CN105376469A - Drive automatic focusing method used for biometric features recognition mobile terminal - Google Patents

Abstract

The invention provides a drive automatic focusing method used for a biometric features recognition mobile terminal. The drive automatic focusing method comprises the following steps of 1) defining a to-be-searched partial region of interest and searching parameters based on a preset focusing work object distance range; 2) controlling an optical imaging lens to drive an automatic focusing optical imaging lens to perform continuous focal position search in a monotonous direction based on the to-be-searched partial region of interest and the searching parameters defined in the step 1); 3) controlling an image sensor to obtain imaging original image pixel data output after the continuous focal position search in the monotonous direction in the step 2); 4) calculating focus quality of a focal position search image I {Pi, i=1, NO} in real time and assessing the focus quality; and 5) judging an image corresponding to the optimal focus quality as the optimal focusing image.

Description

A kind of driving auto focusing method for living things feature recognition mobile terminal

Technical field

The present invention relates to bio-identification photoelectric field, especially a kind of mobile terminal visible ray for high security and bio-identification combination photoelectric imaging system and method.

Background technology

Mobile terminal comprises smart mobile phone, flat board, wearable device etc., present information technology mobile development trend, and mobile terminal device is necessarily following is suitable for equipment the most widely.

At present, mobile terminal in real world applications pays at mobile security, account safety logs in, use extremely extensive in Web bank, as the utilization of the aspects such as remaining sum treasured, micro-letter, bank account management, although in its use procedure, for life brings great convenience, but a kind of novel economic crime rise gradually undertaken by features such as security of mobile terminal energy weaknesses.

And in mobile terminal, the customary means that prior art carries out identity validation is exactly Password Input, but the means security performance of this identity validation very low, only need to implant simple Virus on mobile terminals, just this password can be revealed, cause corresponding loss.In order to address this problem, still carry out mobile terminal safety authentication by the mode of bio-identification in the world; As the fingerprint identification technology based on the exploitation of AuthenTec company that Apple proposes, this Technology application, on mobile phone terminal, greatly improves the identity validation fail safe of mobile terminal; But, in the process of fingerprint technique identification, because fingerprint is static, although have uniqueness, but be also extremely easily acquired finger print information, even be imitated, so along with fingerprint technique utilization on mobile terminals more and more extensive, its fail safe also can be on a declining curve accordingly, so the bio-identification more in fail safe with advantage solves very effective method in mobile terminal safety authentication procedures, and biological recognition system is that in existing bio-identification, accuracy is the highest.

At present in all mobile terminals in biological recognition system technology and product, not have the visible ray photo electric imaging system that realizes being used for Self-timer and iris vein biometric identification photo electric imaging system to combine.If but the visible ray photo electric imaging system of Self-timer and the combination of iris vein biometric identification photo electric imaging system separately independent realization, its cost increases greatly, and the volume of main mobile terminal cannot provide accommodation 3 to overlap and separate the installing space of Individual optical imaging system above.

Although iris vein bio-identification in false proof divine force that created the universe fail safe more has advantage compared with fingerprint recognition in addition, if but large-scale application moves the important events such as wholesale payment in such as mobile phone, still need further to upgrade the security technique of false proof divine force that created the universe In vivo detection, the threat eliminated safe hidden trouble.The object of bio-identification own is exactly for safety after all, and itself fail safe is that most fundamental sum is most important.

And in mobile terminal application, how to obtain the formation method of high-quality image light Electrical imaging method and raising bio-identification success rate.

It may be noted that and adopt RGB-IR autonomous channel photo electric imaging system, can realize visible ray and bio-identification combined imaging, but it is in view of production cost and technique at present, the mutual wavelength background isolation between autonomous channel or the cut-off degree of depth also fail practical requirement.

Further, the mobile terminal visible ray of high security and bio-identification combination photoelectric imaging system and method need to solve following serious problem:

1, visible ray and bio-identification combination photoelectric imaging system in mobile terminal application, meet the visible ray photo electric imaging system of Self-timer and the combination of iris vein biometric identification photo electric imaging system, its fixing fabric structure in 8.5mm*8.5mm*6mm, low-power consumption.

2, visible ray and bio-identification combination photoelectric imaging system in mobile terminal application, need the false proof divine force that created the universe biopsy method of a whole set of high security, ensure the fail safe of bio-identification itself.

3. visible ray and bio-identification combination photoelectric imaging system in mobile terminal application, need to obtain high-quality image light Electrical imaging method.

4, visible ray and bio-identification combination photoelectric imaging system in mobile terminal application, need the formation method of a set of raising bio-identification success rate.

5, visible ray and bio-identification combination photoelectric imaging system in mobile terminal application, need greatly to reduce costs, cost could be applied within being reduced to 10 U.S. dollars on a large scale.

Overcoming the above problems is the ultimate challenge faced at present.

Summary of the invention

The technical problem to be solved in the present invention provides a kind of mobile terminal visible ray for high security and bio-identification combination photoelectric imaging system.

Special explanation, the bio-identification that the present invention narrates is appointed as iris and vein.

In order to solve the problems of the technologies described above, the invention provides a kind of mobile terminal visible ray and bio-identification combination photoelectric imaging system, comprising visible ray photoelectronic imaging and bio-identification photo electric imaging system; Described visible ray photoelectronic imaging and bio-identification photoelectronic imaging are by processor chips, LED illumination light source, optical filter, optical imaging lens, imageing sensor composition; The imaging array of described imageing sensor is configured to the imaging wavelength spectrum that unit pixel has reception visible ray-infrared light broadband distribution; Described LED illumination light source is configured to the LED illumination light source of the radiating visible light-near infrared imaging wavelength by LED current driver control, and this LED illumination light source has the radiated wavelength range mutually mated with the visible ray of imageing sensor-infrared light broadband imaging Wavelength distribution;

Described optical filter is configured to the visible ray-infrared light variable wavelength optics filter controlled by optical filter control and drive system; Described visible ray-infrared light variable wavelength optics filter is configured to have the wavelength-filtered scope of mutually mating with imageing sensor visible ray-infrared light broadband imaging Wavelength distribution; Described optical imaging lens is configured to the automatic focus optical imaging lens controlled by optical imaging lens focus driver; Described automatic focus optical imaging lens is configured to have the focusing wave-length coverage of mutually mating with the visible ray of imageing sensor-infrared light broadband imaging Wavelength distribution; Described visible ray-infrared light variable wavelength optics filter, automatic focus optical imaging lens, the optical centre of imageing sensor is configured to the coaxial light path position of imaging system optic axis; The optical centre of described LED illumination light source be configured to imaging system optic axis from axial light path position.

Improvement as to a kind of mobile terminal visible ray of the present invention and bio-identification combination photoelectric imaging system: by described LED illumination light source radiating visible light imaging wavelength, visible ray-infrared light variable wavelength optics filter switches to filtering infrared light imaging wavelength, and the imaging array of automatic focus optical imaging lens physics Refractive focusing visual light imaging wavelength and imageing sensor receives the optical path that visible wavelength forms visible ray photoelectronic imaging; By described LED illumination light source irradiating infrared light imaging wavelength, visible ray-infrared light variable wavelength optics filter switches to visible light imaging wavelength, and the imaging array of automatic focus optical imaging lens physics Refractive focusing near infrared imaging wavelength and imageing sensor receives the optical path that infrared light wavelength forms bio-identification photoelectronic imaging; Described visible ray photoelectronic imaging adopts visual light imaging wavelength to be 400-650nm, and focusing task object distance WD is at least in the scope of 30-100cm; Described bio-identification photoelectronic imaging adopts near infrared imaging wavelength to be 750-950nm, and focusing task object distance WD is at least in the scope of 30-100cm; Described coaxial light path position is visible ray-infrared light variable wavelength optics filter, automatic focus optical imaging lens, and between the optical centreline of imageing sensor and imaging system optic axis, angle has 0 degree of angle; Described is that between the radiation optical centerline of lighting source and imaging system optic axis, angle has 5-30 degree angle from axial light path position.

Further improvement as to a kind of mobile terminal visible ray of the present invention and bio-identification combination photoelectric imaging system: described bio-identification photoelectronic imaging has following optical imagery and requires: the imaging wavelength WI of bio-identification photoelectronic imaging meets: 750nm≤WI≤950nm; The focusing task object distance WD of bio-identification photoelectronic imaging meets: 10cm≤WD≤30cm; The pixel spatial resolution PSR of bio-identification photoelectronic imaging meets: PSR >=10pixel/mm; The optical magnification OM of bio-identification photoelectronic imaging meets: OM=PS*PSR; Wherein, described PS is the physical size of each imaging pixel cell of imageing sensor; PSR is the pixel spatial resolution of bio-identification photoelectronic imaging; The optical space resolution OSRI of described bio-identification photoelectronic imaging meets in image space plane: when equaling 60% at modulation transfer function, 1/ (4*PS)≤OSRI≤1/ (2*PS); Described visible ray photoelectronic imaging has following optical imagery requirement: the imaging wavelength WI of visible ray photoelectronic imaging meets: 400nm≤WI≤650nm; The focusing task object distance WD of visible ray photoelectronic imaging meets: 30cm≤WD≤100cm; The pixel spatial resolution PSR of visible ray photoelectronic imaging should meet: PSR≤3pixel/mm; The optical magnification OM of visible ray photoelectronic imaging, should meet: OM=PS*PSR; Wherein, the above PS is the physical size of each imaging pixel cell of imageing sensor; PSR is the pixel spatial resolution of visible ray photoelectronic imaging;

The optical space resolution OSRI of described visible ray photoelectronic imaging meets in image space plane: when equaling 60% at modulation transfer function, 1/ (4*PS)≤OSRI≤1/ (2*PS).

