CN101548496A - Method and apparatus for biometric identification - Google Patents

Abstract

The invention describes the first practical, cost effective, truly non-contact implementation of a subcutaneous vein pattern biometric sensor. A laser diode (LD) illuminates the hand in such a way that the pattern of reflected radiation, when viewed by a conventional vein pattern infrared imager, provides a direct measure of target range. Said target range measurement is used to create a visual or audio signal that instructs the individual being scanned to place the hand at precisely the optimum range, such that the vein pattern is in focus. Furthermore, a system and apparatus are described to direct the individual being scanned to move the hand to an optimal horizontal registration or position with respect to the infrared imager.

Description

The method and apparatus that is used for bio-identification

Technical field

The present invention relates to biometric identification of individuals by the part (most typical is the part of hand) of human body being carried out infrared imaging, using subcutaneous vein pattern to discern.

Background technology

The commercial market that increases rapidly though the biometric identification of individuals representative is little.According to estimates, the market to biology sensor in 2008 and system will reach 4,000,000,000 dollars.Increase to use the motivation of bio-identification to comprise any anti-terrorism examination (for example), add by the protection of stealing financial number of the account and the identity theft that password caused the control that enters at the examination of airline passengers and government facility and commercial facility place.About the latter, biological recognition system has been installed at their ATM place by some main banks.Each user is recorded in his or her biological characteristic on the data card, and before allowing to enter bank account, must be by the biometric scan of individuality be come in real time pattern to be mated.The term here " data card " is meant at can and repeatedly reading the universal description of the digital information storage medium (for example, magnetizing mediums, semiconductor memory, light medium etc.) of any kind of biological attribute data to its write-once.

Developed multiple technologies, comprised finger scan and retina scanning at biometric identification of individuals.One of the most promising biometric discrimination method is to use the infrared imaging of adversary's subcutaneous vein pattern.For example, No. the 2nd, 156,127, the British patent of submitting on March 19th, 1985 referring to Rice J. " Method Of And Apparatus For The Identification Of Individuals "; No. the 5th, 787,185, the United States Patent (USP) " Biometric Identification Of Individuals By Use OfSubcutaneous Vein Patterns " that Clayden submitted to and announces on July 28th, 1998 September 29 nineteen ninety-five; And " Palm Vein Authentication Technology And ItsApplications " (Proc.Biometric Consortium Conf. of Watanabe M., T.Endoh T., M.Shiohara and S.Sasaki, 19-21 day in September, 2005, Arlington, VA, USA).More in general, can carry out imaging to the subcutaneous vein pattern of the arbitrary portion of human body.Infrared sensor is caught the image of subcutaneous vein pattern, utilizes computer or microprocessor to come it is analyzed then, and itself and the image that is stored on the individual data card are compared, to determine that accepting still is this individuality of refusal.Compare with visible radiation, the near-infrared radiation transdermal and the hypodermic degree of depth are much bigger, the feasible more detailed image that can obtain subcutaneous vein pattern.Substituting of the data card of the biometric profile of storing as comprising can be stored in this profile on the computer network, only need import the personal identification number so that be scanned individuality.The advantage of vein pattern identification is, has shown that palm vein pattern and finger vena pattern are individual exclusive, the extremely difficult explanations of forging and be easy to relatively.Find that even the identical twin, the vein pattern of their palm and finger also is different.Opposite is shown that the caly model of fingerprint can be cheated fingerprint scanner, and the generation misconnection to be subjected to.

By the bio-identification of the imaging of hand vein pattern is that with respect to another advantage such as the alternative technique of finger scan in theory, the venae subcutaneae infrared thermoviewer can utilize the noncontacting proximity sensor of complete health to realize.Fingerprint scanner is the contact equipment that depends on high resolution capacitive (but not optical imaging sensor) in essence.In some culture, everyone transducer that must touch that enters communal facility is considered to extremely unwelcome.Biology scanner can not be discerned the people who has gloves on.In addition, everyone touch sensor that must touch that enters communal facility can gather dirt, causes the reduction of certainty of measurement.Some Asian countries has adopted biology sensor previously, uses them to control entering government buildings, commercial building and ATM (automatic teller machine); Following market comprises airport security etc.If the Asia suffers the large-scale outbreak of mortality bird flu or similar infectious disease, then may cause serious destruction to biological recognition system based on touch sensor.The ideal non-contact vein pattern biometric sensor only requires the user hand to be remained on vacantly the top of infrared thermoviewer.

The technological challenge of the maximum that is faced when attempting the contactless vein pattern biometric sensor of design is although in fact all this biological infrared thermoviewers have fixing focal length, target (hand) be focused on the infrared thermoviewer.Infrared thermoviewer has fixing focal length, mean, only in target when the distance (target zone) of imager equals the fixed value of appointment, this goal-focus is aimed at.As example, imagination attempts taking literal on this page target (page or leaf) being remained on remarkable this video camera that do not utilize simultaneously of fixed focal length target zone apart from the distance of fixed focal length video camera and this video camera.This will cause the image out of focus that write down, make to read part or all of literal on this page.For vein pattern biometric sensor, the image of out of focus will cause unrecognizable vein pattern, make all individualities that is scanned be refused by biological recognition system.By checking that the FujitsuPalmSecure specification is clear that the sensitivity of vein pattern imager to target zone, wherein, desired target zone is defined as 50 ± 10mm (PalmSecure palm vein Verification System, U.S. Fujitsu Computer Product Company).The optics of employed infrared thermoviewer module comprises in vein pattern biometric sensor: infrared LED luminaire, long pass infrared filter, universal focus lens system and CCD or CMOS detector array.These parts self can not provide the data that can accurately determine target zone according to it.Must add additional electrooptic block in the infrared thermoviewer module provides the data that can determine target zone according to it, thereby must add the device of proofreading and correct the out of focus situation in bio-sensor system.

Can attempt in vein pattern biometric sensor to add to most of digital camera system in the similar automatic focus lens of automatic focus lens that comprised; Yet this can produce a plurality of other problems: (a) the automatic focus lens combination of traditional cheapness is difficult in the desired very short target zone of bio-imaging instrument (about 50mm) and wide visual field place sharply focused image is provided; (b) the high-quality automatic focus lens that are suitable for biologic applications significantly increase the cost of transducer; And (c) mechanical part of cheap autofocus system can wear and tear along with the desired frequent use of typical biology sensor (for example, jede Woche uses several thousand times, annual 52 week).

