Comparison of advantages and disadvantages between capacitive and optical fingerprint scanner
In the end, optical or capacitive fingerprint scanner recognition technology is good:
A. Optical fingerprint acquisition technology is the oldest and currently the most widely used fingerprint acquisition technology. Optical fingerprint collection equipment began in 1971. When the light is irradiated to the valley through the glass, the glass is totally reflected at the interface between the glass and the air surface. The fiber is reflected to the CCD, and the light that is directed to the ridge does not emit completely, but is absorbed or diffusely reflected by the contact surface of the ridge and the glass. Going somewhere else, a clear fingerprint image is formed on the CCD.
Optical acquisition equipment has many advantages: it has experienced the test of long-term practical application, can withstand a certain degree of temperature change, has good stability, and can provide images with a resolution of more than 500 DPI, and the sensitivity of fingerprint recognition is very high, without 1 Secondly, in addition to the fingerprint collector, the tempered glass is generally used, which can protect the fingerprint collector very well to a certain extent, and the service life is very long. The temperature range of fingerprint awareness is between minus 20 degrees and 85 degrees. In view of this many characteristics, it has gradually become the mainstream fingerprint collection technology on the market.
The principle of capacitive fingerprint scanner is: This type of sensor, whether capacitive or inductive, has a similar principle. On a "plate" with thousands of capacitive fingerprint scanner integrated, the finger is attached to it and it forms a capacitor. On the other side of the (inductance), since the finger plane is uneven, the actual distance between the bump and the concave contact plate is different, and the capacitance/inductance value formed is different. The device does not use the collected principle according to this principle. The summary of the values completes the fingerprint collection.
It consists of a capacitor array with approximately 10,000 miniaturized capacitors inside. When the user places his finger on the front side, the skin forms a plate of the capacitor array. The back of the capacitor array is the insulating plate. Since the distance between the ridges and valleys of the fingerprints of different regions is not desired, the capacitance of each unit is changed accordingly, whereby a fingerprint image can be obtained.
Capacitive fingerprint sensors have the advantages of small size and high recognition rate. These unique advantages have attracted Sony, and other well-known companies, and developed unique products. Of course, as a fingerprint sensor with great potential and representing the future development direction, there are certain limitations, which are characterized by being susceptible to static electricity. In severe cases, the sensor may not collect images or even be damaged by itself; finger sweat salt or other dirt Objects, as well as finger wear, can cause image acquisition difficulties, surface scratch resistance is poor, wear resistance is not as good as glass, large area manufacturing cost is high, so the image capture area is small; sensor stability, especially times Further verification of the optimal performance and other aspects. However, the capacitive fingerprint sensor recognizes that the dry finger in winter is better than the optical one. With the improvement of the technology and the cooperation of the auxiliary functions, the author believes that the future application of the capacitive fingerprint sensor will be wider.
The disadvantage of optical fingerprinting is that the volume is larger than that of the capacitive fingerprint scanner, and the dry finger recognition is degraded in winter. However, in view of the above advantages, the optical fingerprint collecting instrument is now widely used in fingerprint door locks, fingerprint access control, fingerprint punching machines, and management of automobile fingerprint anti-theft devices, and is used in many countries. Currently, two fingerprint identification technologies have their own advantages.
Huifan's patented product was the world's first fingerprint reader with a Bluetooth-readable IC card with waterproof function. After 15 years of mass production, it replaced the HF4000 as the second phase of Pakistan Telecom's engineering products, and was also the presidential election product of Angola.
7000 babies have participated in many projects, such as Nigerian presidential election, TTCL project, Pakistan government attendance, farm worker member management, taxi project, baby vaccine registration toe and many other successful projects, which is the darling of Huifan.
HF7000 NFC Bluetooth Fingerprint Scanner of Nigerian Presidential Election
HF7000 Capacitive Fingerprint Scanner of Farm Worker Member Management
HF7000 Free SDK Fingerprint Scanner of Pakistan Government Attendance
HF7000 Programable Fingerprint Scanner of Taxi Project
HF7000 High Quality Fingerprint Scanner of Baby Vaccine Registration Toe
HF4000 is USB fingerprint scanner with optical sensor. It meet ISO19794-2/ANSI378 international standard, supports Android, Windows, Linux operating systems. It is widely used for registration & verification for different industries, like telecom, bank, e-heath, logistic, employee attendance etc.