Optics of Iris Imaging Systems
Iris imaging systems must capture iris images of sufficient quality to populate an enrollment database or to provide probe images that reliably match to existing enrollment images. From whatever distance they are taken, the iris images must therefore resolve information from the iris sufficient for the task of recognition. This chapter reviews concepts of optics and photography needed to specify requirements on the image acquisition components of systems which create iris images for the purpose of recognition. We consider fundamental and practical limitations of components of such systems and consider as examples, iris imaging systems that operate at 0.3 and 3 m on constrained and relatively unconstrained subjects.
KeywordsSpatial Frequency Point Spread Function Image Sensor Modulation Transfer Function High Spatial Frequency
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