Leading two Fujitsu of company and Hitachi recognize the importance of noncontact or non-tactile feature in the vein pattern biometric sensor field, accept because this relates to by customer base widely.By patent that Hitachi employee write and patent application (US20050185827, US6813010, US6912045, US6993160) and the importance of having emphasized the noncontact feature in by patent that Fujjitsu employee write and patent application (US20050148876).Yet, Fujitsu, Hitachi or their rival all fail to develop and the above-cited patent application of offering for sale described in type, real contactless vein pattern recognition sensor.

Hitachi SecureVein biology sensor carries out imaging to the subcutaneous vein pattern in the finger, and provides with several slightly different versions.Yet each release requirement user places the hand rest or the finger rest of his or her hand and moulding in contact, and the hand rest of moulding or finger rest are fixed target (finger) scope and horizontal registration with respect to infrared thermoviewer.

The Hitachi patent and the patent application of quoting previously comprise: No. the 2005/0185827th, the U.S. Patent Application Publication " Personal Identification System " that Kono, Umemura, Miyatake, Harada, Ito and Ueki submitted on April 13rd, 2005; No. the 6th, 912,045, United States Patent (USP) " PersonalIdentification System " that Kono, Umemura, Miyatake, Harada, Ito and Ueki submitted on December 12nd, 2003, that announce on June 28th, 2005; No. the 6th, 813,010, United States Patent (USP) " Personal Identification System " that Kono, Umemura, Miyatake, Harada, Ito and Ueki submitted to September 18 calendar year 2001, that announce on November 2nd, 2004; And Miura, Nagasaka and Miyatake No. the 6th, 993,160, United States Patent (USP) " Personal Identification Device and Method " that submit to September 5 calendar year 2001, that announce on January 31st, 2006.United States Patent (USP) the 6th, 993, Fig. 2, Fig. 3, Fig. 4 and the Fig. 5 in No. 160 described several versions of non-contact type finger vein biology sensor.In a version, the user moves through groove shape slit with hand, and this groove shape slit side in the slit is equipped with the source of infrared radiation, and at opposite side thermal camera is housed; In another version, the user is inserted into a finger in the cavity.This patent does not comprise the discussion of target (finger) scope being measured or being used to proofread and correct the method for out-of-focus image.

United States Patent (USP) the 6th, 813, No. 010 and the 6th, 912, No. the 2005/0185827th, No. 045 and U.S. Patent Application Publication are closely similar, and their claim is not all described non-contacting operation, and claim is not all described rangefinder or proofreaied and correct the device of out-of-focus image.Some claims in these claims have been described clearly and have been utilized physical structure to support finger.The specification of all three patents or patent application comprises following statement: " because the noncontact method is not necessarily favourable aspect cost, processing time and compactedness fully; therefore when keeping above-mentioned noncontact feature, being used for fixing such as the equipment of the required positioning element minimum of the imaging area of finger or hand of being had is practical more ".Therefore, the author has stated the complete non-contacting operation of expectation, because it " reduces to be used by the people of uncertain quantity the possibility of the caused bacillus infection of equipment ".Yet they fail to describe in detail device practicality, that cost is effective and compact of realizing complete non-contacting design.The specification of all these three patents and application also comprises following statement: " provide distance between measuring equipment and the palm to check whether correct optical pickocff is controlled picture catching to slave unit to the height of palm.If highly incorrect, then send incorrect elevation information " to the person of being identified.Yet these specifications do not provide any design details that use for vein pattern biometric sensor about how to make up, optical rangefinder practical, that cost is effective and compact.The author does not describe any optical rangefinder design, and the optical rangefinder design is not attached in the Hitachi product.

Fujitsu biology sensor PalmSecure carries out imaging to the subcutaneous vein pattern of palm; Its latest edition has been proposed in March, 2006.Product information described individual with hand vacantly, flatly keep flat above imager in the prone mode of palm.Yet this product information is not described the method for any measurement target scope, describes the guiding user yet palm is placed on given in the specification as transducer, desired target zone (50 ± 10mm) methods of locating.PalmSecure does not have the target zone measurement capability.When attending U.S. sanitary Society for Information Management trade exhibition in the Colorado in Denver, state of Colorado city conference centre on October 10th, 2006, the limitation of PalmSecure is conspicuous the inventor.On this trade exhibition, Fujitsu employee provides the demonstration of the PalmSecure that is connected to notebook-sized personal computer to the inventor.In order correctly to demonstrate PalmSecure, Fujitsu employee has to utilize Pop-up hand rest or the carriage of not describing in the PalmSecure data.This hand rest limits good scope and horizontal registration place by wrist and each finger being supported on respectively in the groove hand is fixed on.When the inventor asks how Fujitsu employee uses PalmSecure in preferred noncontact mode, given answer is, infrared thermoviewer has certain range-sensitivity, therefore in order to realize operation reliably in the noncontact mode of being propagated, needs the user learning curve.The Fujitsu employee more much more than the general user fails to demonstrate the operation of not using hand rest to the experience of PalmSecure.In fact, in the presentation process of the trade exhibition on October 10th, 2006, even the operation that does not have hand rest in the noncontact mode of never attempting being propagated.PalmSecure is connected to notebook, and computer display does not provide about being scanned the guidance how individuality should be positioned at hand the top of infrared thermoviewer.

The Fujitsu patent application of quoting previously is as No. the 2005/0148876th, U.S. Patent Application Publication " Individual IdentificationDevice " continuation application of the PCT application of submitting on September 3rd, 2002, that Endoh, Aoki, Goto and Watanabe submitted on February 1st, 2005.The claim 1 of US2005148876 described " a kind of imaging device, it can with under the situation that palmistry contacts not carry out imaging to the blood vessel of this hand, this equipment comprises: position/orientation/shape indicating member, it is used to indicate the user to lift his hand; ... ".Claim 1 is very ambiguous about the design and the operation of this indicating member, and accompanying drawing does not all provide any clue of how to operate about this indicating member.Yet claim 13 is expressed more clearly: " individual identification equipment according to claim 1, this equipment comprises: detecting unit, it is used for detecting according to the photographic images of hand the position and/or the direction of this hand at every turn when detecting blood-vessel image; Judging unit, it is used to judge whether the position of detected hand and/or direction be suitable; And notification unit, it is used in the position of hand and/or direction notifies when inappropriate the position of user's hand and/or the direction inappropriate ".Accessory rights requires 13 to be clear that the position of hand and/or direction are directly to measure according to the photographic images of this hand, this means that the horizontal level of hand or rotation utilize the image model identification software to measure.For real contactless vein pattern biometric sensor, the most important parameter that must measure is a target zone; And target zone can not directly determine according to photographic images.The fact that Fujitsu PalmSecure can not operate in real noncontact mode in the presentation process of the trade exhibition on October 10th, 2006 and the screen of notebook are used for the fact about the guidance of target zone, show that PalmSecure does not measure target zone, and the contactless vein pattern biometric sensor of the output practicality never of the biosensor design described in the US2005148876.

