The numerous one is used in the biological recognition technology that the identity verifies, the recognition technology of fingerprint is most convenient at present, reliable, encroach on and the solution of cheap price. Characteristic on fingerprint human body it is unique,it have sex, uniquenesses personal, can’t duplicating, privacies absolute, and their complexity is enough to offer enough characteristic used for distinguishing; If we want to increase dependability, we only need to register more fingerprint, distinguish more fingers. The fingerprint module performance loving Deere to develop is remarkable, it is very fast to scan the tempo of fingerprint, it is very convenient to use; While reading fingerprint, users only need to gather the living subject finger with fingerprint the head keep in touch each other, it is to read the most reliable method of biological characteristic of the human body to gather the head and contact with fingerprint directly.

Second, entrance guard’s tool to lock

In daily life, people are ubiquitous must use the tools to lock of various entrance guards. Come to say, mainly have key, password, magnetic stripe card and IC card from the control method of entrance guard’s tool to lock.

With the improvement of people’s living standard, this indispensable essential apparatus of entrance guard’s tool to lock has brought a lot of troubles to life too. Everybody throws the key ‘  Or forget)  Experience,it want every day for reminding oneself to put well the key requiring mental skill, one clusters of keys heavy pieces of painful thing undoubtedly for thinking of the light person

And according to control method of the existing entrance guard’s tool to lock at present, there are certain potential safety hazards, the key, password and magnetic stripe card are easy to duplicate, steal; The security of the IC card is relatively high, but easy to lose. So, the tool to lock of entrance guard in the minds of people must have convenient, safe, esthetic characteristics now.

Third, entrance guard’s systematic summary of fingerprint

Entrance guard’s system refers to installing the electronic automatic recognition system of the intelligent card in the entrances and exits in the building because of the modern electron and information technology, through hold non- contact-type card come people correctly ‘  Or the thing)  Business turn over implement release, refuse, record,etc. operate intelligent administrative system, control for the entrance guard of the gate, the attendance management, system of intellectual building, high security entrances and exits management, safe and convenient discrepancy of securities trading management are controlled, purpose its for effective control personnel ‘  Articles)  Discrepancy,and details it record it is that all pass in and out,it last safety management against entrances and exits.

Register the fingerprint of personnel with this passway of discrepancy of authority in entrance guard’s system, only fingerprint proves that passes into, can enter, control the discrepancy of the confidential departments strictly, guarantee the security of goods and materials and property. Assign user’s fingerprint data in the corresponding entrance guard machine in the software of controlling of the entrance guard of the backstage supporter, can also upload the entrance guard to record in real time, produce entrance guard’s report form, offer basis on which the accident is traced.

Fourth, entrance guard’s systematic framework of fingerprint

According to key product, entrance guard’s system of fingerprint is loved Deere’s fingerprint to deal with module, user’s already existing control module, opening device and power system,etc. to make up.

4.1 systems make up

4.2 Liking dealing with the module in Deere’s fingerprint prove

Love Deere for made up of high performance digital signal processor DSP, large capacity FLASH and 300,000 picture element colored CMOSing fingerprint module. Concrete principle dealt with and discerned that the terminal products manufacturers of fingerprint do not need to understand fingerprint, only need to use and loving the fingerprint module of Deere directly, after MCU sends the order through interface of communication, the module of fingerprint can be finished corresponding fingerprint is input, fingerprint is dealt with, mean and spin proving and fingerprint than to the function.

System, entrance guard of fingerprint, change entrance guard systematic password or verification way of IC card originally into fingerprint of fashion prove way nowadays only. Let users not change any function of its product to improve its performance in of low input cases, have improved the cost performance of the products greatly.

4.2.1 Gather the head in fingerprint

Gather the total reflection principle that the head utilizes the miniature prism in fingerprint, the light source is reflected from the prism on the optical transducer. As people’s finger is pressed on the glass surface, change the surface of the miniature prism because the spine of fingerprint and pressure of valley are different; Reflect the light to get from the miniature prism, reflect the oil that all quantity depends on pressing among spine and depth, skin and glass of the valley of glass surface fingerprint. Through the picture preconditioning, digitization, grey level are dealt with, the picture strengthens and forms the fingerprint picture.

