1. An iris code generation method, comprising the steps of: inputting a plurality of images; detecting iris regions from the plurality of images; transforming coordinate system from a rectangular coordinate system to a polar coordinate system for an image of each of the detected iris regions; performing band limitation on each of the coordinate-transformed images; generating an iris code from each of the band-limited images; rotationally compensating each of the generated iris codes in a circumferential direction; and synthesizing the rotationally-compensated iris codes into a single iris code by determining a bit value of each bit based on a majority rule.