Optical device for simultaneously acquiring human face image and iris image and identity authentication method thereof

The invention discloses an optical device for simultaneously acquiring a human face image and an iris image and an identity authentication method thereof. The device comprises a human face image acquisition module and an iris image acquisition module; the human face image acquisition module is composed of a pre-positioned imaging lens group, a beam splitter prism, a human face camera, an image processing unit and an illumination light source; the iris image acquisition module is composed of the pre-positioned imaging lens group, a beam splitter prism, an iris camera, the image processing unit and the illumination light source; the human face image acquisition module and the iris image acquisition module share the pre-positioned imaging lens group, the image processing unit and the illumination light source; and the separation of a light path of the human face image acquisition module and a light path of the iris image acquisition module is realized by the beam splitter prisms. According to the optical device, the human face image and the iris image of a user can be simultaneously and clearly acquired, and the acquired human face image and iris image have a specific positioning relation, so that subsequence image processing, and extraction of human face features and iris features can be conveniently realized, and the safety is higher.