Preferably, described imageing sensor, LED current driver, automatic focus optical imaging lens focus driver and optical filter control and drive system control by processor chips;

Described processor chips are configured to for connection layout image-position sensor, the image pixel value data that control chart image-position sensor imaging array exports; Connect LED current driver drives and control LED illumination light source radiation intensity, angle of radiation and position, radiated time; Connect automatic focus optical imaging lens focus driver to realize driving automatic focus optical imaging lens physics to focus on; And connect optical filter control and drive system realization driving visible ray-infrared light variable wavelength optics filter wavelength scope change.

Further improvement as to a kind of mobile terminal visible ray of the present invention and bio-identification combination photoelectric imaging system: the physical size PS receiving the imaging pixel cell of visible ray-infrared light wavelength in the imaging array of described imageing sensor meets following condition: 1um/pixel≤PS≤3um/pixel; The wavelength pixel cell that described imageing sensor imaging array receives has the numerical value Y of opto-electronic conversion, and its numerical value Y is:

Y＝Q*GAIN*EXP*ADCG*E*PSUEQ1

Wherein: described EXP is the time of integration or the time for exposure of imageing sensor imaging array; EXP synchronously equals LED illumination light source radiated time; EXP≤33.3ms; GAIN is the Digital and analog gain of imageing sensor imaging array; Maximum GAIN meets the signal to noise ratio snr of imageing sensor, SNR >=36db decibel; ADCG is the ADC voltage analog-numerical value conversion quantization resolution of imageing sensor imaging array; E is radiance or the radiant illumination of the reception of imageing sensor imaging array;

E＝C*β*I/WD ²*cos ²ψ*(1/FNO) ²

Wherein: I is LED illumination light source 106 radiation intensity; The minimum value of I meets I >=100mw/sr; ψ is the angle of radiation of LED illumination light source, namely between the radiation optical centerline of LED illumination light source and imaging system optical axis from axle clamp angle; ψ meets: 5 degree≤ψ≤30 degree; WD is the focusing task object distance of optical imaging system; FNO is the numerical aperture of automatic focus optical imaging lens, and namely relative opening is apart from reciprocal; FNO meets: 0.5*PS/ (1.22* λ)≤FNO≤2.0*PS/ (1.22* λ);

λ is imaging wavelength; β is the biological organism optical effect reflectivity of imaging object; C is the optical coefficient of optical imaging system;

C＝1/16*cos ⁴ω/(1+OM) ²；

Wherein: ω is the field angle of object of incident light; ω meets: 0≤ω≤FOV/2, FOV is the full filed angle of photo electric imaging system; OM is the optical magnification of photo electric imaging system; PSU is the physical size square measure ratio of the imaging pixel cell of imageing sensor imaging array;

PSU＝(PS*PS)/cm ²；

Q is photo electric imaging system opto-electronic conversion constant; The digital value Y that described imageing sensor imaging array receives pixel cell opto-electronic conversion is exported by as image original RAW pixel data I{Y}; The imaging array of described imageing sensor is configured to overall frame imaging pattern or rolling row imaging pattern; Described imageing sensor is configured to RAWRGB pixel output format, uses RGB channel compensation gain or the gain of RGB channel balance;

$R={\∫}_{\mathrm{\λ}l}^{\mathrm{\λ}h}r\left(\mathrm{\λ}\right)f\left(\mathrm{\λ}\right)S\left(\mathrm{\λ}\right)L\left(\mathrm{\λ}\right)d\mathrm{\λ}$

$G={\∫}_{\mathrm{\λ}l}^{\mathrm{\λ}h}g\left(\mathrm{\λ}\right)f\left(\mathrm{\λ}\right)S\left(\mathrm{\λ}\right)L\left(\mathrm{\λ}\right)d\mathrm{\λ}$

$B={\∫}_{\mathrm{\λ}l}^{\mathrm{\λ}h}b\left(\mathrm{\λ}\right)f\left(\mathrm{\λ}\right)S\left(\mathrm{\λ}\right)L\left(\mathrm{\λ}\right)d\mathrm{\λ}$

With G channel compensation or balancing gain for standardizing standard, G_GC=1.0; R channel compensation or balancing gain R_GC=G/R; Channel B compensates or balancing gain B_GC=G/B; Described [λ l, λ h] is imaging wavelength range; Described g (λ), r (λ), b (λ) is respectively the photoelectricity conversion quantum efficiency susceptibility Wavelength distribution function of the rgb light spectrum of imageing sensor, f (λ) is the transmissivity Wavelength distribution function of visible ray-infrared light variable wavelength optics filter, the radiance Wavelength distribution function that S (λ) is LED illumination light source; The transmissivity Wavelength distribution function that L (λ) is automatic focus optical imaging lens; Described equivalence adopts with the gain of R channel compensation or channel B compensating gain as normalizing standard; The image resolution ratio ROI of described imageing sensor is configured to: ROI >=2560pixels*1280pixels; Described imageing sensor has chief ray incidence angles CRA (ChiefRayAngle) >=25 degree.

Further improvement as to a kind of mobile terminal visible ray of the present invention and bio-identification combination photoelectric imaging system: described LED illumination light source has: the visible ray of independence or mixed radiation and near infrared imaging wavelength; Half peak of radiation angle of visual field Ω; Described half peak of radiation angle of visual field Ω meets:

Ω≥FOV；

Described FOV is the full filed angle of imaging system;

FOV≥2*arctan((DI*PS)/(2*EFL))；

Wherein: EFL is the equivalent focal length of automatic focus optical imaging lens; DI is the quantity of the image planes diagonal pixels unit of imageing sensor imaging array; PS is the physical size of the pixel cell of imageing sensor imaging array; For one or more different angle of radiation and the position of the imaging viewing field and image quality effect of optimizing photo electric imaging system; For the continuous or pulsed irradiation sessions synchronous with imageing sensor imaging and the radiation intensity of the image quality effect of combined optimization photo electric imaging system; Described LED illumination light source adopts the encapsulation of SMD surface patch.

Further improvement as to a kind of mobile terminal visible ray of the present invention and bio-identification combination photoelectric imaging system: described visible ray-infrared light variable wavelength optics filter has: when changing into visual light imaging wavelength:

Light cutoff rate Fi≤10.0% in visual light imaging wave-length coverage, light cutoff rate Fo >=99.0% outside visual light imaging wave-length coverage,

Or equivalence

Light transmission Ti >=90.0% in visual light imaging wave-length coverage, light transmission To≤1.0% outside visual light imaging wave-length coverage;

When changing near infrared imaging wavelength:

Light cutoff rate Fi≤10.0% near infrared imaging wave-length coverage, light cutoff rate Fo >=99.0% outside near infrared imaging wave-length coverage,

Or equivalence

Light transmission Ti >=90.0% near infrared imaging wave-length coverage, light transmission To≤1.0% outside near infrared imaging wave-length coverage.

Further improvement as to a kind of mobile terminal visible ray of the present invention and bio-identification combination photoelectric imaging system: described automatic focus optical imaging lens is configured to fixed focal length, adopts liquid driven lens, liquid crystal drive lens, VCM voice coil loudspeaker voice coil to drive lens, MEMS to drive in lens, EDOF wave-front phase modulation lens or wafer scale array lenticule any one;

And it has:

Surface maximum reflectivity Rmax≤1.0%, surperficial average reflectance Ravg≤0.3%,

Or equivalence

Surface minimum transmittance Tmin >=99.0%, surperficial average transmittance Tavg >=99.7%;

Described automatic focus optical imaging lens has: focal length EFL, and numerical aperture FNO meets:

2mm≤EFL≤5mm，1.4≤FNO≤2.8；

The optical distortion DOL absolute value of described automatic focus optical imaging lens is configured to: DOL absolute value≤1%;

The relative Coefficient of Utilitization IOR of described automatic focus optical imaging lens is configured to: IOR >=50%;

The central vision brightness of the peripheral field brightness/optical imaging lens of described IOR=optical imaging lens;

Described automatic focus optical imaging lens and imageing sensor are configured to mutually mate chief ray incidence angles CRA.

A kind of formation method for visible ray photoelectronic imaging, comprise the following steps: 1. processor chips are carried out optical filter control and drive system, LED current driver, imageing sensor, automatic focus optical imaging lens focus driver initial work state configures; 2. processor chips control both optical FILTER TO CONTROL driver, LED current driver, imageing sensor, automatic focus optical imaging lens focus driver enters low-power consumption standby or shutdown mode; Processor chips judge whether to need to obtain visual light imaging image, and be go to step 4., no continuation step 3.; 4. processor chips change visible ray-infrared light variable wavelength optics filter by optical filter control and drive system is visual light imaging wavelength; Processor chips control LED current driver drives LED illumination light source and produce visual light imaging wavelength continuously or the radiation of lock-out pulse pattern; The imaging array of processor chips control chart image-position sensor receives the original image RAWRGB pixel data I{Y} of overall frame imaging pattern or the output of rolling row imaging pattern; 5. processor chips are according to imaging original image RAW pixel data I{Y} and pixel cell opto-electronic conversion relation, drive imageing sensor and LED current driver and automatic focus optical imaging lens focus driver, realize FEEDBACK CONTROL; 6. processor chips are respectively to original image RAW pixel data I{Y} interpolation reconstruction and image procossing; 7. processor chips export the image I{r after interpolated reconstruction and image procossing, g, b}; 8. return step 2. to circulate.

