Summary of the invention
To solve the above problems, the device is by optical coherence it is an object of the present invention to provide a kind of iris imaging deviceChromatography imaging technique is to obtain the high-definition picture of iris tissue, and the conduct simultaneously of the vascular distribution of available iris regionUp to 99% recognition accuracy may be implemented to improve recognition accuracy in identification feature.
In order to reach above-mentioned technical purpose, technical scheme is as follows: a kind of iris imaging device, including light source,Circulator, fiber coupler, sample arm, reference arm, spectrometer and processor, wherein it is saturating that the first collimation is equipped in reference armMirror, the first lens and stationary mirror, are equipped with the second collimation lens in sample arm, quick scanning galvanometer, slow scanning galvanometer, theTwo lens；Spectrometer includes third collimation lens, grating, the third lens, linear camera,
The light that light source issues is led through circulator back into optical coupler, splits the light into two beams, a branch of arrival reference arm,A branch of arrival sample arm is scanned sample, and the light into reference arm focuses on admittedly after the first collimation lens and the first lensDetermine reflecting mirror, then returns；Into the light of sample arm, after the second collimation lens, successively by quick scanning galvanometer and slowlyThen fast scanning galvanometer is scanned through the second lens focus to eyeground；The light that two-arm returns occurs after entering fiber couplerThen interference is received by circulator guiding by spectrometer, first by after third collimation lens collimation, through raster beam-splitting, then pass throughThe third lens focus on linear camera, and linear camera is received by wavelength light splitting and carries sample depth informative spectral, at processorIt is imaged after reason.
The iris imaging device obtains the high-definition picture of iris tissue by Optical Coherence Tomography Imaging Technology,The drawbacks of to avoid traditional cameras.
Further, the light source is the Low coherence wideband light source that center wavelength is 800nm-1350nm, to guarantee to differentiateRate.
Further, the fiber coupler is 2 × 2 fiber couplers.
Further, it is additionally provided with polarizer in the sample arm, be located in front of the second collimation lens, to be adjusted into sampleThe polarization state of arm light, so that imaging is more stable.
Another aspect of the present invention additionally provides a kind of iris identification method, includes the following steps:
Step 1) obtains iris 3-D image using above-mentioned iris imaging device；
Step 2), image optimization and noise reduction process reduce image artifacts；
Step 3) extracts iris surface texture and vascular morphology distribution is special by iris 3-D image after normalizationSign, and matching comparison is carried out with sample message, finally identify identity.
Another aspect of the invention additionally provides a kind of iris identification equipment, including
Above-mentioned iris imaging device, for obtaining iris 3-D image；
Memory, for storing iris sample information；
Processor, the iris image obtained for handling the iris imaging device；And it is taken out from the iris image of acquisitionIris surface texture and vascular morphology distribution characteristics are taken, match comparing with the iris sample information in the memory.
Iris imaging device of the invention realizes iris surface texture and vascular morphology by means of optical coherence tomographyThe high-precision of distribution is imaged.Recognition methods of the invention combines its iris imaging device, while extracting the iris obtained in imageSurface texture and its vascular morphology are distributed while being used as identification feature, and the iris that high-precision high-accuracy (99%) may be implemented is knownNot.
Specific embodiment
The technical solution that the present invention will be described in detail in the following with reference to the drawings and specific embodiments.
As shown in Figure 1, the iris imaging device of one embodiment of the invention, including light source 1, circulator 2, fiber coupler3, reference arm 4, sample arm 5, spectrometer 6 and processor 7, wherein the first collimation lens 4-1, first are equipped in reference arm 4 thoroughlyMirror 4-2 and stationary mirror 4-3, sample arm 5 is interior to be equipped in the second collimation lens 5-1, quick scanning galvanometer 5-2, slow scanningGalvanometer 5-3, the second lens 5-4；Spectrometer 6 includes third collimation lens 6-1, grating 6-2, the third lens 6-3, linear camera 6-4。
Light source 1 is the Low coherence wideband light source that center wavelength is 800nm-1350nm, to guarantee resolution ratio, such as 800nm,850nm, 900nm, 950nm, 1000nm, 1150nm, 1210nm, 1310nm, 1350nm etc..Fiber coupler 3 is 2 × 2 optical fiberCoupler.In order to be adjusted into the polarization state of 4 light of sample arm, so that imaging is more stable, polarizer 4- is additionally provided in sample arm 45, it is located in front of the second collimation lens 4-1.
