Iris imaging apparatus and methods for configuring an iris imaging apparatus

摘要

The invention comprises an iris imaging apparatus comprising an image sensor and an optical assembly. The optical assembly comprises an image-side surface and an object-side surface. The optical imaging lens assembly may be configured such that D1≦6 mm, PXRES≧10 pixels per mm, PXSIZE≦1.75 μm; and D2≦500 mm. D1 is a distance between the object-side surface of the optical assembly and the imaging surface. D2 is a maximum distance between the object-side surface of the optical assembly and the object plane. PXRES is pixel resolution in the object plane, achieved by the image sensor in imaging the object plane, when the distance between the object-side surface of the optical assembly and the object plane is less than or equal to D2. PXSIZE is pixel size of the image sensor. The invention additionally includes methods for configuring an imaging apparatus for iris imaging.

主权项

1. An imaging apparatus for acquiring an image of a subject's iris for iris image recognition, the imaging apparatus comprising:
an image sensor comprising an imaging surface;and
an optical assembly interposed between an object plane and the image sensor for imaging the object plane onto the imaging surface, the optical assembly comprising an image-side surface and an object-side surface; wherein the imaging apparatus is configured to satisfy the relations: D1≦6 mm; PXRES≧10 pixels per mm; PXSIZE≦1.75 μm; and D2≦500 mm; and wherein: D1 is a distance between the object-side surface of the optical assembly and the imaging surface; D2 is a distance between the object-side surface of the optical assembly and the object plane, such that the absolute value of image magnification (M) corresponding to an imaged object positioned at the object plane is greater or equal to MMIN, wherein:
MMIN=PXRES×PXSIZE; PXRES is pixel resolution in the object plane, achieved by the image sensor in imaging the object plane; and PXSIZE is pixel size of the image sensor.