A kind of formation method for bio-identification photoelectronic imaging, it is characterized in that, comprise the following steps: 1. processor chips are carried out optical filter control and drive system, LED current driver, imageing sensor, automatic focus optical imaging lens focus driver initial work state configures; 2. processor chips control both optical FILTER TO CONTROL driver, LED current driver, imageing sensor, automatic focus optical imaging lens focus driver enters low-power consumption standby or shutdown mode; 3. processor chips judge whether to need to obtain bio-imaging image, and be go to step (4), no continuation step (3); 4. processor chips change visible ray-infrared light variable wavelength optics filter by optical filter control and drive system is near infrared imaging wavelength; 5. processor chips control LED current driver drives LED illumination light source and produce near infrared imaging wavelength continuously or the radiation of lock-out pulse pattern; 6. the imaging array of processor chips control chart image-position sensor receives the original image RAWRGB pixel data I{Y} of overall frame imaging pattern or the output of rolling row imaging pattern; 7. processor chips are according to imaging original image RAW pixel data I{Y} and pixel cell opto-electronic conversion relation, drive imageing sensor and LED current driver and automatic focus optical imaging lens focus driver, realize FEEDBACK CONTROL; 8. processor chips output image I{Y}; 9. return step (2) to circulate.

As the improvement to a kind of formation method for bio-identification photoelectronic imaging of the present invention, described imageing sensor initial work state is configured to RAWRGB pixel output format, and the gain of RGB channel compensation or RGB channel balance gain process arrange corresponding RGB passage numeral and/or the analog gain simple implementation of imageing sensor by the configuration of initial work state; First, the processor chips imaging original image RAW pixel data I{Y} that can export according to imageing sensor and the formula EQ1 of correspondence described FEEDBACK CONTROL comprises following step:, the reset time of integration of FEEDBACK CONTROL imageing sensor, numeral and/or analog gain are arranged, the radiation intensity of FEEDBACK CONTROL LED current driver drives LED illumination light source, and radiated time, for control chart image brightness, signal to noise ratio and motion blur degree improve image quality; Secondly, minute surface total reflection annoyance level and contrast lightness balanced intensity in the processor chips imaging original image RAW pixel data I{Y} computed image that can export according to imageing sensor, FEEDBACK CONTROL LED current driver drives LED illumination light source is for controlling angle of radiation and position to improve image quality; Finally, processor chips can drive automatic focus optical imaging lens to realize bio-identification photoelectronic imaging focusing task object distance WD at least in the scope of 10cm-30cm according to the focus mass value FEEDBACK CONTROL automatic focus optical imaging lens focus driver calculating image original RAW pixel data I{Y}.

A kind of driving auto focusing method, comprises the following steps: 1. according to predetermined focusing task object distance range, define local region of interest to be searched and search parameter; 2. processor chips control automatic focus optical imaging lens focus driver according to defining local region of interest to be searched and search parameter in step 1, drive automatic focus optical imaging lens to perform and search in continuity from above focal position, dull direction; 3. the imaging original image RAWRGB pixel data exported in processor chips control chart image-position sensor obtaining step 2, is searched in continuity from above focal position, dull direction; 4. processor chips calculate the focus quality of focal position searching image in real time; 5. processor judges that image corresponding to pinpointed focus quality is optimum focusing image.

The false proof divine force that created the universe biopsy method of a kind of bio-identification: adopt the biological tissue's enhanced spectrometry-active characteristic real-time detection method produced by visible ray-near infrared imaging wavelength radiation.

As the improvement to the false proof divine force that created the universe biopsy method of a kind of bio-identification of the present invention, biological tissue's enhanced spectrometry-active characteristic real-time detection method that described visible ray-near infrared imaging wavelength radiation produces, comprises the following steps: 1) processor chips change visible ray-infrared light variable wavelength optics filter by optical filter control and drive system is visual light imaging wavelength; Processor chips drived control LED current driver drives LED illumination light source produces visual light imaging wavelength radiation; Processor chips obtain the visual light imaging wavelength graph of imageing sensor imaging array as Ivs; 2) processor chips change visible ray-infrared light variable wavelength optics filter by optical filter control and drive system is near infrared imaging wavelength; Processor chips drived control LED current driver drives LED illumination light source produces near infrared imaging wavelength radiation; Processor chips obtain the near infrared imaging wavelength graph of imageing sensor imaging array as Iir; 3) in processor chips calculation procedure a, b visual light imaging wavelength graph as Ivs and near infrared imaging wavelength graph as the contrast C data of Iir, be respectively Ivs_C, and Iir_C; Wherein:

C is the contrast between iris region and iris exterior domain;

Or

C is the contrast between venosomes and vein exterior domain;

C＝S(Yiris)/S(Youtiris)；

Or

C＝S(Youtvein)/S(Yvein)；

Yiris represents iris region pixel; Youtiris represents iris exterior domain pixel; Yvein represents venosomes pixel;

Youtvein represents vein exterior domain pixel; Described function S is respective regions pixels statistics valuation functions, and the method that described pixels statistics valuation functions adopts comprises: statistics with histogram, frequency statistics, mean value is added up, weighted average Data-Statistics, middle Data-Statistics, energy value is added up, variance statistic, gradient statistics or space-frequency domain filter; 4) processor chips calculate picture contrast Ivs_C and the Iir_C activity change rate Δ ρ of visual light imaging wavelength radiation and near infrared imaging wavelength radiation respectively in real time;

Wherein:

Δρ＝Iir_C/Ivs_C*100％；

5) according to visible ray-near infrared imaging wavelength radiation biological tissue enhanced spectrometry-active characteristic preset value, with the active contrast respective change rate of data value Δ ρ in step 4, Rule of judgment Δ ρ > 300% realizes detecting biological living state in real time; Described above-mentioned steps 1 and 2 order has equivalence, can exchange.

A kind of formation method improving bio-identification success rate: comprise the following steps: I, gather the near infrared imaging wavelength biometric image Iir{P ψ enroll} that at least two or more LED illumination light source produces when different angle of radiation and position during registration; II, use biometric image Iir{P ψ enroll} to calculate and obtain at least two or more biometric templates Template{P ψ enroll}, carry out intersecting between feature templates after comparison success, save as the biometric templates of registration; The near infrared imaging wavelength biometric image Iir{P ψ recogn} that the LED illumination light source gathering or more when III, identifying produces when different angle of radiation and position; IV, use one or more biometric image Iir{P ψ recogn} to calculate between the feature templates Template{P ψ recogn} of generation with the biometric templates Template{P ψ enroll} of registration to carry out intersecting comparison and obtaining recognition result.

Improve a formation method for bio-identification success rate, it is characterized in that: comprise the following steps: the near infrared imaging wavelength biometric image Iir{Renroll} that when I, registration, the LED illumination light source of collection at least two kinds or more produces when different radiation intensity; II, use biometric image Iir{Renroll} to calculate to obtain at least two or more biometric templates Template{Renroll}, carry out intersecting between feature templates after comparison success, save as the biometric templates of registration; The near infrared imaging wavelength biometric image Iir{Rrecogn} that III, the LED illumination light source gathering or more when identifying produce when different radiation intensity; IV, use one or more biometric image Iir{Rrecogn} calculate produce feature templates Template{Rrecogn} and the biometric templates Template{Renroll} of registration between carry out intersecting comparison and obtaining recognition result.

The near infrared imaging wavelength biometric image Iir{Wenroll} that when a kind of formation method improving bio-identification success rate: comprise the following steps: a registers, the LED illumination light source of collection at least two kinds or more produces when different radiated wavelength range; B uses biometric image Iir{Wenroll} to calculate and obtains at least two or more biometric templates Template{Wenroll}, carries out intersecting between feature templates after comparison success, saves as the biometric templates of registration; The near infrared imaging wavelength biometric image Iir{Wrecogn} that the LED illumination light source that c gathers or more when identifying produces when different radiated wavelength range; Carry out intersecting comparison and obtaining recognition result between the feature templates Template{Wrecogn} that d uses one or more biometric image Iir{Wrecogn} calculating to produce and the biometric templates Template{Wenroll} of registration.

Sum up foregoing description, by present invention achieves the mobile terminal visible ray of high security and bio-identification combination photoelectric imaging system and its method:

1, visible ray and bio-identification combination photoelectric imaging system in mobile terminal application, realizes meeting the visible ray photoelectronic imaging of Self-timer and the combination of multiple iris vein biometric identification photoelectronic imaging, its fixing fabric structure in 8.5mm*8.5mm*6mm, low-power consumption.

2, visible ray and bio-identification combination photoelectric imaging system in mobile terminal application, realize the false proof divine force that created the universe biopsy method of a whole set of high security, ensure the fail safe of bio-identification itself.

3. visible ray and bio-identification combination photoelectric imaging system in mobile terminal application, realize obtaining high-quality image light Electrical imaging method.

4, visible ray and bio-identification combination photoelectric imaging system in mobile terminal application, realize the formation method of a set of raising bio-identification success rate.

5, visible ray and bio-identification combination photoelectric imaging system in mobile terminal application, realize greatly reducing costs, cost can be applied within being reduced to 10 U.S. dollars on a large scale.

Accompanying drawing explanation

Below in conjunction with accompanying drawing, the specific embodiment of the present invention is described in further detail.

Fig. 1 is the overall construction drawing of visible ray of the present invention and bio-identification combination photoelectric imaging system;

Embodiment

Embodiment 1, provide a kind of mobile terminal visible ray and bio-identification combination photoelectric imaging system and method.The method includes the formation method of visible ray photoelectronic imaging, the formation method of bio-identification photoelectronic imaging, biological false proof divine force that created the universe biopsy method, improves the formation method of bio-identification success rate.

