From the early mechanical locks, to the modern electronic locks and smart locks, to the development of the new smart locks represented by fingerprint recognition in recent years, fingerprint locks, the development of science and technology and its industrial penetration have also triggered locks. The revolution of the industry brings users a wonderful experience and enjoyment of high quality of life, work, and entertainment from the aspects of safety, convenience, and management.

Fingerprint lock requirements

As a third-generation security product, the fingerprint lock breaks the function of the mechanical lock single opening in the traditional sense. It is a high-tech product integrating optical, mechanical, electronic and fingerprint core algorithm technology. Today's fingerprint locks have many functions, such as networking, door-opening, remote control, smart alarm, multiplayer mode, administrator level, and more. These are closely linked to the IT industry's electronic information technology. Then with the strengthening of people's security awareness, the improvement of living standards and needs, new functions and new demands are constantly emerging. At the same time, they are also subject to the requirements of the national government agencies.

In addition, for the linkage system of the banking system, the three-door linkage door of the treasury, the fingerprint gun cabinet, the tax system, the prison, the medical and health, the education system, the examination system, etc. all have special needs.

Fingerprint lock core technology analysis

As a high-tech electronic information product, fingerprint lock is the focus of development for the following core technologies:

1. Fingerprint recognition algorithm: At present, the identification algorithm of our company's fingerprint products is the core algorithm of our company's own intellectual property rights. The corresponding technical indicators have reached the world's leading position, among which: the false recognition rate (mistaken) Rate): <0.0001%: one in a million, which is the probability of accidentally unlocking; the rejection rate: <0.3%: three thousandths, that is, the probability of refusing to unlock after storing the fingerprint; rotation angle: positive and negative 180 degrees, that is, 360 degrees of arbitrary rotation; maximum translation: 5mm; recognition time: <0.2s, the time of fingerprint comparison processing.

2. Optical acquisition instrument: Among the many fingerprint acquisition sensors, the optical acquisition system is the most reliable, adaptable to various occasions, resistant to damage and long life. And now there are two products (light, dark background), fingerprint lock products that have been applied after strict testing.

The acquisition device has the following key specifications: resolution (number of pixels): refers to the number of pixels per inch (dpi). The FBI and the Ministry of Public Security's standards require that the police and some commercial equipment should not be less than 500dpi; if it is less than this value, the adjacent fingerprint lines can no longer be clearly distinguished on the image, resulting in the feature extraction algorithm unable to locate the feature points. Area Size: The size of the rectangular area where the fingerprint image is effectively obtained. Larger area size can obtain larger fingerprint images, providing more fingerprint ridge lines and valley lines, making clear identification and resolution easier. The current optical collection instrument size is: 18*22mm, which can guarantee 500dpi. (actually 508dpi); gray level: the number of bits per pixel gray value in the image, that is, A/D conversion accuracy, FBI standard requires 8 bits, but our product is 256 levels of gray, so as to ensure acquisition The lines can be clearly reflected. Geometric Accuracy: The geometric distortion of the image of the acquisition device, expressed as a relative percentage, which we call professionally known as geometric accuracy or distortion. In most optical collector systems, this problem can occur. For example, systems using prisms have trapezoidal distortion, rectangular distortion, etc., but can be corrected by optical system compensation. If the calibration is not compensated, it will cause different positions on the surface of the collector. Inconsistent deformation of the fingerprint image, which affects the identification of the fingerprint; if the image needs to be uploaded to the computer system, the image will be distorted. If the distortion parameter cannot be controlled during production, the fingerprint lock cannot be locked in the network identification system. Identifying images captured by other locks makes the networked fingerprint recognition system impossible.

Comprehensive theory of fingerprint recognition

Fingerprint recognition technology is a kind of biometric technology; it is well known that biometric technology is a solution that relies on the physical characteristics of the human body for identity verification. The biological characteristics of the human body include fingerprints, faces, sounds, irises, corneas, palm prints, skeletons, veins, etc. Behavioral characteristics include signatures, sounds, button strengths, exercise postures, etc., including forensic medicine, blood, DNA, etc. belong to the body. Characteristics. The core of so-called biometric identification is how to acquire these biometrics and convert them into digital information, which is stored in memory. The microprocessor uses a reliable matching algorithm to complete the process of verifying and identifying personal identity.

Since the human body features the inherent non-replicable uniqueness of the human body, this biometric key cannot be copied, stolen or forgotten. Common passwords, IC cards, stripe codes, magnetic cards or keys have many disadvantages such as loss, forgetting, copying and theft. So with the biological "key", you don't have to carry a bunch of keys, and you don't have to bother to remember or change your password. System administrators don't have to worry about forgetting their passwords.

Humans have experienced three stages of development in the effectiveness and convenience of pursuing the security of documents, transactions and articles. The first stage, the initial method, is to use a variety of mechanical keys that are already familiar to everyone. The second phase is the development of mechanical keys to digital keys such as passwords, barcodes, IC cards, IB cards, RF cards, remote controls, and more. The third stage is to use the biological characteristics inherent in the human body to identify and verify identity. Biometrics is the highest level of security keying in today's digital life.

Among the current biometrics, fingerprint recognition is the easiest to develop and the most mature biometric technology. It is also the most widely used. Fingerprints are very compatible with biometric systems in terms of relativity and stability. According to statistics from the International Biometrics Group IBG, fingerprint recognition occupies the protagonist of the biometrics market. It accounts for 80% of the biometric market.