The original research of hand vein pattern identification aspect emphasize to use with the contacted physical support of the part of hand to limit target with respect to the target zone of infrared thermoviewer and the importance of horizontal registration.For example, quote as mentioned, Clayden (Fig. 1) has described and a kind ofly has been used for coming the venae subcutaneae of the back of the hand is carried out imaging method by requiring individuality to hold the position reference handle, hand is laterally moved up to it with till the side block contacts then.Think that physical support is for obtaining accurately, accurately, repeatably the result is vital.The analysis of Clayden is based on unaltered basic optical measure theory.Yet the physical support that contacts with palmistry contradicts with the noncontact design object of hand vein imager.From above obvious, for can not with situation that palmistry contacts under the blood vessel of palm or finger is carried out the imaging device of imaging technology requirement be of long duration, but also fail to obtain to provide the equipment of working of this discontiguous imaging.

Summary of the invention

The present invention is by providing electro-optical method and equipment innovation, that cheaply, do not contain moving-member, obtained wherein having eliminated first real contactless hand vein biology sensor, thereby solved problem as described above and advanced technology by the measure error that uncertainty caused of target zone and horizontal registration.In a preferred embodiment, the additional electrooptic block that must add in the infrared thermoviewer module comprises: low power laser diode, collimating lens or collimating mirror, and drive circuit for laser, and for extensive application, about 10 dollars of total cost.Preferably, target is palm, the back of the hand or finger.Preferably, single laser diode (LD) is illumination target in such a way: the pattern of reflected radiation provides the direct measurement to target zone when utilizing traditional vein pattern infrared thermoviewer to watch.Use generates visual signal or audio signal to the real-time analysis of this reflected radiation pattern, and this visual signal or audio signal indication are scanned individual hand is moved to and accurately are placed on the optimum range place.In fact, preferably, instruct be scanned individual with hand be placed on his or her biometric data card on the identical scope place of scope that write down, thereby reduce the false rejection rate significantly.Here, false rejection rate is the reject rate of individuality that the feature that is write down on real features and their the biological data card is complementary.The reducing of false rejection rate allows to make the parameter in the mode identificating software strict more, so also reduced the false acceptance rate receptance of the unmatched individuality of feature that write down on real features and the biological data card that they are held (that is, to).

Another embodiment of the present invention comprises uses ultrasonic transmitter and transducer to come measurement target scope and horizontal registration, generates then to be used to make to be scanned vision indication or the audio frequency indication of individual mobile hand hand accurately is positioned at the optimum range place.Another embodiment that the present invention also has comprises and uses the passive optical rangefinder to come the measurement target scope, generates then to be used to make to be scanned vision indication or the audio frequency indication of individual mobile hand hand accurately is positioned at the optimum range place.The passive optical rangefinder does not need to use any laser diode, or any target illumination device the target illumination device that has existed in traditional vein pattern infrared thermoviewer.

The invention provides a kind of biological vein imaging method, this method comprises: the target of human body partly is placed on the position that the bio-imaging instrument can scan; Determine electronically whether described target is positioned at the intended orientation scope with respect to described imager; Provide the described target of indication in described intended orientation scope or must how move described target so that it enters the signal in the described scope; And when definite described target is in described preset range, utilize described bio-imaging instrument to come described target is scanned.Preferably, described scanning comprises and utilizes the vein imaging instrument to scan.Preferably, described placement comprises finger, palm or the back of the hand of placing the people.Preferably, described placement comprises described finger or described palm is aimed at one or more guide line.Preferably, described one or more guide line forms on the surface that described imager is installed thereon or a little more than this surface.Preferably, have two described guide lines, and described guide line is orthogonal.Preferably, described placement comprises according to vision and indicates the described target part of placing described human body.Preferably, described vision indication comprises one or more figure or photo.Preferably, described vision indication describes to watch from the side and watch from the top hand of the top that correctly is positioned at described imager.Preferably, described determine electronically to comprise light is pointed to described target.Preferably, described sensing comprises laser beam or light-emitting diode light beam is pointed to described target.Preferably, the described laser beam sensing is comprised red visible laser beam is pointed to described target.Preferably, described determine electronically to comprise electronically determine described target whether with the predetermined distance range of described imager in.Preferably, described determine electronically to comprise utilize charge-coupled detector(CCD) (CCD) or CMOS detector array to come to being detected by the radiation of described target reflection.Preferably, described detection comprises the pulse that makes described light and the frame frequency synchronised of described CCD or described CMOS detector.Preferably, this method also comprise calculating in succession CCD or the difference between the CMOS frame.Preferably, described sensing comprises a plurality of laser beams or light-emitting diode light beam is pointed to described target.Preferably, describedly provide signal to comprise visual signal or voice signal are provided.Preferably, described providing comprises and utilizes one or more light-emitting diode (LED) that visual signal is provided.Preferably, described utilization comprises and uses green diode to indicate described target in described intended orientation scope and use one or more red diodes to indicate and must how to move described target so that it enters in the described scope.Preferably, described determine electronically to comprise the radiation from described target reflection is detected and uses the real-time analysis to described reflected radiation that described signal is provided.Preferably, described target is people's finger, people's palm or back of people's hand, and described providing comprises that the described people of indication moves described finger or hand to place it in optimum distance scope place or the optimum level registration place with respect to described imager.Preferably, describedly determine electronically only to use the radiation that is provided by described bio-imaging instrument to carry out.Preferably, described determine electronically to comprise acoustic energy is pointed to described target and utilizes the acoustic energy of reflection that described signal is provided.