The corresponding technical indicator of the transducer:

The surface is hard to plate the glass of membrane

300,000 picture element colored CMOS

Resolution ratio 500dpi of the transducer;

The surface of transducer resists shock power and resists the ability of destroying: 4H pencil can assault for 1000 times and does not damage continuously within the range of 20cm.

4.2.2 DSP board

Get on the location machine and deal with the communication of the module with easy Deere’s fingerprint on 4.2.3

Fifth, entrance guard’s systematic characteristic of fingerprint

5.1 security

The changing the sex of fingerprint has determined with the uniqueness fingerprint is that the most low-priced, most reliable identity at present discerns the way, so utilize fingerprint to open the door safer.

5.2 accuracy

So long as users press the finger and can open the door lightly in time, accurately.

5.3 high stability

The independence works continuously, stability is good.

5.4 flexibility

Support multi-users, many groups to make up and open;

5.5 scientific process is managed

Divide period management, let management be scientific;

5.6 briefs on

Do not close the door to remind; Lose the electricity and point out the function;

5.7 can set up the warning finger

If someone is compelled and opened the door, use the warning finger to call the police. So as to protect the collective and personal safety of life and property.

5.8 is controlled long-rangely

Let outside your thousand li, can also manage at any time.

5.9 systems adopt differentiated control: Administrator and user.

Establish administration authority in the administrator step by step. Users’ fingerprint concentrates on central authorities’ managing the host computer to gather, store and manage the host computer in the central authorities. Open authority according to user, reach corresponding entrance guard plane under the fingerprint user.

Sixth, entrance guard’s systematic expandability of fingerprint

Entrance guard person who control can person who take off work, may network and manage too. The entrance guard manages and divides differently into in order to network entrance guard’s system and can’t network entrance guard’s system according to communication way. Person who network intellectual entrance guard control system lock by computer, communication converter, media reader, controller, card, cable ‘  Or infrared to penetrating, three rollers are transferred to the floodgate)  Make up, can install TCP/IP agreement module additional and solve large-scale entrance guard’s systematic networking project according to customer’s demand.

One of the key technology of the fingerprint products is the fingerprint transducer. The main one at present of fingerprint transducer is divided into three kinds. Optical transducer, the transducer of the semiconductor, ultrasonic transducer.

The optical transducer is the most traditional fingerprint transducer, reflect the fingerprint picture on the photoelectric device through a piece of prism, get the picture through sampling. The characteristic of the optical transducer is that a formation of image is effectual, the shortcoming is relatively bad to the dry formation of image of fingerprint, it was epidermis fingerprint that was gathered, not able to bear spots, and more difficult miniaturization.

The transducer of the semiconductor is divided for the electric capacity type again according to measuring the difference of principles, the inductance type, temperature sensing type three big classes. Three picture that technology gather these has his strong points, advantage with low costs generally speaking, small, the shortcoming is that the quality of the transducer formation of image is worse than the optical one, and antielectrostatic, it is bad to resist the destructiveness, the life-span is relatively short too. Divided into two big classes, pressing type and slipping type again according to user’s occupation mode.

Principle that ultrasonic transducer exceed to based on skin, reflect to whom supersonic wave produce with impedance measure fingerprint with air the fingerprint. This kind of technology had the characteristics that the formation of image is clear, it was genuine leather fingerprint that was gathered, the ability to resist spot is strong. But its shortcoming is that the price is very expensive, it is unable to be used on a large scale all the time.

The technology of the transducer has been already ripe day by day at present, towards higher quality of formation of image in the future, smaller volume of using, the more low-cost direction is developed. Among them develop fastest with the fingerprint transducer of the semiconductor, need bigger silicon to accumulate one-sidedly because of adopting and pressing the way semiconductor transducer of formation of image, so the space that the cost in the future reduces is limited. We think and mainly concentrate transducer development in future on the slipping type fingerprint transducer of the semiconductor, the products with typical in this respect have AES2501 series of Authentec Company,etc.. And the volume of the transducer that the main developing direction of optical transducer should dwindle mainly, improve the quality of the formation of image. The typical products have U.are.U 4000 series of DigitalPerson Company of U.S.A.,etc..

