Face and iris imaging system and method
A duplex camera with common face and iris imaging optics locates an iris in a scene and images the iris without requiring multiple camera alignment or a rapid zoom capability. A wavelength selective mirror separates the light from an imaged scene into visible and infrared components. The visible component supplies a face image in which an iris location can be determined. Visible light optics and a visible light sensor array provide a scene image to an image processor that determines the iris location. Infrared optics and an infrared sensor produce an iris image centered on the iris location. Upon determining an iris location, a motorized stage can position the iris image in the infrared sensor. The common face and imaging optics allow the image sensors to be permanently aligned to one another.
1. A face and iris imaging system comprising:
an imaging port that accepts a light input comprising an infrared component and a visible component wherein the light input is produced by a scene wherein the scene comprises a face comprising at least one eye comprising an iris;
a wavelength selective mirror that directs the visible component along a first optical path and directs the infrared component along a second optical path;
an IR optics module and an IR sensor array positioned on the second optical path wherein the IR sensor array produces an IR image with a centered said iris;
a visible light optics module and a visible light sensor positioned on the first optical path wherein the visible light sensor produces a visible light image that comprises a face image comprising at least one eye image; and
an image processing module that analyzes both the visible light image and IR image to determine an iris location from the visible light image and isolate an iris image from the IR image to recognize and identify a person based on characteristics of said iris.
2. The system of claim 1 further comprising an IR flash illuminator wherein the production of the IR image is synchronized to the production of an IR flash.
3. The system of claim 1 further comprising a driven stage wherein the driven stage redirects the second optical path to position the iris image on the IR sensor array.
4. The system of claim 1 :
wherein the visible light optics module includes a first driven focuser;
wherein the IR lens module comprises a second driven focuser; and
wherein an auto focus module controls the first driven focuser and also controls the second driven focuser.
5. An iris imaging system comprising:
an imaging port that accepts a light input comprising an infrared component and a visible component wherein the light input is produced by a scene;
a wavelength selective mirror that directs the visible component along a first optical path and directs the infrared component along a second optical path;
a visible light sensor positioned on the first optical path wherein the visible light sensor produces a visible light image;
an image distance separator positioned on the second optical path that separates a first infrared component and a second infrared component from the infrared component wherein the infrared component carries an infrared image, wherein the first infrared component carries a first subimage, wherein the second infrared component carries a second subimage, and wherein the first subimage and the second subimage are different areas of the infrared image;
an infrared sensor positioned to receive the first infrared component and the second infrared component to thereby produce a two-part infrared image; and
an iris location determined from the visible light image and an iris image obtained from the two-part infrared image to recognize and identify a person based on characteristics of said iris.
6. The system of claim 5 :
wherein the visible light image comprises a face image comprising a first eye image and a second eye image;
wherein the first eye image comprises a first iris image and wherein the second eye image comprises a second iris image;
wherein an iris separation distance is determined from the face image, wherein the iris separation distance is the distance between the first iris and the second iris; and
wherein the image distance separator is a driven image distance separator that adjusts the separation of the first infrared component and the second infrared component to compensate for the iris separation distance.
7. The system of claim 5 further comprising an IR flash illuminator wherein the production of the IR image is synchronized to the production of an IR flash.
8. The system of claim 5 further comprising a driven stage wherein the driven stage redirects the first optical path, or redirects the second optical path and wherein “or” is inclusive.
9. The system of claim 5 :
wherein the visible light image comprises a face image comprising at least one eye image; and
wherein an iris location is determined from the face image and isolates an iris image from the IR image.
10. The system of claim 5 further comprising a driven stage wherein the iris image is positioned on the IR sensor array by moving the driven stage based on the iris location.
11. The system of claim 5 further comprising:
an IR flash illuminator wherein the production of the IR image is synchronized to the production of an IR flash;
an image processing module, a motion control module, and a driven stage;
wherein the visible light image comprises a face image comprising a first eye image and a second eye image;
wherein the first eye image comprises a first iris image and wherein the second eye image comprises a second iris image;
wherein the image processing module determines an iris separation from the face image, wherein the iris separation is the distance between the first iris and the second iris;
wherein the image distance separator is a driven image distance separator that adjusts the separation of the first infrared component and the second infrared component to compensate for the iris separation;
wherein the driven stage positions at least one iris image on the IR sensor array;
wherein the visible light optics module comprises a first driven focuser;
wherein the IR lens module comprises a second driven focuser; and
wherein an auto focus module controls the first driven focuser and also controls the second driven focuser.
12. The system of claim 5 further comprising:
an image processing module, a motion control module, a driven stage, and a steered collimated IR light source;
wherein the visible light image comprises a face image including a first eye image and a second eye image;
wherein the first eye image comprises a first iris image and wherein the second eye image comprises a second iris image;
wherein the image processing module determines an iris separation from the face image, wherein the iris separation is the distance between the first iris and the second iris;
wherein the image processing module determines at least one iris location from the face image;
wherein the image distance separator is a driven image distance separator that adjusts the separation of the first infrared component and the second infrared component to compensate for the iris separation;
wherein the driven stage positions at least one iris image on the IR sensor array;
wherein the visible light optics module comprises a first driven focuser;
wherein the IR lens module comprises a second driven focuser;
wherein an auto focus module controls the first driven focuser and also controls the second driven focuser; and
wherein the steered collimated IR light source is automatically steered based on the at least one iris location before the IR image is produced.
13. An iris imaging method comprising:
obtaining a light input from an imaged scene comprising a face;
splitting the light input into a visible light component and an infrared light component;
producing a visible light image comprising a face image wherein the face image comprises a first eye image and a second eye image eye image;
adjusting the infrared light component to isolate and magnify a first iris subimage and a second iris subimage onto an infrared imaging sensor;
producing an infrared image comprising the first iris subimage and the second iris subimage; and
analyzing both the visible light image and the infrared image to determine a first iris location and a second iris location from the visible light and isolating an iris image from the first iris subimage and the second iris subimage to recognize and identify a person based on characteristics of said iris.
14. The method of claim 13 further comprising producing an infrared light flash wherein the production of the infrared light flash and the production of the infrared image are synchronized.
15. The method of claim 13 further comprising illuminating the imaged scene with a collimated infrared light source that is steered to point at the iris location after the iris location is determined and before the IR image is produced.
16. The method of claim 13 further comprising:
determining the location of the face; and
aiming a collimated infrared light source at the face before producing the infrared image.
17. The method of claim 16 further comprising producing an infrared light flash from the collimated infrared light source wherein the production of the infrared light flash and the production of the infrared image are synchronized.