The present invention also provides a kind of bio-imaging system of vein pattern of the target part that is used to write down human body, and this system comprises: energy source, and it points to described target; Detector, it is positioned and detects a part from the described energy of described target reflection; Computer, it is used for the energy of described reflection is carried out real-time analysis, is used to generate the signal of the scope of indicating described target, and is used to provide the vein pattern image of described target; And vision or audio output device, it is provided for helping described target is placed on respect to the indication in the intended orientation scope of described detector in response to described signal.Preferably, described energy source comprises light-emitting diode (LED) or laser.Preferably, described energy source comprises laser diode.Preferably, described energy source is a source of red visible light.Preferably, described detector is charge-coupled detector(CCD) (CCD) or CMOS detector.Preferably, described energy source is the light-pulse generator with the detector frame frequency synchronised of described CCD or described CMOS detector.Preferably, described system also comprises and is used for visual aid that the described target part of described human body is correctly placed with respect to described imaging system.Preferably, described visual aid comprises described target part that described human body is shown one or more figure or the photo with respect to the correct placement of described imaging system.Preferably, the hand of the top that correctly is positioned at described imager is watched and watched from the top to described one or more figure or photo portrayal from the side.Preferably, described system also comprises and is used to help with the described target part of described human body one or more guide line with respect to described imaging system location.Preferably, described system also comprises the indication that is used to use described guide line that the described target part of described human body is correctly located with respect to described imaging system.Preferably, have two described guide lines, and described guide line is orthogonal.Preferably, the described target of described human body partly is people's finger, people's palm or back of people's hand, and described one or more guide line helps the finger tip location with middle finger.Preferably, described visual aid comprises one or more light-emitting diode (LED).Preferably, described visual aid comprise be used to indicate described target in the intended orientation scope green diode and be used to indicate must how to move described target so that it enters one or more red diodes in the described preset range.Preferably, described energy source comprises collimating lens or collimating mirror or condenser lens or focusing mirror.Preferably, described energy source comprises lens or the speculum that produces Gaussian beam profile.Preferably, described energy source comprises lens or the speculum that produces collimated light beam.

The invention provides and be used under the situation of physical constraint that does not use any kind of or hand rest and will be placed on first utility system by the human body parts of imaging with respect to the accurate position of imager.Read following explanation in conjunction with the drawings, many other features of the present invention, purpose and advantage will be apparent from following explanation.

Description of drawings

Fig. 1 shows the figure of palm vein biological recognition system according to the present invention under the situation of looking down the right hand back of the body, and wherein, light-emitting diode display, indicator collet and photo are in the left side of hand, and alignment mark is near the finger tip of middle finger;

Fig. 2 shows according to of the present invention and is used for the schematic diagram palm vein imager, that utilize first preferred embodiment of the rangefinder cheaply that single LD (laser diode) realizes, wherein, hand is placed on the best vertical distance of the top of infrared thermoviewer;

Embodiment when Fig. 3 shows hand and is placed on vertical distance less than optimum distance, among Fig. 2;

Fig. 4 shows the Gaussian beam profile of focussed laser beam, and the shadow region is the occupied district of laser beam, and the y wheelbase between two solid lines is from representing laser linewidth;

Fig. 5 shows according to of the present invention and is used for the schematic diagram palm vein imager, that utilize second preferred embodiment of the laser range finder cheaply that single LD realizes, and wherein, hand is placed on the best vertical distance of the top of infrared thermoviewer;

Fig. 6 provides the schematic diagram according to the preferred embodiment of biometric vein pattern recognition system of the present invention, comprises digital image analysis, man-machine interface and biological data interface;

Fig. 7 shows the figure of finger vena biological recognition system according to the present invention under the situation of looking down the right hand back of the body, and wherein, light-emitting diode display, indicator collet and photo are in the left side of hand, and alignment mark is near the finger tip of middle finger;

Fig. 8 shows according to of the present invention and is used for the schematic diagram finger vena imager, that utilize first preferred embodiment of the rangefinder cheaply that single LD (laser diode) realizes, wherein, finger is placed on the best vertical distance of the top of infrared thermoviewer; And

Fig. 9 shows according to of the present invention and is used for the schematic diagram finger vena imager, that utilize second preferred embodiment of the laser range finder cheaply that single LD realizes, and wherein, finger is placed on the best vertical distance of the top of infrared thermoviewer.

Embodiment

1. the preferred embodiment of palm vein pattern identification

This detailed description of preferred embodiment has been described a kind of electric lighting system and method that is used to improve the performance of the subcutaneous vein pattern imager (preferably hand vein imager, more preferably palm vein imager) that is used for bio-identification.Those skilled in the art can be easily be modified as the subcutaneous vein pattern imager of other parts that are designed to scan human body with the electro-optic device described in this part.The hand vein imager comprises the imager that the vein of adversary's any part (front or the back that comprise palm, the back of the hand or arbitrary finger) carries out imaging.

Fig. 1 described biological recognition system how to be presented on be scanned individuality before; It shows the figure of the back of the hand of looking down the right hand 101.Infrared thermoviewer module 102 is below hand, so with dashed lines is described.The left side of hand is indicator collet 103, photo piece 110 and led module 104, and all these and infrared thermoviewer module 102 are installed on the same desktop; This desktop is 90cm to 95cm above ground level usually.Indicator collet 103 notice is scanned individuality " with the hand 5cm above transducer (2in.) that keeps flat ".Then, indicator collet 103 is indicated these individualities " (1) aims at middle fingertip in the crosspoint of two lines " also " (2) will on hand or be moved to correct vertical range ".Be provided with two guide lines 108 and 109, preferably, these two guide lines 108 and 109 install on the plane of infrared thermoviewer module or a little more than this plane thereon; The part below middle finger of line 108 is depicted as a dotted line.Preferably, guide line is orthogonal.Article one, line 109 be provided for Fig. 1 in the corresponding horizontal direction of vertical direction on the guidance of location finger, and another line 108 be provided for Fig. 1 in corresponding another horizontal direction of horizontal direction on the information of directed finger.Select as another kind, this can be thought of as the crosspoint of the finger tip of finger being aimed at two lines, hand is oriented to this crosspoint, and middle finger along the line 108 is directed rotatably for this crosspoint to brigadier's palmistry.Piece 110 comprises to be described one or more of the hand of correctly placing.Preferably, having two such describing, can be figure or the photo that has been formed on (for example, by printing) on the durable surface.Preferably, these two figure or photo portrayal watch and watch the hand of the top that correctly is positioned at the infrared thermoviewer module from the side from the top.These two photos have increased the ease for use of biological recognition system significantly.For example, the end view of hand has clearly been described the implication of " hand is kept flat ", and the top view of hand has clearly been described the implication of " middle fingertip being aimed at the crosspoint of two lines ".Method and apparatus depicted in figure 1 is placed on ballpark horizontal registration or position with respect to the infrared thermoviewer module with hand.The horizontal registration of hand needn't be accurate fully, only need be enough to make the precision of the part that is used for bio-identification in the visual field of infrared thermoviewer of hand vein pattern.Can utilize the image analysis software of prior art to come adversary's the horizontal registration or the little error of horizontal location to carry out conventional correction, as what in the fingerprint biology sensor, carry out routinely.