The light that light source 1 issues is led through circulator 2 back into optical coupler 3, and two beams, a branch of arrival reference are splitted the light intoArm 4, a branch of arrival sample arm 5 are scanned sample, into reference arm 4 light through the first collimation lens 4-1 and the first lensStationary mirror 4-3 is focused on after 4-2, is then returned；Into the light of sample arm 5, after polarizer 4-5 filtering, the is passed throughTwo collimation lens 4-1, then in turn through quick scanning galvanometer 4-2 and slow scanning galvanometer 4-3, then through the second lens 4-4Eyeground is focused on to be scanned；The light that two-arm returns interferes after entering fiber coupler 3, is then oriented to by circulator 2It is received by spectrometer 6, into after spectrometer, is first collimated through third collimation lens 6-1, then through grating 6-2 beam splitting, most afterwards through theThe poly- 6-3 coke of three lens is received by wavelength light splitting to linear camera 6-4, linear camera 6-4 and carries sample depth informative spectral, processingAfter be imaged.
The iris imaging device, by Optical Coherence Tomography Imaging Technology, using Michelson's interferometer principle, to obtainThe high-definition picture of iris tissue, axial resolution can achieve 1-10 μm, and radial resolving power is at 1-10 μm.
In view of iris imaging device of the invention not only can be to iris iris texture form, can also be to iris vesselsDeng progress high-resolution imaging, therefore the present invention also provides a kind of iris identification methods, as Figure 2-3, include the following steps:
Step S01 obtains iris 3-D image, as shown in Figure 3b using above-mentioned iris imaging device.
The two dimension combined due to iris imaging device provided by the invention using fast scan galvanometer and slow scanning galvanometerScanning galvanometer system can carry out three-dimensional imaging to iris, obtain depth information etc., so as to preferably extract iris biologyFeature.
Step S02, image optimization and noise reduction process reduce image artifacts.
Fig. 3 c is image after optimization processing, by comparison diagram 3b and Fig. 3 c, it is not difficult to find out that, by image procossing,It can preferably eliminate the false and retain the true, convenient for extracting effective information.
Step S03 extracts iris surface texture and vascular morphology distribution is special by iris 3-D image after normalizationSign, and matching comparison is carried out with sample message, finally identify identity.
Image after optimization processing is passed through into normalized, iris surface texture can be extracted and vascular morphology distribution is specialSign, is then based on both features, match comparing with stored sample message, to identify identity.The recognition methods,Iris surface texture is combined with the distribution of its vascular morphology, up to 99% high-precision high-accuracy identification may be implemented.
In addition, a kind of iris identification equipment is additionally provided based on iris imaging device of the invention, as shown in figure 4, including
Above-mentioned iris imaging device, for obtaining iris 3-D image；
Memory can be computer CPU etc. for storing iris sample information；
Processor, the iris image obtained for handling the iris imaging device；And it is taken out from the iris image of acquisitionIris surface texture and vascular morphology distribution characteristics are taken, match comparing with the iris sample information in memory, it such as can be withIt is common arm processor etc..
Specifically, as shown in figure 5, the structure chart of the iris identification equipment for a specific embodiment of the invention, moves bottomSeat 1, lifting support 2, head fixing device 3, iris imaging device 4, computer 5, lifting support 2 are fixedly installed in removable bottomSeat 1 on, head fixing device 3 is fixed on lifting support 2, and be located at iris imaging device 4 front, iris imaging device withComputer 5 couples, and is provided with processor and memory in computer 5.
When carrying out iris recognition using the equipment of the embodiment, process as shown in fig. 6, first by adjusting lifting support 2,Head is fixed in measurement fixed point by head fixing device 3, then iris imaging device 4 carries out iris imaging, Jin ErjiCalculation machine 5 identifies iris structure image and blood-stream image, obtains relevant information, and respectively from structural texture with the mould of known as memoryPlate compares, and compares from vascular distribution with the template of known as memory, matches by judgement, final output matching letterBreath.
For realize iris recognition, the solution of the present invention abandoning tradition using high definition camera obtain iris image method,It selects to use Optical Coherence Tomography Imaging Technology to obtain the high-definition picture of iris tissue, not only the line of available irisInformation is managed, the high definition vascular distribution information of iris region can also be obtained, is fixed in this way in identification in existing selection irisOn the basis of zone-texture is as identification feature, while the vascular distribution that can add iris region is identification feature to be knownNot, so that recognition methods accuracy rate of the invention improves, up to 99%.
According to the disclosure and teachings of the above specification, those skilled in the art in the invention can also be to above-mentioned embodiment partyFormula is changed and is modified.Therefore, the invention is not limited to the specific embodiments disclosed and described above, to of the inventionSome modifications and changes should also be as falling into the scope of the claims of the present invention.In addition, although being used in this specificationSome specific terms, these terms are merely for convenience of description, does not limit the present invention in any way.