(1) Fingerprints

Fingerprints have been used in ancient my country to replace signatures and stamps to prove identity. It can be roughly divided into three basic types: "bow", "skip" and "dou", which have characteristics that are different for each person and remain unchanged throughout life. Fingerprint recognition is currently the most mature, convenient, reliable, non-destructive and cheap biometric technology solution and has been widely used in many industries.

Advantages: First, they are highly specific and complex: fingerprints are unique features of the human body, and their complexity is enough to provide sufficient features for identification. The second is high reliability: if we want to increase reliability, we only need to register more fingerprints and identify more fingers, up to ten, and each fingerprint is unique, and the user will Direct contact with the fingerprint capture head is the most reliable method of reading human biometrics. The third is fast speed and easy to use: scanning fingerprints is very fast and very convenient to use; the fourth is small equipment and low price: the fingerprint collection head is more compact and can be easily combined with other equipment, and with the advent of electronic With the rapid development of sensor chips, their prices will also become cheaper.

Disadvantages: The fingerprints of some people or groups have very few fingerprint features, so it is difficult to image. In addition, since the current fingerprint identification technology does not store any data containing fingerprint images, but only stores the encrypted fingerprint feature data obtained from the fingerprint; every time a fingerprint is used, the user's fingerprint imprint will be left on the fingerprint collection head. , and there is a possibility that these fingerprint traces can be used to copy fingerprints.

(2) Palm print

Palm geometry is based on the fact that almost everyone’s hand shape is different, and the shape of the hand changes when a person reaches a certain age. After that, no more significant changes occur. When the user places his hand on the hand reader, a three-dimensional image of the hand is captured. Next, the shape and length of the fingers and knuckles are measured.

Based on the data used to identify people, hand shape reading technology can be divided into the following three categories: palm application, hand blood vessel patterns, and finger geometry analysis. Mapping the different features of a hand is fairly simple and does not result in a large data set. However, even with a significant number of records, palm geometry does not necessarily distinguish people because the characteristics of the hands are so similar. Palm geometry does not achieve the highest degree of accuracy compared to other biometric methods. As the database continues to grow, it will be necessary to increase the number of distinctive features of hands to clearly identify and compare people with templates.

(3) Eyes

Biometric technology that analyzes the complex and unique characteristics of the eyes mainly includes iris recognition technology, retina recognition technology and cornea recognition technology.

The iris is a layer of colored cells surrounding the pupil. Each iris contains a unique structure based on features like crowns, crystals, filaments, spots, structures, pits, rays, wrinkles and stripes. The iris scanning security system consists of a fully automated camera that searches for your eyes and focuses when it finds an iris. After capturing an iris sample, software compares the data to a stored template. Trying to trick the system by blinking your eyes won't work.

Iris recognition is easier for users to use; it is more reliable, and there is no need for physical contact between the user and the device; but the size of the device is large, and the camera used for focusing is expensive and can cause dark eyes. Extremely difficult to read and requires a better light source.

The retina is the layer of blood cells at the base of the eye. Retinal scanning uses low-density infrared light to capture the unique characteristics of the retina, thereby capturing the unique pattern of blood cells. Some consider the retina to be a more unique biological feature than the iris.

The signature system has been controlled in a certain way to accept variables. However, it cannot consistently measure the strength of signatures without reducing acceptance rates. Because the signing speed is not fast, we cannot use it conveniently on the Internet.

(7) DNA

The DNA in the human body is unique and permanent within the entire human range (except that twins may have the same structure of DNA). Therefore, except that the identification of individual twins may lose its intended function, this method is absolutely authoritative and accurate. DNA identification methods mainly conduct identity identification based on the characteristics of the structure of DNA molecules in human cells that vary from person to person. The accuracy of this method is better than any other identification method, and it also has better anti-counterfeiting properties. However, DNA acquisition and identification methods (DNA identification must be carried out in a certain chemical environment) limit the real-time nature of DNA identification technology; in addition, some special diseases may change the structural composition of human DNA, and the system cannot correctly detect such types of diseases. crowd identification.

(8) Others

In addition to the several biometric technologies introduced above, others are currently being developed and researched through veins, ear shape, key rhythm, body odor, and walking. Recognition technology for gait, etc.