As shown in Figure 1, this combination photoelectric imaging system sets gradually visible ray-infrared light variable wavelength optics filter (101 or 104) (for visible light or near infrared imaging wavelength from top to bottom along imaging system optical axis 100, before or after being positioned at automatic focus optical imaging lens 102), automatic focus optical imaging lens 102 (for physics Refractive focusing imaging wavelength), the fixed mounting 103 (for fixedly mounting automatic focus optical imaging lens) of automatic focus optical imaging lens, imageing sensor 105 (exporting image for opto-electronic conversion), lighting source 106 (comprises visible ray and infrared light-LED illumination light source, for visible ray photoelectronic imaging is produced to visual light imaging wavelength radiation and for producing near infrared imaging wavelength radiation to bio-identification photoelectronic imaging) and imaging system fixed installation substrate 107 (for providing visible ray and bio-identification photoelectronic imaging fixed installation carrier), imaging system fixed installation substrate 107 connects Mobile terminal main board 110 (for realizing mobile terminal function circuit carrier), on Mobile terminal main board 110, integrated LED current driver 108 is (for drived control LED illumination light source 106 radiation intensity, angle of radiation and position, and radiated time), automatic focus optical imaging lens focus driver 111 (for driving automatic focus optical imaging lens 102 automatic focus), optical filter control and drive system 112 (changing wave-length coverage for driving visible ray-infrared light variable wavelength optics filter), with processor chips 109 (for drived control LED current driver 108, automatic focus optical imaging lens focus driver 111, optical filter control and drive system 112 and imageing sensor 105).

In the specific embodiment of the invention 1, visible ray and bio-identification combination photoelectric imaging system comprise the optical path of optical path for visible ray photoelectronic imaging and bio-identification photoelectronic imaging.

The optical path of visible ray photoelectronic imaging comprises as follows:

LED illumination light source 106 radiating visible light imaging wavelength, visible ray-infrared light variable wavelength optics filter (101 or 104) switches to filtering infrared light imaging wavelength, automatic focus optical imaging lens 102 physics Refractive focusing visual light imaging wavelength, the imaging array of imageing sensor 105 receives visible wavelength.

The optical path of bio-identification photoelectronic imaging comprises as follows:

LED illumination light source 106 irradiating infrared light imaging wavelength, visible ray-infrared light variable wavelength optics filter (101 or 104) switches to visible light imaging wavelength, automatic focus optical imaging lens 102 physics Refractive focusing near infrared imaging wavelength, the imaging array of imageing sensor 105 receives infrared light wavelength.

In specific embodiments of the invention 1, the imaging array of imageing sensor 105 is configured to the imaging wavelength spectrum that unit pixel has reception visible ray-infrared light broadband distribution; LED illumination light source 106 (visible ray and infrared light LED illumination light source) is configured to have the radiated wavelength range mutually mated with the visible ray of imageing sensor 105-infrared light broadband imaging Wavelength distribution; Visible ray-infrared light variable wavelength optics filter (101 or 104) is configured to have the wavelength-filtered scope of mutually mating with imageing sensor 105 visible rays-infrared light broadband imaging Wavelength distribution; Automatic focus optical imaging lens 102 is configured to have the focusing wave-length coverage of mutually mating with the visible ray of imageing sensor 105-infrared light broadband imaging Wavelength distribution.

Visible ray-infrared light variable wavelength optics filter (101 or 104), automatic focus optical imaging lens 102, the optical centre of imageing sensor 105 is configured to coaxial (on-axis) light path position of imaging system optic axis 100.Coaxially (on-axis) light path position is that between the optical centreline of visible ray-infrared light variable wavelength optics filter (101 or 104), automatic focus optical imaging lens 102 and imageing sensor 105 and imaging system optic axis 100, angle has 0 degree of angle.

The optical centre of LED illumination light source 106 be configured to imaging system optic axis 100 from axle (off-axis) light path position.Be that between the radiation optical centerline of lighting source 106 and imaging system optic axis 100, angle has 5-30 degree angle from axle (off-axis) light path position.

[processor chips 109 have following function:

For connection layout image-position sensor 105, the image pixel value data that control chart image-position sensor 105 imaging array exports;

Connect the radiation intensity of LED current driver 108 drived control LED illumination light source 106, angle of radiation and position, radiated time;

Connect automatic focus optical imaging lens focus driver 111 to realize driving automatic focus optical imaging lens 102 physics to focus on;

Connect optical filter control and drive system 112 to realize driving visible ray-infrared light variable wavelength optics filter wavelength scope to change.

Automatic focus optical imaging lens 102 is configured to fixed focal length, can adopt as liquid driven lens, liquid crystal drive lens, VCM voice coil loudspeaker voice coil drive lens, MEMS to drive in lens, EDOF wave-front phase modulation lens or wafer scale array lenticule any one.

Above-described visible ray-infrared light variable wavelength optics filter (101 or 104) control and drive system 112, can adopt as VCM voice coil loudspeaker voice coil electromagnetic and mechanical power drives 2 independently (visible ray and infrared light) optical filter travel displacement control realization wave-length coverage changes respectively.Concrete, realize electromagnetic force by the current value applying different size at voice coil loudspeaker voice coil cavity and promote the coaxial light path position of shell fragment mechanical transfer actuator travel displacement 2 separate filter difference (visible or infrared light) to imaging system optic axis 100 to realize driving wave-length coverage to change.A nearlyer step, above-described visible ray-infrared light variable wavelength optics filter (101 or 104), can adopt thin dielectric film tunable wavelength optical filter.The tuning optical filter wavelength filter area that realizes of thin film dielectric value being applied different size by optical filter control and drive system 112 is changed.Visible ray of the present invention-infrared light variable wavelength optics filter is not limited to above-mentioned citing, and other types should by equivalent understanding.

It is 400-650nm that the imaging wavelength of invention comprises visual light imaging wavelength, and near infrared imaging wavelength is 750-950nm; It is 400-650nm that imaging wavelength in specific embodiment 1 comprises visual light imaging wavelength, and near infrared imaging wavelength is 810-880nm.The specific embodiment of the invention 1 as an example, near infrared imaging wave-length coverage, imaging wavelength range is bandwidth characteristic in essence, it also can be equal to and is interpreted as and is described by imaging wavelength center (wavelengthcenter) and half-peak band width (FWHM), as 810-880nm scope can be expressed as, centre wavelength 850nm ± 30nm half-peak band width.Further, as imaging wavelength range change citing, can wavelength 850nm ± 15nm half-peak band width centered by arrowband.Imaging wavelength range change of the present invention is not limited to above-mentioned citing, and other scopes should by equivalent understanding.

Visible ray photoelectronic imaging adopts visual light imaging wavelength, and focusing task object distance WD is at least in the scope of 30-100cm, and photo electric imaging system adopts near infrared imaging wavelength, and focusing task object distance WD is at least in the scope of 10-30cm.

Bio-identification photoelectronic imaging has following optical imagery requirement:

The imaging wavelength WI of bio-identification photoelectronic imaging meets: 750nm≤WI≤950nm;

The focusing task object distance WD of bio-identification photoelectronic imaging meets: 10cm≤WD≤30cm;

The pixel spatial resolution PSR (pixelspatialresolution) of bio-identification photoelectronic imaging should meet: PSR >=10pixel/mm;

The optical magnification OM (opticalmagnification) of bio-identification photoelectronic imaging, should meet: OM=PS*PSR;

Wherein, above-described PS is the physical size of each imaging pixel cell of imageing sensor 105; PSR is the pixel spatial resolution of bio-identification photoelectronic imaging;

The optical space resolution OSRI (opticalspatialresolutionofimageofplane) of bio-identification photoelectronic imaging should meet in image space plane: when modulation transfer function equals 60% (MTF=0.6), 1/ (4*PS)≤OSRI≤1/ (2*PS) lp/mm (line is to every millimeter).

Visible ray photoelectronic imaging has following optical imagery requirement:

The imaging wavelength WI of visible ray photoelectronic imaging meets: 400nm≤WI≤650nm;

The focusing task object distance WD of visible ray photoelectronic imaging meets: 30cm≤WD≤100cm;

The pixel spatial resolution PSR (pixelspatialresolution) of visible ray photoelectronic imaging should meet: PSR≤3pixel/mm;

The optical magnification OM (opticalmagnification) of visible ray photoelectronic imaging, should meet: OM=PS*PSR;

Wherein, above-described PS is the physical size of each imaging pixel cell of imageing sensor 105; PSR is the pixel spatial resolution of visible ray photoelectronic imaging;

The optical space resolution OSRI (opticalspatialresolutionofimageofplane) of visible ray photoelectronic imaging should meet in image space plane: when modulation transfer function equals 60% (MTF=0.6), 1/ (4*PS)≤OSRI≤1/ (2*PS) lp/mm (line is to every millimeter).

