Method and apparatus for iris recognition
View Patent ↗The invention relates to an iris recognition method, comprising the steps of acquiring an image of at least one eye of a user in an infrared spectrum, and of processing said image to extract therefrom identification characteristics from the iris as defined by an outer boundary in the eye, the method comprising the steps of: acquiring an image of the eye in a visible spectrum substantially simultaneously with acquiring the image of the eye in the infrared spectrum; and prior to processing the infrared image, determining the outer boundary of the iris from the image in the visible spectrum. The invention also provides iris recognition apparatus.
1. An iris recognition method, comprising the steps of:
acquiring an image of at least one eye of a user in an infrared spectrum in an image sensor;
processing said image to extract therefrom identification characteristics from the iris as defined by an outer boundary in the eye;
acquiring an image of the eye in a visible spectrum in the image sensor substantially simultaneously with acquiring the image of the eye in the infrared spectrum; and
prior to processing the infrared image, determining the outer boundary of the iris from the image in the visible spectrum.
2. A method according to claim 1 , further comprising the step of extracting at least one colorimetric characteristic of the image in the visible spectrum.
3. A method according to claim 2 , wherein the colorimetric characteristic is a spectral distribution.
4. A method according to claim 2 , wherein the identification characteristics are compared with iris identification characteristics stored in a database that also contains colorimetric characteristics, and wherein the extracted colorimetric characteristic is used to sort the database prior to comparing the identification characteristics.
5. Iris recognition apparatus for implementing the method of:
acquiring an image of at least one eye of a user in an infrared spectrum;
processing said image to extract therefrom identification characteristics from the iris as defined by an outer boundary in the eye;
acquiring an image of the eye in a visible spectrum substantially simultaneously with acquiring the image of the eye in the infrared spectrum; and
prior to processing the infrared image, determining the outer boundary of the iris from the image in the visible spectrum;
the apparatus comprising:
a first image acquisition device which acquires an image of the eye in the infrared spectrum; and, a second image acquisition device which acquires an image of the eye in a visible spectrum.
6. Apparatus according to claim 5 , wherein said first image acquisition device includes a sensor having spectral sensitivity in the infrared and said second image acquisition device includes at least one sensor having spectral sensitivity in the visible.
7. Apparatus according to claim 6 , wherein said second image acquisition device includes a sensor having spectral sensitivity in the red and a sensor having spectral sensitivity in the blue and the green.
8. Apparatus according to claim 5 , wherein a sensor having spectral sensitivity covering both the visible and the near infrared is used in both the image acquisition devices.
9. Apparatus according to claim 5 , wherein each acquisition device includes a filter.