According to characteristic of the transducer, the transducer of the semiconductor is relatively suitable for pressing less number of times, the occasion with better environment for use such as information safety of the computer, hand-held device (PDA, cellular telephone)  ,The fingerprint U plate, fingerprint keyboard, the fingerprint mouse,etc.. The optical transducer is relatively suitable for fingerprint to lock, the entrance guard, attendance,etc. employ the occasion. Especially make fingerprint locked, what basically use is all the products of the optical transducer at present.

The fingerprint recognition algorithm is another key technology of the fingerprint products. The fingerprint recognition algorithm through using on PC at present has been already riper, but the algorithm used in various embedded systems has larger development space. Because of in the embedded system, treatment resource and memory resource that can be used are all very limited, so when the fingerprint algorithm is transplanted to the embedded system, must trade off in discerning performance and use cost, so the development of the embedded fingerprint recognition algorithm becomes one of the difficult points of product development of fingerprint. The ones that met for using are such as deformation, cast off a skin, rupture, questions such as the scar,etc., question needing overcoming in the fingerprint recognition algorithm.

At present but the embedded fingerprint algorithm is generally developed on DSP platform or ARM platform. The system developed on DSP platform, algorithm performance is stronger, discern the pace is very fast, but the difficulty of development of the algorithm is large, the manufacturing cost is higher. And it is lower to develop the difficulty in system based on ARM, but come up wholly and see discerning pace and result want difference a little, adapt to some application occasions of lower end. See it is still a position of occupying the mainstream of embedded fingerprint recognition algorithm based on DSP platform in the whole market at present.

Information such as the line of the human fingerprint of main foundation of fingerprint recognition, detail characteristic or appraised the identity to operation by the operator, benefit from the integrated manufacturing technology of modern electron and fast and reliable algorithm and study, begin daily life to enter into us already, become living beings measure learn, studying and deepening most at present, it is most extensive to employ, develop the ripest technology.

Fingerprint recognition algorithm

With dealing with the difference artificially, the general biological recognition technology company does not store the picture of fingerprint directly, but use different digitized algorithms to find and combine on the fingerprint picture than the characteristic to fingerprint. Each fingerprint have several unique, characteristic that can measure order, each characteristic have about 5 characteristics to order, ten fingers of ours produce the characteristic that 4900 pieces of independence can be measured at least, this is enough to state fingerprint recognition to be a more reliable differentiation way.

Discern fingerprint is mainly launched from two respects: Population characteristic and some characteristic.

Population characteristic

The population characteristic refers to those with characteristic that human eye can be observed directly. Including the line shape, mode district, some of core, some of trigonometry and line count etc..

Line shape: The fingerprint expert generally divides fingerprint into three big classes according to the trend of the line of spine and distribution situation on the basis of practising for a long time – -Ring type (loop, is also called the shape of fighting) , bow-shaped (arch) , the volution (whorl) .

Mode district: I.e. including population characteristic area at the fingerprint, area can say fingerprint which type does it belong to from then on. Some fingerprint recognition algorithms only use the data of district of the mode, some use the intact fingerprint made.

The core is clicked: Lie in fingerprint line advance gradually in the centre, it is reading fingerprint and as consulting ordering at being than to fingerprint. A lot of algorithms are based on the core and clicked, can only deal with and discern that has cores fingerprint lighted.

The trigonometry is clicked: Lie in first branching since the core is clicked order or not broken a bit, either two stripe way assemble place, isolate a bit, roll over, transfer place to, or it is a bit stranger to point to these. Some trigonometries are offered the place that count beginning that is followed of a line of fingerprint.