There are the finger between the individuality and the scope of pushing degree.Therefore, when the finger tip of middle finger is aimed at guide line 108 and guide line 109, the slightly different part of palm will directly be aligned in the top of infrared thermoviewer module 102.Yet, this difference of the horizontal registration of hand is inessential, and this is because the geometry of the infrared scan instrument system of each the main infrared scan instrument system that is used for the vein pattern that is recorded on the individual bio-identification card is taken during with all use of being used for individual bio-identification is identical.The identical part of being seen with each main scanning instrument of part that scanner when therefore, each uses will be seen palm.

" top 5cm (2in.) " part in the indicator collet 103 represents the target of typical infrared thermoviewer to sensor focal distance.This part in the indicator collet is intended to instruct individuality that hand is placed on ballpark target zone place (that is, in the dynamic range of optical rangefinder); By " roughly ", can predict safely that indicator collet 103 will cause the target range error less than ± 60%, be 50 ± 30mm in this example.Under the situation that does not have rangefinder and indicating device or physical hand support, hand is placed on right-on target zone sentences that to obtain the good focusing of hand vein pattern on infrared thermoviewer be extremely difficult.Note, in Fig. 1, be scanned individuality and can not see infrared thermoviewer.Obviously, the contactless infrared thermoviewer that lacks rangefinder and indicating device does not provide guidance about correct target zone to the user.Under the situation that does not have rangefinder and indicating device, the user of significant proportion can not be on basis repeatably remains on correct target zone place with their hand.The specification of the palm vein imager of prior art is the target zone of regulation 50 ± 10mm (± 20%) usually, and if further reduce the target zone uncertainty, lower bio-identification error rate then can be provided.

7-LED module 104 comprises the indication individuality and will move to improve the element with respect to the target range definition of infrared thermoviewer on hand or down.These elements comprise: (a) literal 105, " mobile hand, upper and lower, good "; (b) indication hand be positioned incorrect six red-light LEDs 106; And the single green light LED 107 of (c) indicating hand to be positioned correctly.If hand is positioned correctly, then only the green light LED 107 at center is lighted.If hand is positioned incorrectly, then a red-light LED 106 in the red-light LED 106 is lighted.6 red-light LED 106 indication hands are not located best, and the indication user moves hand how far to which direction.7-LED display module 104 only is to be used for indicating an individual visual displays placing the many possible visual displays of hand best; The computer screen graphic alphanumeric display is another selection.Select as another kind, the voice that computer produces can indicate individuality that his or her hand is located in the mode of the best.Yet the provider is to instructing and the two multi-element visual display module 104 representatives of position resolution do not need the preferred embodiment at the independently bio-identification station of local computer or computer display.

Fig. 2 shows the sectional view that keeps flat at the hand 201 of the top of infrared (IR) imager module 102 and laser diode module 203.And, described the two-dimensional digital image of exporting by the signal processing electronic device that is embedded in the infrared thermoviewer module 204 among Fig. 2.Palmar aspect is downward, in the face of IR imager module 102 and laser module 203.Infrared thermoviewer module 102 comprises: two-dimensional CCD or CMOS detector array 208; Be used for hand is focused on lens or the mirror system 206 that detector array lists; Prevent that thereby visible radiation from arriving the long pass infrared filter 205 that detector array reduces background illumination; The IR LED submodule 207 of hand and subcutaneous vein pattern is used to throw light on; Signal processing electronic device 216; And sensor outer housing 209.LED submodule 207 comprises: a plurality of target illumination IR LED that send the radiation of 740nm to 780nm usually; Usually see through the long pass infrared filter 205 of wavelength greater than the radiation of 700nm.

Fig. 2 has described cheaply, has been used for the measurement target scope (promptly, distance from palm to infrared thermoviewer) system, so that computer shown in Fig. 6 or microprocessor can be explained range information, use this information to come the indication user is driven with the light-emitting diode display 104 (Fig. 1) that hand is positioned at the optimum range place moving on hand or down then.This optimum range is represented the poly-distance of the best of hand vein imager.Preferred embodiment has been utilized laser diode (LD) module 203 by the ruddiness LD 210 (for example, Hitachi HL6501MG) that launches at 655nm to 660nm place and collimating lens or collimating mirror 211 compositions.Select as another kind, can also use light-emitting diode to come instead of lasers.Surface through collimated laser light bundle 214 irradiation palms produces red visible light spot thus, and this hot spot is imaged onto on the detector array 208 and as the image patch in the digital picture 204 215 and occurs.Term " through what collimate " is meant that lasing beam diameter is roughly the same, with the range-independence of distance LD.Dotted line 213 has been described the border of infrared thermoviewer visual field, and dotted line 212 has been described the optical axis at the center of this visual field.For example, as shown in Figure 2, LD is aimed at collimating lens, so that be positioned at optimum distance (scope) with the IR imager when locating when palm, through the surface of the palm of the center of the visual field of collimated laser light bundle irradiation IR imager.In this case, be imaged onto on the detector from the laser facula of palmar, and as the image patch 215 at the center of digital frame 204 and occur.In this example, computer or microprocessor (Fig. 6) the driving LED display 104 that is used for the vein pattern graphical analysis located in correct height (scope) with the indication hand.

