Zooming imaging lens, imaging module and iris recognition device

Abstract

The invention discloses a zooming imaging lens, an imaging module and an iris recognition device. The zooming imaging lens, the imaging module and the iris recognition device belong to the field of biological recognition. The zooming imaging lens comprises a first lens set with a negative focal power and a second lens set with a positive focal power from front to back. The first lens set comprises a first lens with a negative focal power and a second lens with a positive focal power. The second lens comprises a third lens with a positive focal power, a fourth lens with a negative focal power, and a fifth lens with a positive focal power. The first lens, the second lens, the third lens, the fourth lens and the fifth lens are respectively a biconcave lens, a convexoconcave lens, a biconcave lens, a biconcave lens and a convexoconcave lens. The first lens, the second lens and the fifth lens are aspheric lenses. The third lens and the fourth lens are spherical lenses and are adhered together. The distance between the first lens set and the second lens set can be adjusted. The zooming imaging lens has advantages of simple structure, small size, wide zooming range and wide acquisition range. The zooming imaging lens can acquire a high-quality iris image.

Description

technical field [0001] The invention relates to the field of biological identification, in particular to a zoom imaging lens, an imaging module and an iris identification device. Background technique [0002] With the advent of the Internet information age, people's requirements for the security and stability of information, especially personal information, have been continuously improved, and the application of identity authentication by using people's inherent unique physiological or behavioral characteristics has become more and more extensive. Among them, iris recognition technology As the "most accurate" and "hardest to counterfeit" biometric technology is increasingly favored by everyone. However, iris recognition is a biometric technology based on the texture characteristics of the iris of the eye. Since the surface of the iris is spherical, the area is small, and the color is dark, the imaging quality of the optical system for collecting iris images is high. How to o...

AI Technical Summary

Problems solved by technology

[0003] At present, the existing iris collection optical system can be divided into: fixed focus optical system and zoom optical system. Among them, the fixed focus optical system has simple structure, low cost, convenient installation, and meets the requirements of miniaturization. However, due to the single focal length, the shooting range is limited. And it is difficult to achieve a large depth of field. To collect a clear iris image requires a high degree of cooperation from the user; and the zoom optical system can achieve continuous changes in focal length and a wide shooting range without the cooperation of the user. However, the current zoom system volume Large, complex structure, high cost, difficult assembly

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