The line is counted: I.e. the quantity of the line of fingerprint in district of mode. While calculating the line of fingerprint, generally connect key some and trigonometry to click first, the quantity of this line and fingerprint with crossing line can think it is a line of the fingerprint that is counted.

Some characteristic

Some characteristic refers to the nodal characteristic on fingerprint, these nodes with a certain characteristic are called the detail characteristics or characteristic to click. Two pieces of fingerprint will often have the same population characteristics, but their detail characteristic, but can not be all the same. The line of fingerprint is not continuous, smooth and straight, but often present cutting off, branching or transferring. These break some, some of branching and turning point on calling ” The characteristic is clicked ” ,Some of the characteristics are offered the affirmation information of only fingerprint, among them the most typical one terminates some to click with branching, include difference order, isolate some, ring ordering, short line,etc. still while being other. The parameter that the characteristic is lighted includes: Direction ( The node can be in certain direction) , camber ( Describe the line side to pace changing) , the position (describe by x/y coordinate in the nodal position, can be absolute, can click some of trigonometry or characteristic too) .

Gather the technology of the fingerprint picture

It is a very complicated problem to obtain the good fingerprint picture. Because fingerprint measured to use for quite young one epidermis only, so fingerprint gather apparatus should have fine resolution ratio enough in order to detail to win fingerprint. Fingerprint pictures used gather the apparatus at present, basically on the basis of three kinds of technological foundations: Optical technology, semiconductor silicon technology, ultrasonic technology.

Optical technology

It is the most remote, most popular technology of history to gather fingerprint through optical technology. Put the finger on the optical lens, the finger throws it in the coupling device of electric charge (CCD) with the prism under the circumstances that the built-in light source shines Go, and then form the line of spine (the line of line with certain width and trend in fingerprint picture) Black, valley line ( Sunken part between the lines of line) White digitization, many grey levels fingerprint picture that can be dealt with by the apparatus algorithm of fingerprint.

Gathering the apparatus in optical fingerprint has obvious advantages: It has already passed more long-time application to test, has met the variation of temperature to a certain extent, cheap, can achieve 500DPI high-resolution wait relatively comparatively. The shortcoming is: Because of requiring enough long optical distance, require the enough large size, and the too dry and too greasy finger will make the result of the optical fingerprint products bad.

Silicon technology (CMOS technology)

On later stage of 1990s, the technology based on effect of electric capacity of semiconductor silicon became more and more ripe. The silicon transducer becomes a polar plate of the electric capacity, the finger is another polar plate, it is bad to utilize spine and valley which point the line of line to the electric capacity between the smooth silicon transducers, form the grey level picture of 8bit.

The technological advantage of silicon can obtain picture quality better than optical technology on smaller surface, obtains resolution ratio (lower surface of Line 20000 decline causing the cost on the surface of 1cm * 1.5cm too and can be integrated in smaller apparatus) . The shortcoming is easy to be interfered with, the relative difference of dependability.

Ultrasonic technology

In order to overcome the optical technical equipment and deficiency of the silicon technical equipment, gather the apparatus to already present in a new kind of ultrasonic fingerprint. Its principle is to utilize supersonic wave to have ability to penetrate material, and is up to the return waves echo (on supersonic wave reaches surface of different materials of different production of the material of different size, it is different from intensity reflected that absorbed, penetrated) ,So utilize skin and air to acoustic difference of impedance, can distinguish fingerprint spine and position that valley locate.

The ultrasonic frequency that ultrasonic technology uses exceeds 1* 109Hz for 1* 104Hz, it is (the same as intensity of medical diagnosis) that energy is controlled the intensity that can’t harm to the human body . The technological products of supersonic wave can reach the best precision, it requires the clean intensity of finger and level relatively low, but it will be longer than two kinds of aforesaid products to gather time obviously.

