Large field-depth iris image capturing system and method based on multiple cameras with fixed focus

Abstract

The invention which relates to an optical instrument and detection imaging technique discloses a large field depth iris image acquisition system and a method based on a plurality of fixed-focus cameras. The system comprises an iris image collecting device and an image recognition device. The method comprises the following steps: respectively imaging the iris by means of the fixed-focus cameras having different imaging object distance ranges and producing a multi-path fixed-focus image results; choosing one or a plurality of multi-path fixed-focus image results through distance measurement or image quality evaluation method; carrying out image processing and identification of chosen qualified iris image data. The invention effectively integrates the imaging ranges of different fixed-focus cameras in the mode of self-adapting switchover, thereby taking advantages of the cameras and at same time removing disadvantages of the cameras, enlarging the integral imaging range of the acquisition system, and improving the feasibility of an iris recognition system. Compared with the prior iris imaging method adopting a zoom camera, the invention has the advantages of low cost, quick and noiseless focusing.

Description

technical field

[0001] The invention belongs to the technical field of optical instruments and detection and imaging, and in particular relates to a technology for expanding the iris imaging range by using multiple fixed-focus cameras. Background technique

[0002] Safety management has become the focus of attention of the international community. Among many security protection technologies, the identification technology of access control (Access Control) to physical places and information materials is the core technology for public safety and personal family safety protection, and has a wide range of applications in various fields related to the national economy and people's livelihood. For example, units and places such as state agencies, customs, nuclear power plants, military bases, civil aviation airports, railways, bank vaults, energy and mineral resources, scientific research laboratories, archives, office buildings and production workshops of enterprises and institut...

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