The first generation was a card-type attendance machine. In the 1970s, it gradually replaced manual recording attendance. He regularly punched holes in a metal-made card, and then used the photosensitive element and light projection to distinguish the person's number. The 8086 processor. Or 80286 processor. However, the metal piece is easily deformed, causing recognition errors. Coupled with the limitation of resolution, this kind of attendance machine is not widely promoted in coal mines with thousands of people. The second generation is a barcode attendance machine that uses optical principles to project in the beam of a miner's lamp. The attendance machine produces a barcode image, and the worker can use the miner's lamp to illuminate the special attendance probe before going down the well to attend the job. This method is convenient and fast. The earliest used in China is the attendance machine. However, after all, the miner's lamp is a device that often works in harsh environments, so the maintenance is frequent, and the projection of the projection is a problem that binds everyone. The third generation is a magnetic card type attendance machine. Nowadays, the most common attendance machine, like the coal mine worker’s downhole swipe card, has become a habit for everyone. The fourth generation is a biometric identification test machine, which is identified by using human biometrics. This kind of attendance machine can be easily identified as long as one finger, hand support, face is placed on or facing the head. It can prevent the phenomenon of punching cards and improve the management system. The fifth generation is a camera attendance machine and a photo attendance machine, which effectively solves the limitation of biometrics on the environment and the use of people. The combination of smart card management and manual management can be effectively adapted to factories, industrial and mining enterprises and other environments.
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History and type of attendance machine development