The characteristic is picked up, proved and distinguished

After a high-quality picture is picked up, need a lot of steps to transform its characteristic into a template compounding, this course, known as the characteristic to pick up the course, it is a core of pointing scanning. After a high-quality picture is picked up, it must be changed into a useful form. If the picture is a grey level picture, relatively shallower part will be deleted, and relatively deeper part has been turned into deceiving. Picture of spine have 5 contract detailed to get one picture element, can accurate to orient spine to be a bit more disconnectedly diverging in this way. The picture of the small detail comes from this picture dealt with. In this regard, even very meticulous picture have details out of shape and wrong details, these out of shape straining by wrong detail except that.

Except that localization and contained angle application of method of detail, can also divide the detail through type and quality of detail. The advantage of this method lies in the pace searched has greater improvement, one a prominent one, particular detail, it getting only and easy to make it succeed in not to match. Method which some manufacturers adopt is that the mode match the method, handle the fingerprint picture through inferring the data of a group of particular spines.

In respect to employing the method, the recognition technology of fingerprint can be divided into proving and distinguished.

Verification carries on than the course of the identity to confirming more one-to-one through fingerprint and a fingerprint that has already registered of gathering one live. Fingerprint is stored with certain compression form, and with their names or its identification(ID, PIN) Connected. Comparing with the scene subsequently, verify its identification first, then utilize systematic fingerprint to compared with fingerprint gathered live prove its identification is legal in coming. Prove that has actually answered such a question: ” Is he this person that he calls oneself? ” This employs the method that is used in the system more.

It is to compare the fingerprint in fingerprint and fingerprint database gathered to distinguish live with one by one, find out the fingerprint of matching on-the-spot fingerprint from it. This lets too ” More than one pair of match ” . It is to answer such a question to distinguish: ” Who is he? ”

Fingerprint is human body’s unique characteristic, its complexity is enough to offer the characteristic used for distinguishing. It is gradual and ripe with supporting technology relevantly, the recognition technology of fingerprint has already become most convenient at present, reliable, not encroaching on and biological recognition technology solution of cheap price through the development for many years, there is very great development potentiality in the application of markets.

The recognition technology of fingerprint mainly involves four functions: Read fingerprint picture, draw characteristic, keep data and than right. At the beginning of, read the picture that the apparatus read to human fingerprint through fingerprint, fetch after the fingerprint picture, should carry on preliminary treatment to the primitive picture, make it clearer. And then, it is expressed that fingerprint distinguishes the figure set up fingerprint of the software – -Characteristic data, kinds of folk prescription to conversion,can from changing fingerprint but characteristic data can last fingerprint from characteristic data, two pieces of different fingerprint will not produce the same characteristic data. Some algorithms make the node and direction information up to produce more data, information of these directions shows the relation between each node, still deal with the whole fingerprint picture in some algorithms. In a word, these data, are usually called the template, keep it for 1K size record. No matter how they make up, still the standard of no template so far, the abstract algorithm of no announcement too, but each manufacturer goes one’s own way. Finally, through the fuzzy method to compare of the computer, compare the template of two pieces of fingerprint, calculate their similar intensity, get the match results of two pieces of fingerprint finally.

Our palm and protruding concave indignant line that produce of skin on the finger, foot, surface of toe inboard will form various pattern. The existence of these lines has increased the frictional force on the surface of skin, enable us to pick up the heavy object with hand. People notice too, the line of the skin including fingerprint is in the pattern, break some and intersect to to have nothing in common with each other, that is to say, it is the only one. Depend on the uniqueness, we can getting corresponding man and his fingerprint, compare through the fingerprint that is kept to his fingerprint and in advance, can verify his true identity. This kind of technology of relying on body characteristic of the human body to verify the identity is called biological recognition technology, fingerprint recognition is one kind of the biological recognition technology. At present, from the practical viewpoint, the recognition technology of fingerprint is the identity differentiation method which is superior to other biological recognition technology. This is because the characteristic that fingerprint had nothing in common with each other, not basically changed all one’s life has already been generally acknowledged, have laid the good technological foundation for security personnel’s fingerprint automation recognition by research and practice of the automatic recognition system of fingerprint in the warnings of nearly twenty or thirty years. Especially the reliable, stage of moderate price that easy to operate, accurate that the existing fingerprint automatic recognition system has already reached, it is the practical living beings that determine the method.