The physical size PS receiving the imaging pixel cell of visible ray-infrared light wavelength in the imaging array of imageing sensor 105 meets following condition: 1um/pixel≤PS≤3um/pixel (the every pixel of micron);

The numerical value Y of the wavelength pixel cell opto-electronic conversion that imageing sensor 105 imaging array receives is:

Y＝Q*GAIN*EXP*ADCG*E*PSUEQ1

Wherein: above-described

EXP is the integrationTime or the time for exposure exposuretime time of integration of imageing sensor 105 imaging array, unit: S second; EXP synchronously equals LED illumination light source 106 radiated time;

EXP≤33.3ms

GAIN is the Digital and analog gain of imageing sensor 105 imaging array, without unit;

Maximum GAIN meets the signal to noise ratio snr of imageing sensor 105, SNR >=36db decibel

ADCG is the ADC voltage analog-numerical value conversion quantization resolution of imageing sensor 105 imaging array, unit: LSB/V, value bit every volt;

E is radiance or the radiant illumination of the reception of imageing sensor 105 imaging array, unit: lux (lux) or mw/cm2 (every milliwatt every square centimeter);

E＝C*β*I/WD ²*cos ²ψ*(1/FNO) ²

Wherein: I is LED illumination light source 106 radiation intensity, the every surface of sphere of unit milliwatt (mw/sr);

I minimum value meets I >=100mw/sr;

ψ is the angle of radiation of LED illumination light source 106, namely between the radiation optical centerline of LED illumination light source 106 and imaging system optical axis 100 from axle clamp angle;

ψ meets: 5 degree≤ψ≤30 degree; A nearlyer step is restricted to 7 degree≤ψ≤22.5 degree;

WD is the focusing task object distance of optical imaging system;

FNO is the numerical aperture of automatic focus optical imaging lens 102, and namely relative opening is apart from reciprocal;

FNO meets: 0.5*PS/ (1.22* λ)≤FNO≤2.0*PS/ (1.22* λ)

λ is imaging wavelength;

β is the biological organism optical effect reflectivity (wavelength of LED illumination light source radiation through the absorption of iris or vein biometric tissue, reflection and scattering generation biological organism optical effect reflectivity) of imaging object (iris or vein);

C is the optical coefficient of optical imaging system;

C＝1/16*cos ⁴ω/(1+OM) ²

Wherein: ω is the field angle of object of incident light;

ω meets: 0≤ω≤FOV/2, FOV is the full filed angle of photo electric imaging system;

OM is the optical magnification of photo electric imaging system;

PSU is the physical size square measure ratio of the imaging pixel cell of imageing sensor 105 imaging array;

PSU＝(PS*PS)/cm ²；

Q is photo electric imaging system opto-electronic conversion constant; Unit is the every centimeters squared per second of the every milliwatt of volt, V/ (mw/cm ²-sec) or ke-/(mw/cm ²-sec);

The digital value Y of imageing sensor 105 imaging array reception pixel cell opto-electronic conversion is further used as image original RAW pixel data I{Y} and is exported.

The imaging array of imageing sensor 105 is configured to overall frame imaging pattern (GlobalShutter) or rolling row imaging pattern (RollingShutter).

Overall frame imaging pattern (GlobalShutter) described in the specific embodiment of the invention 1 comprises the imaging pattern of overall Frame integration and the reading of overall frame, or the imaging pattern of overall Frame integration and row reading of rolling.

Rolling row imaging pattern (RollingShutter) described in the specific embodiment of the invention 1 comprises the imaging pattern that rolling row anomalous integral rolling row reads.

Imageing sensor 105 is configured to RAWRGB pixel output format, uses RGB channel compensation gain or the gain of RGB channel balance.

$R={\∫}_{\mathrm{\λ}l}^{\mathrm{\λ}h}r\left(\mathrm{\λ}\right)f\left(\mathrm{\λ}\right)S\left(\mathrm{\λ}\right)L\left(\mathrm{\λ}\right)d\mathrm{\λ}$

$G={\∫}_{\mathrm{\λ}l}^{\mathrm{\λ}h}g\left(\mathrm{\λ}\right)f\left(\mathrm{\λ}\right)S\left(\mathrm{\λ}\right)L\left(\mathrm{\λ}\right)d\mathrm{\λ}$

$B={\∫}_{\mathrm{\λ}l}^{\mathrm{\λ}h}b\left(\mathrm{\λ}\right)f\left(\mathrm{\λ}\right)S\left(\mathrm{\λ}\right)L\left(\mathrm{\λ}\right)d\mathrm{\λ}$

With G channel compensation or balancing gain for standardizing standard, G_GC=1.0;

R channel compensation or balancing gain R_GC=G/R;

Channel B compensates or balancing gain B_GC=G/B;

Above-described [λ l, λ h] be imaging wavelength range, in the specific embodiment of the invention 1, preferred citing visual light imaging wavelength is [400nm, 650nm], infrared imaging wavelength is [800nm, 900nm], as equivalent understanding, infrared imaging wave-length coverage further also can be selected to be changed to [810nm, 880nm].

G (λ), r (λ), b (λ) is respectively the photoelectricity conversion quantum efficiency susceptibility Wavelength distribution function of the rgb light spectrum of imageing sensor 105, f (λ) is the transmissivity Wavelength distribution function of visible ray-infrared light variable wavelength optics filter (101 or 104), the radiance Wavelength distribution function that S (λ) is LED illumination light source 106; The transmissivity Wavelength distribution function that L (λ) is automatic focus optical imaging lens 102.

Equivalent to understand, also can of equal valuely to adopt with the gain of R channel compensation or channel B compensating gain as normalizing standard.

When special image imaging sensor 105 adopts monochrome type, RGB channel gain compensates or RGB channel gain balance can be reduced to G_CGC=R_CGC=B_CGC=1.0;

The image resolution ratio ROI of described imageing sensor 105 is configured to:

ROI≥2560pixels*1280pixels。

Described imageing sensor 105 has chief ray incidence angles CRA (ChiefRayAngle) >=25 degree.

Imageing sensor 105 described in the specific embodiment of the invention 1 can adopt BareDie (COB), and the encapsulation such as ShellUTCSP, NeoPACCSP, TSVCSP reduces volume further.

LED illumination light source 106 described in the specific embodiment of the invention 1 has: the visible ray of independence or mixed radiation and near infrared imaging wavelength.Further, the LED illumination light source (106 visible rays and infrared light LED) described in the specific embodiment of the invention 1 has: half peak of radiation angle of visual field Ω.Half described peak of radiation angle of visual field Ω meets:

Ω≥FOV；

Described FOV is the full filed angle of imaging system;

FOV≥2*arctan((DI*PS)/(2*EFL))；

Wherein: EFL is the equivalent focal length of automatic focus optical imaging lens 102; DI is the quantity of the image planes diagonal pixels unit of imageing sensor 105 imaging array; PS is the physical size of the pixel cell of imageing sensor 105 imaging array;

LED (i.e. above-described LED illumination light source) is a kind of lambert's point-source of light of 360 degree of angle radiation light in theory, adopts convex lens or concave mirror that the light refraction of LED point light source radiation or reflection can be made to play and converges the effect that luminous energy controls the half peak of radiation angle of visual field of LED illumination light source.Convex lens can be manufactured by optical substrate materials such as height refraction and transmittance optical plastics, and concave mirror can be manufactured by high optical reflectivity metal matrix material.Further desirable, LED can adopt refraction and the high epoxy resin-matrix material of transmissivity, mix the scattering colorant agent absorbing visible transmission infrared light wavelength and carry out lens function encapsulation, realize the LED half peak of radiation angle of visual field to control to converge luminous energy, and present surface black, to reach visual sense of beauty requirement.

LED illumination light source 106 described in the specific embodiment of the invention 1 has: one or more different angle of radiation and position, for optimizing imaging viewing field and the image quality effect of photo electric imaging system.Be positioned on the left of imaging system optical axis 100 as adopted and/or the different radiation position on right side and different angle of radiation (left side Pl, right side Pr, left and right sides Pl & Pr, in [5-30] angle of radiation, any one or multiple angles are as 5 degree, 20 degree), also (upside Pt can be adopted as different angle of radiation and change in location citing, downside Pb, upper and lower both sides Pt & Pb, in [5-30] angle of radiation, any one or multiple angles are as 10 degree, 30 degree).Multiple angle of radiation can optimize minute surface total reflection light annoyance level, improves the image quality of photo electric imaging system.Multiple radiation position can optimal imaging visual field contrast lightness balanced intensity, improve the image quality of photo electric imaging system.Different angle of radiation of the present invention and change in location are not limited to above-mentioned citing, and other different angle of radiation and position should by equivalent understandings.

LED illumination light source 106 described in the specific embodiment of the invention 1 has: the continuous or pulsed irradiation sessions synchronous with imageing sensor 105 imaging and radiation intensity, for the image quality effect of combined optimization photo electric imaging system.LED illumination light source 106 synchronous with imageing sensor 105 imaging continuously or pulsed irradiation sessions and radiation intensity, can optimized image brightness, signal to noise ratio and motion blur degree, improve the image quality of photo electric imaging system.LED illumination light source 106 can adopt the encapsulation such as SMD surface patch to reduce volume further.

Visible ray described in the specific embodiment of the invention 1-infrared light variable wavelength optics filter (101 or 104) has: change visible ray and near infrared imaging wave-length coverage.Further, the visible ray described in the specific embodiment of the invention 1-infrared light variable wavelength optics filter (101 or 104) has:

When changing into visual light imaging wavelength:

Light cutoff rate Fi≤10.0% in visual light imaging wave-length coverage,

Light cutoff rate Fo >=99.0% outside visual light imaging wave-length coverage,

Or equivalence

Light transmission Ti >=90.0% in visual light imaging wave-length coverage,

Light transmission To≤1.0% outside visual light imaging wave-length coverage.

When changing near infrared imaging wavelength:

Light cutoff rate Fi≤10.0% near infrared imaging wave-length coverage,

Light cutoff rate Fo >=99.0% outside near infrared imaging wave-length coverage,

Or equivalence

[light transmission Ti >=90.0% near infrared imaging wave-length coverage,

Light transmission To≤1.0% outside near infrared imaging wave-length coverage.

Automatic focus optical imaging lens 102 described in the specific embodiment of the invention 1 has: physics Refractive focusing visible ray and near infrared imaging wavelength.Further, the automatic focus optical imaging lens 102 described in the specific embodiment of the invention 1 has visible ray and near infrared imaging wavelength:

Surface maximum reflectivity Rmax≤1.0%, surperficial average reflectance Ravg≤0.3%;

Or equivalence

Surface minimum transmittance Tmin >=99.0%, surperficial average transmittance Tavg >=99.7%.

Above-described automatic focus optical imaging lens 102 can at aspherics plastics as optical grade PMMA, and the optical substrate materials such as optical grade PC carry out surface multi-layer anti-reflection or anti-reflection coating realizes; And realize by 3-5P sheet aspherics plastics Shooting Technique, TTL optics overall length≤6mm.

