference processing), which means that when an image is input with a barcode scanner, it can be collected on a 1-inch-inch scan 4800 × 4800 pixels. Scanning area of 1 inch square, the image size after scanning with 4800DPI resolution is 4800Pixel × 4800Pixel.