Everyone's fingerprints are unique. Now that the technology is developing, fingerprints have become another ID card for people!
There are three types of human fingerprints: "bucket shape", "skip shape", "bow shape"!
The distribution of this shape has a lot to do with the region. For example, in the fingerprints of Chinese and Japanese, the occurrence rate of bucket pattern and skip pattern is roughly the same, accounting for more than 90% of the total; in European fingerprints, The appearance rate of skip-shaped patterns is relatively high; in American fingerprints, the appearance rate of bow-shaped patterns is relatively high.
Our common "optical fingerprint identification system" uses light reflection imaging to identify fingerprints.
This type of fingerprint module has certain requirements on the temperature and humidity of the environment in which it is used. If you ride a bicycle in the winter, you will often not be able to check in when you run to the door, and you must put your cold finger to your mouth to breathe. It will be recognized in a while, not to mention embarrassing.
Fingerprint recognition button on mobile phone
The small button on the mobile phone is actually a capacitive fingerprint module. It uses the silicon wafer and the conductive subcutaneous electrolytic solution to form an electric field. The fluctuation of the fingerprint will cause different changes in the pressure difference between the two. Realize accurate fingerprint measurement.
This method has strong adaptability and no special requirements for the use environment. At the same time, the volume of the entire component is still relatively small, which makes the technology popular on the mobile phone side.
Fingerprint collector of public security system
When we go to apply for ID cards and reissue ID cards, we need to enter fingerprints. This entry device is a biometric radio frequency fingerprint identification system. The accuracy of this device is very high.
It emits a small amount of radio frequency signal through the sensor itself, and penetrates the skin of the finger to control and measure the lines of the inner layer to obtain the best fingerprint image.
The fingerprint sensor's identification principle only reacts to human dermal skin, which fundamentally eliminates the problem of artificial fingerprints. Wide temperature zone: suitable for particularly cold or extremely hot areas. Therefore, radio frequency technology is currently the most reliable and powerful solution.
Common ground
However, regardless of the collection method, the collected information is not a picture of the fingerprint, but a string of codes calculated by a special algorithm, which is like a corresponding barcode based on the fingerprint. If you reverse the comparison, You can calculate whether two fingerprints are from the same person. There are generally four steps.
1. Fingerprint collection. When fingerprints are collected for the first time, the same finger is often entered in all directions. This is to record the entire fingerprint completely, because fingerprint fragments cannot be used as identification evidence.
2. Fingerprint evaluation. Strictly judge the entire information, if it is unqualified, it needs to be re-collected.
3. Extract features. This step is a very critical step and requires powerful algorithm software to support it. The collected fingerprint endpoints, bifurcation points, divergence points, isolated points, loop points, short lines and other information are mathematically converted and stored in the database. middle.
4. Fingerprint matching. If the fingerprint identified again has the above information, the identity information can be determined and the operation can be performed.
At this time, we return to the previous topic to see if the fingerprint lock is safe or not. In general forensic science, it is necessary to determine whether two fingerprints are from the same person. The characteristics of fingerprint comparison need to be more than 30 to be judged. Our mobile phones do not calculate so accurately, but with the continuous update of the algorithm, the recognition of the mobile phone The level is also developing rapidly, and the safety is also a qualitative leap.
Will the fingerprint disappear? This is really possible. It is indeed found that very few drugs will temporarily blur or even disappear fingerprints. If you need to enter and exit at this time, you need to carry a certificate issued by a doctor with you.
If you want to completely destroy the fingerprints, it is not impossible. If the dermal layer of the fingers is damaged by various violent means, the fingerprints will indeed not grow back.