Fingerprint refers to the protruding concave not smooth line that produces on the skin of terminal front of finger. The existence of these lines has increased the frictional force on the surface of skin, enable us to pick up the heavy object with hand. Though fingerprint is only a small part of the human skin, however, it contains a large amount of information. Line of skin the in pattern, break some and intersect be had nothing in common with each other, call them in information processing ” The characteristic ” ,Each finger of these characteristics is different. Depend on characteristic getting only, we can getting corresponding man and his fingerprint, through comparing his fingerprint characteristic and fingerprint characteristic kept in advance, can verify his true identity.

The automatic recognition system of fingerprint passes special photoelectric conversion equipment and computer picture treatment technology, gather, analyze to the fingerprint of living subject and than correctly, can distinguish the personal identity automatically, fast, accurate. What the system generally mainly includes to fingerprint picture gathering, fingerprint pattern process, characteristic drawing, characteristic value, than to with the course of matching etc.. The integrated manufacturing technology of modern electron makes the fingerprint picture read and deal with the apparatus to miniaturize, the operation pace of personal computer developed at full speed at the same time has offered and can carry on fingerprint on the computer even one-chip computer than the possibility to operation, and outstanding fingerprint is dealt with and guarantee to discern the accuracy of the result than to the algorithm.

In the computer system, fingerprint recognition can be used for starting the machine the log-in identity is confirmed, the visit authority of the long-range network data base and affirmation of identity, bank savings defend the encryption method that falsely claim as one’s own and deposit and withdraw at any branch bank, the insured’s identity is confirmed in insurance trade, the identity of the securities withdrawer of the futures is confirmed, the identity of treating the insurer of systematic Chinese medicine of health care is confirmed etc.. Record, at special card of use, pass fingerprint information scene than right, can prevent the fraud of pretending to be etc.. For example: Credit card, medical card, meeting card, deposit card, driving license, admission card for entrance examination, passport anti-counterfeit,etc..

The automatic recognition technology of the computer fingerprint is entering into our actual life from the science fiction and Hollywood film, perhaps one day, you needn’t hand-carry that bunch of keys, only need the finger to press, the door will be opened; Needn’t remember annoying password that either, can utilize fingerprint withdraw deposit, computer log-in. Believe for this day, will not be too far.

Because the position where the right-falling stroke tallies is not totally the same each time, impetuses are different will bring the deformation in various degree, a large amount of fuzzy fingerprint exists again, how to draw the characteristic and realize correctly that matches correctly, it is a key to the recognition technology of the fingerprint. Fingerprint recognition technology involve pattern process, pattern-recognition, machine study, computer vision, mathematics morphology, light wave person who analyze numerous disciplines.

The recognition system of fingerprint is a typical mode recognition system, including the fingerprint picture is obtained, dealt with, the characteristic is drawn and than the reciprocal module.

The fingerprint picture is obtained: Gather the appearance and can gather the fingerprint picture of the living subject through special fingerprint. At present, gather the appearance mainly having a living subject optics type, electric capacity type and press the sense type in fingerprint. As to the thing that technical indicators such as resolution ratio and area of gathering,etc., the trades of public security men have already formed the international and domestic standard, but the others still lack and seek unity of standard. Can be divided into and pressed down and printed fingerprint and level to press down the fingerprint of printing rollingly on the whole according to gathering the fingerprint area, the trades of public security men generally adopt and press down the fingerprint of printing rollingly. In addition, can obtain the fingerprint picture through the scanner, digital camera,etc. too.

The fingerprint picture is compressed: The fingerprint database of the large capacity must be stored after compressing, in order to reduce the memory space. The main method includes JPEG, WSQ, EZW,etc..

The pattern process of fingerprint: Fingerprint regional detection, picture quality judge, direction picture and frequency estimate, picture strengthen, fingerprint picture two value and thinning.