Red visible LD radiation is not as infrared LED or LD radiation transdermal like that effectively; Therefore, red visible LD utilizes the reflection at skin surface place that more sharp-pointed range definition is provided.The image of the reflect red LD hot spot that skin surface provided is sharp-pointed like that not as the image of being seen when target is paper or other solid object; Yet, be enough sharp-pointed from the red laser light spot of skin surface reflection, be enough to target zone accurately be limited to than the palm vein imager at prior art provide ± the more accurate scope of standard of 1cm in; The range definition of ruddiness LD is better than 0.5cm.For make CCD or CMOS detector array can measure from the surface reflection of skin, from the radiation of red visible LD, the long pass filter 205 of imager module must be changed over the wavelength that allows to see through greater than 650nm, rather than common 700nm.The change that this of filter cutoff wavelength is little can not cause adverse influence to the performance of imager module.

Except hand was positioned in the fact less than the scope place of optimum range, Fig. 3 and Fig. 2 were identical.This makes red laser bundle through collimation at the left side of infrared thermoviewer optical axis irradiation hand, this cause from the red laser light spot of palmar as 215 left sides that appear at the center of digital picture.Red laser light spot as 215 with the distance at the center of digital picture with coverage error, maybe hand must be moved up and be directly proportional with the distance that reaches optimum range.Image analysis calculation machine shown in Fig. 6 or microprocessor provide the light-emitting diode display 104 necessary information that are used for driving Fig. 1 to the direct analysis of digital picture.Driving LED display 104 must move up hand and how far probably moves to indicate.

Opposite is, be easy to find out, if hand is positioned in the scope place greater than optimum range, then from the red laser light spot of palmar as 215 right sides that will appear at the center of digital picture.In this case, the direct analysis to digital picture will cause driving LED display 104 to indicate moving and general how far the moving that must will hand down.

In a preferred embodiment, red visible LD is pulse, with the frame frequency synchronised of CCD/CMOS detector.This allows the AC coupling of CCD/CMOS detector effectively, thereby has eliminated the influence of background emission constant or that become slowly.When utilizing attached computer or microprocessor (shown in Fig. 6) when calculating the difference between the CCD/CMOS frame in succession, even meeting the low-down LD power level of eye-safe standard, also will from the background emission that becomes slowly, clearly highlight from the pulsed red visible of skin reflex.If with frame number (for example, frame 1, frame 2, frame 3, frame 4 etc., wherein, the 1st, first frame that is write down), then frame asks the difference scheme to comprise difference between difference, frame 2 and the frame 3 that calculates between frame 1 and the frame 2 etc. according to the time sequencing of record frame.To provide below and be used for the preferred sequence that operating equipment has the incident of the subcutaneous hand vein pattern imager laser range finder shown in Fig. 2 and Fig. 3, improved.It should be recognized by those skilled in the art that the sequence of events that has utilizable several alternatives.Preferred sequence comprises:

(1) make pulsed red visible LD normal power-up, this represents target acquisition mode.

(2) the AC signal that calculates being subtracted each other by picture frame that will be in succession continuously of the CCD/CMOS detector that is associated with computer or microprocessor is checked.When in the visual field of LD hot spot at detector of target reflection, easily detect the existence that is suspended near the target the vein pattern sensor by the existence of discerning this flare.

(3) utilize visual signal or audio signal, instruct to be scanned the individual optimum target range that hand is moved to the vein pattern sensor top.

(4) when hand is positioned in the optimum target range place, make pulsed red visible LD outage, so that it can not disturb the vein pattern image acquisition.

(5) infrared LED of imager module is switched on, catch the image of subcutaneous vein pattern, and this real-time vein pattern image is compared with the image on being recorded in individual biological data card.Then, this individuality is accepted or refused to biological recognition system.

Existence is based on second decision design of laser range finder single LD, that be used for the biometric vein pattern imager.In this second preferred embodiment, graphical analysis is more complicated; Yet it provides following advantage: will the laser range finder beam alignment not become the vertical axis with respect to infrared thermoviewer to become accurate angle.Fig. 4 has described the operating principle based on laser range finder design relation, alternative between lasing beam diameter and the distance (to the scope of target).Fig. 4 is the accurate diagrammatic representation of the Gaussian beam profile of focussed laser beam 301.Beam diameter at the focus place or 302 places with a tight waist reach minimum, then, in downstream expansion with a tight waist or disperse.Originally beam diameter is non-linear with the increase of distance, then, and along with approach linear function progressively away from a tight waist 302.When scope that hand the is inserted into divergencing laser bigger than waist is intrafascicular, be imaged onto the diameter of the reflected spot size on the infrared vein pattern imager and be directly proportional with distance apart from laser beam waist 302, this is the direct measurement to target zone.

Fig. 5 has described to be used for the realization of second preferred embodiment of laser range finder of the bio-imaging instrument of palm vein pattern identification.Fig. 5 is similar to Fig. 2, and difference is: (a) laser beam 218 is focused lens 217 and is focused into waist 219 in the distance less than the minimum target scope, rather than collimated; And (b) laser beam is approximately perpendicular, rather than with the vertical optical axis 212 of infrared thermoviewer crustal inclination at angle.In second preferred embodiment of laser range finder, the position of reflected laser light spot 215 in digital picture 204 be not important aspect.The diameter of the reflected laser light spot in the digital picture produces the direct measurement to the scope that arrives target.Based on the guidance that the example of first preferred embodiment of front and the indicator collet 103 from Fig. 1 provide, the minimum target scope is 40% (or 20mm) of 50mm.In this example in front, optimum target range is 50mm, this cause utilizing computer among Fig. 6 or microprocessor module 502 and on digital picture reflected laser light spot diameter D2 that determine, that record.If hand is remained in the divergent laser beam less than the target zone place of optimum range, then the diameter D1 of the flare of Chan Shenging is less than D2; This fact is used for driving LED display 104 and indicates hand to be positioned to such an extent that be lower than optimum range and hand must be moved up.Opposite is, when hand being remained on the intrafascicular target zone place greater than optimum range of divergencing laser, the diameter D3 of the flare of generation is greater than D2; This fact is used for driving LED display 104 and indicates hand to be positioned to such an extent that be higher than optimum range and must will hand down moving.

Can also laser beam be focused on according to the mode that makes waist appear at greater than the target zone place of the maximum target scope of 160% (or 80mm) of 50mm.In this case, hand always blocks the laser beam of convergence.The diameter that appears at the reflected spot size in the digital picture 204 will produce the direct measurement to target zone once more; Yet the diameter and the target zone of hot spot are inversely proportional to, the less bigger target zone of spot diameter indication.

