IRIS RECOGNITION OPTICAL SYSTEM HAVING SHORT TOTAL LENGTH

摘要

An iris recognition optical system having short total length includes first lens having positive diopter and second lens having negative diopter and axially disposed in alignment with first lens. The first lens includes second reflecting surface located on object side around optical axis, first transmissive surface with concave curvature located on object side around second reflecting surface and exhibiting vertical profile relative to said optical axis, second transmissive surface located on image side around optical axis, and first reflecting surface located on image side around second transmissive surface. As first lens is configured to provide two opposite reflecting surfaces, focal length of system can be greatly shortened, and therefore, the system can be installed in cell phone, smart phone, tablet computer, notebook or any other low-profile mobile electronic device, allowing product user to easily and stably get iris images from a distance of about 300 mm.

主权项

1. An iris recognition optical system having short total length, comprising:
a first lens having a positive (+) diopter; and a second lens having a negative (−) diopter and axially disposed in alignment with said first lens; wherein said first lens comprises a second reflecting surface located on an object side around an optical axis thereof, a first transmissive surface located on said object side around said second reflecting surface and selectively exhibiting a vertical or concave profile relative to said optical axis, a second transmissive surface located on an image side thereof around said optical axis, and a first reflecting surface located on said image side around said second transmissive surface.