Described automatic focus optical imaging lens has: focal length EFL, and numerical aperture FNO meets:

2mm≤EFL≤5mm，1.4≤FNO≤2.8。

Further, optical distortion DOL (distortionoflens) absolute value of above-described automatic focus optical imaging lens 102 is configured to:

DOL absolute value≤1%.

The relative Coefficient of Utilitization IOR of above-described automatic focus optical imaging lens 102 is configured to:

IOR≥50％。

The central vision brightness of the peripheral field brightness/optical imaging lens of described IOR=optical imaging lens.

Above-described automatic focus optical imaging lens 102 and imageing sensor 105 are configured to mutually mate chief ray incidence angles CRA, that is, CRA is equal in theory, and in practical application, departure scope absolute value is less than or equal to 3 degree.

Automatic focus optical imaging lens 102 is configured to fixed focal length, comprises liquid driven lens, liquid crystal drive lens, VCM voice coil loudspeaker voice coil drive lens, MEMS to drive in lens, EDOF wave-front phase modulation lens or wafer scale microarray lens any one.Above-described liquid driven lens comprise fixed focus lenses, liquid lens, for controlling the voltage driver 111 of liquid lens; Above-described liquid crystal drive lens comprise fixed focus lenses, liquid crystal lens, for controlling the voltage driver 111 of liquid crystal lens; Above-described liquid driven lens and liquid crystal drive lens are regulated by the diopter that changes incident light both optical power to realize auto-focus function.Above-described VCM voice coil loudspeaker voice coil drives lens to comprise fixed focus lenses, VCM voice coil loudspeaker voice coil, for the current driver 111 of control VCM voice coil loudspeaker voice coil; Above-described VCM voice coil loudspeaker voice coil drives lens by Jiao after change optics both optical image apart from regulating to realize auto-focus function.Above-described MEMS (microelectromechanical systems) drives lens to comprise fixed focus lenses, MEMS lens, for the electrostatic actuator 111 of control MEMS lens.Above-described MEMS drives lens by changing the optical position of MEMS lens to realize auto-focus function.Above-described wafer scale array lenticule, is calculated to be picture (ComputationalImaging) by microlens array and realizes the dark Reconstruction of The Function of 3D panorama.Above-described EDOF wave-front phase modulation lens comprise lens, wave-front phase modulation optical element; Above-described EDOF wave-front phase modulation is by after the modulation of wave-front phase modulation optical element, and liftering demodulation is rebuild and realized extended depth-of-field function.

The specific embodiment of the invention 1 also comprises the OSI optical image stabilization driver to imaging system, the mobile vector information feed back optical image stabilization driver provided by transducers such as the gyroscopes that mobile terminal is integrated is fuzzy for the optical motion of control and compensation imaging system, can optimize the image quality effect of photo electric imaging system further.

Particularly, according to the gyroscope of the specific embodiment of the invention 1, the mobile vector information that the transducers such as linear velocity meter provide is fuzzy for the optical motion of feedback optical image stabilization driver OIS control and compensation imaging system, or for feeding back 3 axle mobile vector information, namely angular speed and/or linear velocity are less than predetermined threshold to control the optical motion of imaging system fuzzy, can optimize the image quality effect of photo electric imaging system further.

For removing the imaging interference of minute surface total reflection light, the LED illumination light source 106 of the specific embodiment of the invention 1 configures optical line polarizer, orthogonal state 90 degree optical line polarizers corresponding with (before or after being positioned at automatic focus optical imaging lens 102) configuration in imaging optical path, formed the linear polarization of orthogonal state by transmitting and receiving end, the imaging interference of minute surface total reflection light can be removed completely.Further, (before or after being positioned at automatic focus optical imaging lens 102) optical polarizator of tunable polarization state can be configured in imaging optical path, by controlling the polarization state of tunable optical polarizer, the imaging interference of minute surface total reflection light can be removed completely.

The specific embodiment of the invention 1, has different optical imaging requirements, imaging wavelength, pixel spatial resolution, optical magnification owing to bio-identification photoelectronic imaging and visible ray photoelectronic imaging, optical space resolution, focusing task object distance range.

Above-described bio-identification photoelectronic imaging has following optical imagery requirement:

The imaging wavelength WI of bio-identification photoelectronic imaging meets:

750nm≤WI≤950；

The focusing task object distance WD of bio-identification photoelectronic imaging meets:

10cm≤WD≤30cm。

The pixel spatial resolution PSR (pixelspatialresolution) of bio-identification photoelectronic imaging should meet: PSR >=10pixel/mm;

The optical magnification OM (opticalmagnification) of bio-identification photoelectronic imaging, should meet:

OM＝PS*PSR；

Wherein said: PS is the physical size of each imaging pixel cell of imageing sensor; PSR is the pixel spatial resolution of bio-identification photoelectronic imaging;

The optical space resolution OSRI (opticalspatialresolutionofimageofplane) of bio-identification photoelectronic imaging should meet in image space plane: when modulation transfer function equals 60% (MTF=0.6), 1/ (4*PS)≤OSRI≤1/ (2*PS) lp/mm (line is to every millimeter).

The optical imagery of the bio-identification photoelectronic imaging described in the specific embodiment of the invention 1 requires to realize high-resolution iris and the extraction of vein biometric characteristic details, improves combination bio-identification performance.

Described visible ray photoelectronic imaging has following optical imagery and requires:

The imaging wavelength WI of visible ray photoelectronic imaging meets:

400nm≤WI≤650nm；

The focusing task object distance WD of visible ray photoelectronic imaging meets:

30cm≤WD≤100cm。

The pixel spatial resolution PSR (pixelspatialresolution) of visible ray photoelectronic imaging should meet: PSR≤3pixel/mm;

The optical magnification OM (opticalmagnification) of visible ray photoelectronic imaging, should meet:

OM＝PS*PSR；

Wherein said: PS is the physical size of each imaging pixel cell of imageing sensor; PSR is the pixel spatial resolution of visible ray photoelectronic imaging;

The optical space resolution OSRI (opticalspatialresolutionofimageofplane) of visible ray photoelectronic imaging should meet in image space plane: when modulation transfer function equals 60% (MTF=0.6), 1/ (4*PS)≤OSRI≤1/ (2*PS) lp/mm (line is to every millimeter).

By above-described mobile terminal visible ray and bio-identification combination photoelectric imaging system, the present invention provides a kind of formation method of visible ray photoelectronic imaging, comprises the following steps:

1. processor chips 109 configure described optical filter, described LED illumination light source, described imageing sensor and described optical imaging lens is initial work state, particularly, namely carry out optical filter control and drive system 112, LED current driver 108, imageing sensor 105, automatic focus optical imaging lens focus driver 111 initial work state configures;

2. processor chips 109 control described optical filter, described LED illumination light source, described imageing sensor and described optical imaging lens and enter low-power consumption standby or shutdown mode, optical filter control and drive system 112, LED current driver 108, imageing sensor 105, automatic focus optical imaging lens focus driver 111 enters low-power consumption standby or shutdown mode;

3. processor chips judge whether to need to obtain visual light imaging image, are go to step 4, no continuation step 3;

4. processor chips 109 change visible ray-infrared light variable wavelength optics filter (101 or 104) for allowing by visual light imaging wavelength by optical filter control and drive system 112;

5. processor chips 109 control LED current driver 108 driving LED lighting source 106 and produce visual light imaging wavelength continuously or the radiation of lock-out pulse pattern;

6. the imaging array of processor chips 109 control chart image-position sensor 105 receives the original image RAWRGB pixel data I{Y} of overall frame imaging pattern or the output of rolling row imaging pattern;

7. processor chips 109 are according to imaging original image RAW pixel data I{Y} and pixel cell opto-electronic conversion relation, drive imageing sensor 105 and LED current driver 108 and automatic focus optical imaging lens focus driver 111, realize FEEDBACK CONTROL;

8. processor chips 109 are respectively to original image RAW pixel data I{Y} interpolation reconstruction and image procossing;

9. processor chips 109 export the image I{r after interpolated reconstruction and image procossing, g, b};

10. return step 2 to circulate.

In the step 7 of the formation method of the above visible ray photoelectronic imaging, FEEDBACK CONTROL comprises:

1. processor chips 109 can according to the imaging original image RAW pixel data I{Y} of imageing sensor 105 output and corresponding formula EQ1, the reset time of integration of FEEDBACK CONTROL imageing sensor 105, numeral and/or analog gain are arranged, the radiation intensity of FEEDBACK CONTROL LED current driver 108 driving LED lighting source 106, and radiated time is for improving image quality.

2. minute surface total reflection annoyance level in the processor chips 109 imaging original image RAW pixel data I{Y} computed image that can export according to imageing sensor 105, FEEDBACK CONTROL LED current driver 108 driving LED lighting source 106 is for controlling angle of radiation and position to improve image quality.

3. processor chips 109 can drive automatic focus optical imaging lens 102 to realize visible ray photoelectronic imaging focusing task object distance WD at least 30cm-100cm according to the focus mass value FEEDBACK CONTROL automatic focus optical imaging lens focus driver 111 calculating image original RAW pixel data I{Y}.Conventional known Atomatic focusing method can be adopted as fuzzy in focus quality peak-peak to accurate iterative search.

Processor chips 109 can pass through light sensor (according to situation about using, so independent additional device can be set in processor chips 109, its method arranged is present known technology, or such light sensor function can also be realized by commercially purchasing corresponding processor chips) according to current environmental light brightness, control the radiation intensity of LED current driver 108 driving LED lighting source 106 visible ray.Further, if when the specific embodiment of the invention 1 light sensor judges to be greater than more than 500-1000lux according to current environmental light brightness, close LED current driver drives LED illumination light source 106 visible ray.

