| 摘要 |
PURPOSE:To accurately extract a Purkinje image by eliminating the influence of an optical image having extreme brightness due to outdoor daylight and the like. CONSTITUTION:A Purkinje image extracting means is provided with a Purkinje image selecting means for detecting the slope of the rising and the falling of the respective signals of a Purkinje image candidate stored in a memory means for a Purkinje image candidate, selecting a Purkinje image on the basis of the detection results, discriminating the positional relation between the Purkinje image candidate stored in the memory means for a Purkinje image candidate and a pupil, selecting a Purkinje image on the basis of the discrimination results, detecting the number of picture elements in a two-dimensional direction of the respective signals of a Purkinje image candidate stored in the memory means for a Purkinje image candidate, selecting a Purkinje image on the detection results and selecting a Purkinje image on the basis of the intervals which are substantially same in the side-by-side direction of a projecting means at the center of the optical image of the respective Purkinje images stored in the memory means for a Purkinje image candidate. |