Fig. 6 is the schematic diagram of preferred vein pattern identification biological recognition system.Infrared thermoviewer module 102 is obtained digital picture 204 and is sent it to computer or microprocessor module 502, computer or microprocessor module 502 be driving LED display module 104 successively, LED display module 104 drives human brain/hand 504, make staff change target zone, this has produced the closed loop feedback by infrared thermoviewer module 102, till hand (target) is moved to optimum range.In addition, biological data card reader 505 is provided to the input of computer or microprocessor module 502, and the vein pattern that computer or microprocessor module 502 will be stored on the biological data card compares with biometric scan to the subcutaneous vein pattern of individuality.The output of final system be about bio-identification pass through/fail 506, this can utilize Visual Display or audio frequency to show to come to telex network and/or to computer network communication.Biological by or positive identification allow individuality to enter safety means, data file, building, bank account, airborne vehicle etc.

2. the preferred embodiment of finger vena pattern identification

The preferred embodiment of finger vena pattern identification is similar to the preferred embodiment of palm vein pattern identification, and very little modification is only arranged.

Fig. 7 is the version of slightly revising of Fig. 1, and only difference is that infrared thermoviewer module 112 utilizes the vein pattern of middle finger to carry out bio-identification in the centered beneath of middle finger.Preferably, indicator collet 103 is modified to and comprises following message: when finger is positioned in correct horizontal registration place, is scanned individuality and can't see ruddiness from the rangefinder LD shown in Fig. 8 or Fig. 9.

Fig. 8 (version of slightly revising of Fig. 2) show will point 701 keep flat at infrared (IR) imager module 102 and laser diode module 203 the top time the sectional view of finger 701.Also described the two-dimensional digital image 204 exported by the signal processing electronic device that is embedded in the infrared thermoviewer module among Fig. 8.Palmar aspect is downward, in the face of IR imager module 102 and laser module 203.Infrared thermoviewer module 102 comprises: two-dimensional CCD or CMOS detector array 208; Be used for finger is focused on lens or the mirror system 206 that detector array lists; Long pass infrared filter 205, it stops visible radiation to arrive detector array, thereby reduces background illumination; The IR LED submodule 207 of finger and subcutaneous vein pattern is used to throw light on; Signal processing electronic device 216; And sensor outer housing 209.LED submodule 207 comprises a plurality of target illumination IR LED.In this case, be imaged onto on the detector, and occur as the image patch 215 at the center of digital frame 204 from finger laser light reflected hot spot.In this example, computer or the microprocessor (Fig. 6) that is used for the vein pattern graphical analysis indicates finger to locate in correct height (scope) driving LED display 104.

If finger is positioned in distance (similar to situation depicted in figure 3) less than optimum target range, then reflected laser light spot will be positioned at the left side of infrared thermoviewer optical axis, cause red laser light spot as 215 left sides that appear at center on the digital picture.Driving LED display 104 is indicated and hand must be moved up and how far probably move.

Opposite is, if finger is positioned in the scope place greater than optimum range, then from the red laser light spot of finger reflection as 215 right sides that will appear at the center of digital picture.In this case, will cause driving LED display 104 to be indicated to hand down moving and general how far moving to the direct analysis of digital picture.

Fig. 9 is the version of slightly revising of Fig. 5, and Fig. 9 has described to be used for the realization of second preferred embodiment of laser range finder of the bio-imaging instrument of finger vena pattern identification.Fig. 9 is also similar to Fig. 8, and only difference is: (a) laser beam 218 is focused lens 217 and is focused into waist 219 in the distance less than the minimum target scope, rather than collimated; And (b) laser beam is approximately perpendicular, rather than with the vertical optical axis 212 of infrared thermoviewer crustal inclination at angle.In second preferred embodiment of laser range finder, the position of reflected laser light spot 215 in digital picture 204 is unimportant.But the diameter of reflected laser light spot in digital picture produces the direct measurement to the scope that arrives target.Based on the guidance that the example of first preferred embodiment of front and the indicator collet 103 from Fig. 1 provide, the minimum target scope is 40% (or 20mm) of 50mm.In this example in front, optimum target range is 50mm, cause utilizing computer among Fig. 6 or microprocessor module 502 and on digital picture reflected laser light spot diameter D2 that determine, that record.If hand is remained in the divergent laser beam less than the target zone place of optimum range, then the diameter D1 of the flare of Chan Shenging is less than D2; This fact is used for driving LED display 104 and indicates hand to be positioned to such an extent that be lower than optimum range and hand must be moved up.Opposite is, when hand being remained on the intrafascicular target zone place greater than optimum range of divergencing laser, the diameter D3 of the flare of generation is greater than D2; This fact is used for driving LED display 104 and indicates hand to be positioned to such an extent that be higher than optimum range and must will hand down moving.

Can also laser beam be focused on according to the mode that waist is appeared at greater than the target zone place of the maximum target scope of 160% (or 80mm) of 50mm.In this case, hand always blocks the laser beam of convergence.The diameter that appears at the reflected spot size in the digital picture 204 will produce the direct measurement to target zone once more; Yet the diameter and the target zone of hot spot are inversely proportional to, the less bigger target zone of spot diameter indication.

It should be recognized by those skilled in the art that the laser range finder design that has the alternative of using for the biometric vein pattern imager; For example, use the rangefinder of the linear array of a plurality of LD or LD.Described two single laser rangefinder designs are very accurate and practical, direct and economical; Therefore, as two preferred embodiments it is described in detail.Similar is to it should be recognized by those skilled in the art that when using described teaching existence is used to realize being used for the method and apparatus accurate horizontal registration biometric vein pattern imaging, the adversary, alternative.

Described practical, cost is effective, accurate and user-friendly biological recognition system.Should be appreciated that shown in the accompanying drawing and this specification described in specific embodiment be for exemplary purposes, and it should be construed to restriction of the present invention to describing in the following claims.For example, although described the embodiment that the vein of palm is carried out the imaging aspect, this system also can be used for the vein of the back of the hand or finger is carried out imaging.In addition, clearly, those skilled in the art can be under the situation that does not deviate from notion of the present invention carry out multiplely using and revising to described specific embodiment.Equivalent configurations and processing can substitute described various structure and processing; The son of method of the present invention is handled and can be undertaken by different orders in some cases; Perhaps can use various material and element.For example, the LED optical system can substitute above-mentioned laser optical system.