Further explain, the interpolated reconstruction described in the step 8 of the formation method of the above visible ray photoelectronic imaging can adopt conventional known interpolation algorithm.

Image procossing described in the step 8 of the formation method of visible ray photoelectronic imaging comprises imagery optical black-level correction BLC, Automatic white balance AWB, color matrices corrects CCM, rims of the lens shadow correction lensshadingcorrection, automatic exposure FEEDBACK CONTROL AEC, automatic gain FEEDBACK CONTROL AGC etc.

By above-described mobile terminal visible ray and bio-identification combination photoelectric imaging system, the present invention provides a kind of formation method of bio-identification photoelectronic imaging, comprises the following steps:

1. processor chips 109 configure described optical filter, described LED illumination light source, described imageing sensor and described optical imaging lens is initial work state, particularly, namely carry out optical filter control and drive system 112, LED current driver 108, imageing sensor 105, automatic focus optical imaging lens focus driver 111 initial work state configures;

2. processor chips 109 control described optical filter, described LED illumination light source, described imageing sensor and described optical imaging lens and enter low-power consumption standby or shutdown mode, particularly, i.e. optical filter control and drive system 112, LED current driver 108, imageing sensor 105, automatic focus optical imaging lens focus driver 111 enters low-power consumption standby or shutdown mode;

3. processor chips judge whether to need to obtain bio-imaging image, are go to step 4, no continuation step 3;

4. processor chips 109 change visible ray-infrared light variable wavelength optics filter (101 or 104) for allowing by near infrared imaging wavelength by optical filter control and drive system 112;

5. processor chips 109 control LED current driver 108 driving LED lighting source 106 and produce near infrared imaging wavelength continuously or the radiation of lock-out pulse pattern;

6. the imaging array of processor chips 109 control chart image-position sensor 105 receives the original image RAWRGB pixel data I{Y} of overall frame imaging pattern or the output of rolling row imaging pattern;

7. processor chips 109 are according to imaging original image RAW pixel data I{Y} and pixel cell opto-electronic conversion relation, drive imageing sensor 105 and LED current driver 108 and automatic focus optical imaging lens focus driver 111, realize FEEDBACK CONTROL;

8. processor chips 109 output image I{Y};

9. return step 2 to circulate.

In the specific embodiment of the invention 1 step 1, imageing sensor 105 initial work state is configured to RAWRGB pixel output format, and the gain of RGB channel compensation or RGB channel balance gain process arrange corresponding RGB passage numeral and/or the analog gain simple implementation of imageing sensor 105 by the configuration of initial work state.Further image imaging sensor 105, forbidding color matrices corrects CCM, forbidding interpolation interpolation, forbidding Gamma corrects, and forbidding Automatic white balance AWB, uses these functions to cause biological image contrast to reduce, special texture high frequency edge part, affects biometric image quality.

In the step 7 of the formation method of the above bio-identification photoelectronic imaging, FEEDBACK CONTROL comprises:

1. processor chips 109 can according to the imaging original image RAW pixel data I{Y} of imageing sensor 105 output and corresponding formula EQ1, the reset time of integration of FEEDBACK CONTROL imageing sensor 105, numeral and/or analog gain are arranged, the radiation intensity of FEEDBACK CONTROL LED current driver 108 driving LED lighting source 106, and radiated time, for control chart image brightness, signal to noise ratio and motion blur degree improve image quality.

2. minute surface total reflection annoyance level and contrast lightness balanced intensity in the processor chips 109 imaging original image RAW pixel data I{Y} computed image that can export according to imageing sensor 105, FEEDBACK CONTROL LED current driver 108 driving LED lighting source 106 is for controlling angle of radiation and position to improve image quality.

3. processor chips 109 can drive automatic focus optical imaging lens 102 to realize bio-identification photoelectronic imaging focusing task object distance WD at least 10cm-30cm according to the focus mass value FEEDBACK CONTROL automatic focus optical imaging lens focus driver 111 calculating image original RAW pixel data I{Y}.Conventional known Atomatic focusing method can be adopted as fuzzy in focus quality peak-peak to accurate iterative search.

Further, the original RAW pixel data of the image that processor chips 109 can be exported by imageing sensor 105, the optical black level of carries out image transducer corrects BLC, automatic exposure FEEDBACK CONTROL AEC, automatic gain FEEDBACK CONTROL AGC.

Consider bio-identification focusing requirement, high pixel spatial resolution, large optical magnification, the focusing task object distance range of microspur, conventional known Atomatic focusing method is as fuzzy in focus quality peak-peak needs the 1s time more than to accurate iterative search.

For realizing the fast and stable automatic focus in 100ms, the specific embodiment of the invention 1, by above-described mobile terminal visible ray and bio-identification combination photoelectric imaging system, provides one and provides a kind of fast automatic focusing method, comprise the following steps:

1., according to predetermined focusing task object distance range WD, define local region of interest ROI to be searched and search parameter;

Define local region of interest ROI to be searched to be determined by following formula;

1/EFL＝1/ROI+1/WD；

Wherein: described EFL is automatic focus optical imaging lens fixed focal length;

WD is predetermined biological focusing task object distance range, 10-30cm;

ROI is local region of interest scope to be searched accordingly;

Definition search parameter comprises:

Step-size in search SStep and searching times SNO can be determined by following formula:

SStep＝k*PS；

SNO＝ROI/SStep；

Wherein: described PS is the physical size of the imaging pixel cell of imageing sensor 105;

K is the acceptable circle of confusion diameter dimension of biological recognizer;

2. processor chips 109 control automatic focus optical imaging lens focus driver 111 according to defining local region of interest ROI to be searched and search parameter in step 1, drive automatic focus optical imaging lens 102 to perform and search in continuity from above focal position, dull direction.Namely perform in { Pi, i=1, the SNO} search of continuity from above focal position, dull direction;

The search of dull continuity focal position, direction, can avoid adopting that conventional known Atomatic focusing method is as fuzzy in focus quality peak-peak causes both forward and reverse directions repeatedly to accurate iterative search, and have efficient, stablize, focusing speed is fast.

3. in processor chips 109 control chart image-position sensor 105 obtaining step 2, in continuity from above focal position, dull direction, { Pi, i=1, SNO} search for the imaging original image RAWRGB pixel data I{Pi exported, i=1, NO};

4. processor 109 chip calculates focal position searching image I{Pi in real time, the focus quality Q S (I{Pi}) of i=1, NO}; Described function QS is focus quality evaluation functions, and the method that described focus quality evaluation functions adopts comprises: gradient is added up, frequency statistics, high pass or the logical spatial filter of band, high-frequency energy Data-Statistics, variance statistic, the methods such as space-frequency domain filter; Focus quality evaluation functions QS of the present invention is not limited to above-mentioned citing, and additive method should by equivalent understanding.

5. processor 109 judges pinpointed focus quality arg{QS (I{Pi}) } corresponding image is optimum focusing image;

Arg{QS (I{Pi}) }=max{QS (I{Pi}) } corresponding focus quality maximum image is optimum focusing image;

Further,

Arg{QS (I{Pi}) }=focus quality maximum image that { QS (I{Pi-1}) <QS (I{Pi}) >QS (I{Pi+1}) } is corresponding is optimum focusing image;

Also can adopt

Arg{QS (I{Pi}) }=focus quality image that { QS (I{Pi}) >EI) } is corresponding is optimum focusing image;

EI is the acceptable image focal point quality threshold of biological recognizer.

Judgement focus quality method of the present invention is not limited to above-mentioned citing, and additive method should by equivalent understanding.

The invention provides a kind of false proof divine force that created the universe biopsy method of bio-identification of high security, have, to bio-identification counterfeit, there is real-time detectability, for ensureing the fail safe of bio-identification itself, in the following ways:

By biological tissue's enhanced spectrometry-active characteristic real-time detection method that visible ray-near infrared imaging wavelength radiation produces.

By above-described mobile terminal visible ray and bio-identification combination photoelectric imaging system, the present invention provides biological tissue's enhanced spectrometry-active characteristic real-time detection method that a kind of visible ray-near infrared imaging wavelength radiation produces, and comprises the following steps:

1. processor chips 109 change visible ray-infrared light variable wavelength optics filter (101 or 104) by optical filter control and drive system 112 is visual light imaging wavelength;

Processor chips 109 drived control LED current driver 108 driving LED lighting source 106 produces visual light imaging wavelength radiation;

Processor chips 109 obtain the visual light imaging wavelength graph of imageing sensor 105 imaging array as Ivs;

2. processor chips 109 change visible ray-infrared light variable wavelength optics filter (101 or 104) by optical filter control and drive system 112 is near infrared imaging wavelength;

Processor chips 109 drived control LED current driver 108 driving LED lighting source 106 produces near infrared imaging wavelength radiation;

Processor chips 109 obtain the near infrared imaging wavelength graph of imageing sensor 105 imaging array as Iir;

3. processor chips 109 calculation procedure 1, in 2, visual light imaging wavelength graph is as Ivs and near infrared imaging wavelength graph as the contrast C data of Iir, is respectively Ivs_C, and Iir_C;

Wherein:

C is the contrast between iris region and iris exterior domain;

Or

C is the contrast between venosomes and vein exterior domain;

C＝S(Yiris)/S(Youtiris)；

Or

C＝S(Youtvein)/S(Yvein)；

Yiris represents iris region pixel;

Youtiris represents iris exterior domain pixel;

Yvein represents venosomes pixel;

Youtvein represents vein exterior domain pixel;

Described function S is respective regions pixels statistics valuation functions, and the method that described pixels statistics valuation functions adopts comprises: statistics with histogram, frequency statistics, and mean value is added up, weighted average Data-Statistics, middle Data-Statistics, energy value is added up, variance statistic, gradient is added up, space-frequency domain filter etc.; Respective regions pixels statistics valuation functions S of the present invention is not limited to above-mentioned citing, and additive method should by equivalent understanding.