Fingerprint classification: The line type is the basic classification of the fingerprint, divided according to pattern and triangular basic shape of centre. The shape subordinated toing type of the line, name with the form of the centre line. Ten fingerprint analytic approaches in our country divide fingerprint into three major types, nine kinds of shapes. General, the automatic recognition system of fingerprint divides fingerprint into the bow-shaped line (arcual line, account shape line) , dustpan appear line ‘ Left dustpan, right dustpan) , fight shape line and miscellaneous shape line,etc..

Fingerprint shape and detail characteristic are drawn: Fingerprint shape characteristic include in the center ‘ Have, leave) Until trigonometry a bit ‘ Left deviation, right) Wait, detail of fingerprint characteristic order, include line starting point, terminal point of line, combine some mainly and branching order.

Fingerprint is to right: Can follow the line shape of fingerprint to match thickly, and then utilize the fingerprint shape and detail characteristic to match accurately, provide the similar scores of two pieces of fingerprint. On the basis of the ones that employed, arrange in an order or provide the judgement result that is the same fingerprint to the similar score of fingerprint.

In the present computer employs, include a lot of very secret file protect, mostly use ” User ID + password ” Method it comes to be to carry on user identity authentication and visit it control. However, if once the password is forgotten, or is stolen by others, the security questions of computer system and file have been threatened.

With the progress of science and technology, the recognition technology of fingerprint has already begun to enter in PC World slowly. A lot of companies and research institutions have all made very great breakthrough progress in the field of recognition technology of fingerprint at present, put out a lot of fingerprint recognition and perfect application products that combined of traditional IT technology, these products have already been approved of by more and more users. Commercial field in which the recognition technology of fingerprint is used for having high expectations for security more, move, work field Fujitsu, Samsung, IBM to have much achievement international famous brand have technology and applicant comparatively ripe fingerprint recognition system in commercial affair, carry on the simple introduction to the application of fingerprint in the notebook computer of recognition system below.

As everyone knows, the identity when the note-books of some brands adopted the recognition technology of fingerprint to be used in user’s log-in two years ago is appraised, however, the fingerprint system put out at that time is an optical recognition system, according to the present statement, it should be the recognition technology of the 1st generation of fingerprint. Optical fingerprint recognition system can penetrate the top layer of skin because of the light ‘ Fatal character skin layer) ,So can only scan the surface which points the skin, or scan the fatal character skin layer, but can’t deepen the genuine leather layer.

In this case, the clean intensity with superficial finger, influence the result discerned directly. If, users glue more dusts on the finger, perhaps will discern the situation making mistakes. And, if people make a fingerprint hand mould, may pass the recognition system according to the finger, as to user, it is not very safe and steady that use.

So the second generation of electric capacity type transducer appears, the transducer technology of electric capacity is to adopt permutation and transducer electric board which replaces the order, the form of replacing the board is two electric capacities board, and mountain valley and ridge of fingerprint become non-conductor between the boards. The transducer that the constant between the two is dielectric measures and changes in next life and becomes the fingerprint picture. But because transducer surface use silicon to be material apt to damage, lead to the fact service life reduce, and it and ridge unsmooth to come to form fingerprint picture so difficult finger discerning rate low to dirty finger wet finger,etc. through mountain valley of fingerprint.

Develop until today, the fingerprint recognition technology of the third generation of biological radio frequency appears, the transducer technology of radio frequency is to transmit the micro- radio frequency signal out through transducer, which penetrates the finger epidermis layer detects the line of the inner layer, to obtain the best fingerprint picture. Do finger correctly, Chinese finger, do finger difficult finger through can be up to99@%, Anti-counterfeit fingerprint ability is strong, the discernment principle of the sensitive device of fingerprint only reacts to skin of people’s genuine leather, having stopped the question of artificial fingerprint fundamentally, the wide warm district: Suitable for very cold or very scorching area. Because the radio frequency transducer produces the high-quality picture, the technology of radio frequency is the most reliable, have a solution most effectively. In addition, the high-quality picture also allows to reduce the transducer, does not need to sacrifice the dependability of authentication, lower costs and make radio frequency transducer thought apply to, can move, receive constrained field any with size.