Claims (42)

1. biological vein imaging method, this method comprises: the target part (201) of human body is placed on the position that bio-imaging instrument (102) can scan; Described method is characterised in that and comprises: determine electronically whether described target is positioned at the intended orientation scope with respect to described imager; Provide the described target of indication in described intended orientation scope or must how move described target so that it enters the signal in the described scope; And when definite described target is in described preset range, utilize described bio-imaging instrument to come described target is scanned.

2. method according to claim 1, wherein, described scanning comprises and utilizes the vein imaging instrument to scan.

3. method according to claim 2, wherein, described placement step comprises finger, palm or the back of the hand of placing the people.

4. method according to claim 3, wherein, described placement step comprises aims at one or more guide line (108,109) with described finger or described palm.

5. method according to claim 4, wherein, described one or more guide line forms on the surface that described imager is installed thereon or a little more than this surface.

6. method according to claim 4 wherein, have two described guide lines, and described guide line is orthogonal.

7. method according to claim 1, wherein, described placement step comprises the described target part of placing described human body according to vision indication (103,110,104).

8. method according to claim 1, wherein, described vision indication comprises one or more figure or photo (110).

9. method according to claim 8, wherein, described vision indication describes to watch from the side and watch from the top hand of the top that correctly is positioned at described imager.

10. method according to claim 1, wherein, the described step of determining electronically comprises points to described target with light (214,218).

11. method according to claim 10, wherein, described sensing step comprises points to described target with laser beam or light-emitting diode light beam.

12. method according to claim 11, wherein, the described step that laser beam is pointed to comprises points to described target with red visible laser beam.

13. method according to claim 12, wherein, the described step of determining electronically comprise determine electronically described target whether with the predetermined distance range of described imager in.

14. method according to claim 10, wherein, the described step of determining electronically comprises utilizes charge-coupled detector(CCD) (CCD) or CMOS detector array (208) to come being detected by the radiation of described target reflection.

15. method according to claim 14, wherein, described detection step comprises the pulse that makes described light and the frame frequency synchronised of described CCD or described CMOS detector.

16. method according to claim 15, this method also comprises: calculate in succession CCD or the difference between the CMOS frame.

17. method according to claim 11, wherein, described sensing step comprises points to described target with a plurality of laser beams or light-emitting diode light beam.

18. method according to claim 1, wherein, the described step that signal is provided comprises provides visual signal or voice signal.

19. method according to claim 18 wherein, describedly provides step to comprise to utilize one or more light-emitting diode (LED) (104) that visual signal is provided.

20. method according to claim 19, wherein, describedly utilize step to comprise to use green diode (107) to indicate described target in described intended orientation scope, and use one or more red diodes (106) to indicate and how to move described target so that it enters in the described scope.

21. method according to claim 1, wherein, the described step of determining electronically comprises the radiation from described target reflection is detected, and uses the real-time analysis to described reflected radiation that described signal is provided.

22. method according to claim 21, wherein, described target is people's finger, people's palm or back of people's hand, and the described step that provides comprises that the described people of indication moves described finger or hand to place it in optimum distance scope place or the optimum level registration place with respect to described imager.

23. method according to claim 1, wherein, the described step of determining electronically only uses the radiation that is provided by described bio-imaging instrument to carry out.

24. method according to claim 1, wherein, the described step of determining electronically comprises points to described target with acoustic energy, and utilizes the acoustic energy of reflection that described signal is provided.

25. the bio-imaging system (102,203) of the vein pattern of a target part that is used to write down human body, this system comprises: energy source (210), and it points to described target; Detector (102), it is positioned and detects a part from the described energy of described target reflection; Described system is characterised in that and comprises: computer (502), and it is used for the energy of described reflection is carried out real-time analysis, is used to generate the signal of the scope of indicating described target, and is used to provide the vein pattern image of described target; And vision or audio output device (104,110), it is provided for helping described target is placed on respect to the indication in the intended orientation scope of described detector in response to described signal.

26. bio-imaging according to claim 25 system, wherein, described energy source comprises light-emitting diode (LED) or laser.

27. bio-imaging according to claim 26 system, wherein, described energy source comprises laser diode.

28. bio-imaging according to claim 25 system, wherein, described energy source is a source of red visible light.

29. bio-imaging according to claim 25 system, wherein, described detector is charge-coupled detector(CCD) (CCD) or CMOS detector (208).

30. bio-imaging according to claim 29 system, wherein, described energy source is the light-pulse generator with the detector frame frequency synchronised of described CCD or described CMOS detector.

31. also comprising, bio-imaging according to claim 25 system, this system be used for visual aid (104,110) that the described target part of described human body is correctly placed with respect to described imaging system.

32. bio-imaging according to claim 25 system, wherein, described visual aid comprises described target part that described human body is shown one or more figure or the photo (110) with respect to the correct placement of described imaging system.

33. bio-imaging according to claim 32 system, wherein, the hand of the top that correctly is positioned at described imager is watched and watched from the top to described one or more figure or photo portrayal from the side.

34. also comprising, bio-imaging according to claim 25 system, this system be used to help with the described target part of described human body one or more guide line (108,109) with respect to described imaging system location.

35. also comprising, bio-imaging according to claim 34 system, this system be used to the indication (103) of using described guide line that the described target part of described human body is correctly located with respect to described imaging system.

36. bio-imaging according to claim 34 system wherein, have two described guide lines, and described guide line is orthogonal.

37. bio-imaging according to claim 34 system, wherein, the described target of described human body partly is people's finger, people's palm or back of people's hand, and described one or more guide line helps the finger tip location with middle finger.

38. bio-imaging according to claim 31 system, wherein, described visual aid comprises one or more light-emitting diode (LED) (104).

39. according to the described bio-imaging of claim 38 system, wherein, described visual aid comprises and is used to indicate the green diode (107) of described target in the intended orientation scope, and is used to indicate and must how moves described target so that it enters one or more red diodes (106) in the described preset range.

40. bio-imaging according to claim 25 system, wherein, described energy source comprises collimating lens (211) or collimating mirror or condenser lens or focusing mirror.

41. according to the described bio-imaging of claim 40 system, wherein, described energy source comprises lens or the speculum that produces Gaussian beam profile (301).

42. according to the described bio-imaging of claim 40 system, wherein, described energy source comprises lens (211) or the speculum that produces collimated light beam (214).

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