4. processor chips 109 calculate picture contrast Ivs_C and the Iir_C activity change rate Δ ρ of visual light imaging wavelength radiation and near infrared imaging wavelength radiation respectively in real time;

Wherein:

Δρ＝Iir_C/Ivs_C*100％；

5. according to visible ray-near infrared imaging wavelength radiation biological tissue enhanced spectrometry-active characteristic preset value, with the active contrast respective change rate of data value Δ ρ in step 4, Rule of judgment Δ ρ > 300% realizes detecting biological living state in real time.

Equivalent understanding, the step 1 in biological tissue's enhanced spectrometry-active characteristic real-time detection method that above-mentioned visible ray-near infrared imaging wavelength radiation produces and 2 orders have equivalence, can exchange.

For realizing improving bio-identification success rate, the specific embodiment of the invention 1 (according to mobile terminal visible ray and bio-identification combination photoelectric imaging system) provides a kind of formation method for improving bio-identification success rate, comprises the following steps:

1. during registration, gather the near infrared imaging wavelength biometric image Iir{P ψ enroll} that at least two or more LED illumination light source 106 produces when different angle of radiation and position;

The specific embodiment of the invention 1 is illustrated and is adopted different angle of radiation and position citing as left side Pl, right side Pr, left and right sides Pl & Pr, upside Pt, downside Pb, upper and lower both sides Pt & Pb, in [5-30] angle of radiation, any one or multiple angles are as 5 degree, 10 degree, 20 degree, 30 degree).

2. use biometric image Iir{P ψ enroll} to calculate and obtain at least two or more biometric templates Template{P ψ enroll}, carry out intersecting between feature templates after comparison success, save as the biometric templates of registration;

Described intersection comparison citing, as obtained 3 biometric templates Template{1,2,3} carries out intersection comparison and is respectively Template1-Template2, Template1-Template3, Template2-Template3; Only have and to intersect after comparison success when between above-mentioned feature templates, guarantee is used for stability and the discrimination of the biometric templates of the registration of follow-up identification.

3. the near infrared imaging wavelength biometric image Iir{P ψ recogn} that the LED illumination light source 106 gathering or more when identifying produces when different angle of radiation and position;

4. use one or more biometric image Iir{P ψ recogn} to calculate between the feature templates Template{P ψ recogn} of generation with the biometric templates Template{P ψ enroll} of registration to carry out intersecting comparison and obtaining recognition result;

For realizing improving bio-identification success rate, the specific embodiment of the invention 1 (according to mobile terminal visible ray and bio-identification combination photoelectric imaging system) reoffers another for improving the formation method of bio-identification success rate, comprises the following steps:

1. the near infrared imaging wavelength biometric image Iir{Renroll} that during registration, the LED illumination light source 106 of collection at least two kinds or more produces when different radiation intensity;

The specific embodiment of the invention 1 is illustrated and is adopted different visible light and infrared light radiation intensity generation biological tissue such as pupil to stimulate

Active near infrared imaging wavelength biometric image, as produced 1 times, 2 times, the different visible light of 4 times or more and/or infrared light radiation intensity;

2. use biometric image Iir{Renroll} to calculate and obtain at least two or more biometric templates Template{Renroll}, carry out intersecting between feature templates after comparison success, save as the biometric templates of registration;

Described intersection comparison citing, as obtained 3 biometric templates Template{1,2,3} carries out intersection comparison and is respectively Template1-Template2, Template1-Template3, Template2-Template3; Only have and to intersect after comparison success when between above-mentioned feature templates, guarantee is used for stability and the discrimination of the biometric templates of the registration of follow-up identification.

3. the near infrared imaging wavelength biometric image Iir{Rrecogn} that the LED illumination light source 106 gathering or more when identifying produces when different radiation intensity;

4. use one or more biometric image Iir{Rrecogn} to calculate between the feature templates Template{Rrecogn} of generation with the biometric templates Template{Renroll} of registration to carry out intersecting comparison and obtaining recognition result;

For realizing improving bio-identification success rate, the specific embodiment of the invention 1 (according to mobile terminal visible ray and bio-identification combination photoelectric imaging system) also provides another for improving the formation method of bio-identification success rate again, comprises the following steps:

1. the near infrared imaging wavelength biometric image Iir{Wenroll} that during registration, the LED illumination light source 106 of collection at least two kinds or more produces when different radiated wavelength range;

The specific embodiment of the invention 1 citing adopts LED illumination light source 106 to produce the near infrared imaging wavelength biometric image of different radiated wavelength range, citing is as produced 750nm-800nm respectively, 800nm-850nm, 850nm-900nm, 900nm-950nm, the different radiated wavelength range such as 750nm-850nm, 850nm-950nm or combination.

2. use biometric image Iir{Wenroll} to calculate and obtain at least two or more biometric templates Template{Wenroll}, carry out intersecting between feature templates after comparison success, save as the biometric templates of registration;

Described intersection comparison citing, as obtained 3 biometric templates Template{1,2,3} carries out intersection comparison and is respectively Template1-Template2, Template1-Template3, Template2-Template3; Only have and to intersect after comparison success when between above-mentioned feature templates, guarantee is used for stability and the discrimination of the biometric templates of the registration of follow-up identification.

3. the near infrared imaging wavelength biometric image Iir{Wrecogn} that the LED illumination light source 106 gathering or more when identifying produces when different radiated wavelength range;

4. use one or more biometric image Iir{Wrecogn} to calculate between the feature templates Template{Wrecogn} of generation with the biometric templates Template{Wenroll} of registration to carry out intersecting comparison and obtaining recognition result;

The specific embodiment content that the present invention describes and technical characteristic, can be implemented in the scope of identical or equivalent understanding, as imaging wavelength range change, imageing sensor changes, LED illumination light source changes, and optical filter changes, and automatic focus optical imaging lens changes, light chopper, device substitutes also should by equivalent understanding.

As an example, the LED illumination light source visible long-wave radiation of the specific embodiment that the present invention describes, the display screen that mobile terminal self also can be utilized to possess replaces, and as LCD display has the RGB back light of brightness-adjustable, or self has the organic substance illuminating OLED of RGB radiation.

Further illustrate, optical filter control and drive system substitutes as manual switch is equivalent by installing hand controller.

Finally, it is also to be noted that what enumerate above is only several specific embodiments of the present invention.Obviously, the invention is not restricted to above embodiment, many distortion can also be had.All distortion that those of ordinary skill in the art can directly derive from content disclosed by the invention or associate, all should think protection scope of the present invention.

Claims (9)

1., for a driving auto focusing method for living things feature recognition mobile terminal, comprise the following steps:

1) according to predetermined focusing task object distance range, local region of interest to be searched and search parameter is defined;

2) control both optical imaging len is according to step 1) in definition local region of interest to be searched and search parameter, drive automatic focus optical imaging lens to perform and search in continuity from above focal position, dull direction;

3) control chart image-position sensor obtaining step 2) in continuity from above focal position, dull direction search export imaging image pixel data;

4) calculate focal position searching image I{Pi in real time, the focus quality of i=1, NO}, and assess focus quality;

5) judge that image corresponding to pinpointed focus quality is optimum focusing image.

2. drive auto focusing method as claimed in claim 1, wherein said step 1) in definition local region of interest ROI to be searched determined by following formula;

1/EFL＝1/ROI+1/WD；

Wherein: described EFL is automatic focus optical imaging lens fixed focal length;

WD is predetermined biological focusing task object distance range;

ROI is local region of interest scope to be searched accordingly.

3. drive auto focusing method as claimed in claim 2, wherein said predetermined biological focusing task object distance range is 10-30cm.

4. drive auto focusing method as claimed in claim 1, wherein said step 2) in described search parameter comprise step-size in search SStep and searching times SNO, determined by following formula:

SStep＝k*PS；

SNO＝ROI/SStep；

Wherein: described PS is the physical size of the imaging pixel cell of imageing sensor;

K is the acceptable circle of confusion diameter dimension of biological recognizer;

ROI is local region of interest scope to be searched accordingly.

5. drive auto focusing method as claimed in claim 1, wherein said step 4) described in the valuation functions QS of focus quality be selected from least one in following method: gradient is added up, frequency statistics, high pass or the logical spatial filter of band, high-frequency energy Data-Statistics, variance statistic, space-frequency domain filter.

6. drive auto focusing method as claimed in claim 1, wherein said step 5) judge that the method for pinpointed focus quality is: arg{QS (I{Pi}) }=max{QS (I{Pi}) } corresponding focus quality maximum image is optimum focusing image, wherein said QS is the valuation functions of focus quality.

7. drive auto focusing method as claimed in claim 1, wherein said step 5) judge that the method for pinpointed focus quality is: arg{QS (I{Pi}) }=focus quality maximum image that { QS (I{Pi-1}) <QS (I{Pi}) >QS (I{Pi+1}) } is corresponding is optimum focusing image, wherein said QS is the valuation functions of focus quality.

8. drive auto focusing method as claimed in claim 1, wherein said step 5) judge that the method for pinpointed focus quality is: arg{QS (I{Pi}) }=focus quality image that { QS (I{Pi}) >EI) } is corresponding is optimum focusing image, wherein said QS is the valuation functions of focus quality, and EI is the acceptable image focal point quality threshold of biological recognizer.

9. for a mobile terminal for living things feature recognition, described mobile terminal comprises optical imaging lens and imageing sensor, it is characterized in that: the method applied as described in any one in claim 1-8 carries out driving automatic focus.