Design of 5 mega-pixel imaging lens for iris recognition

With deep research, iris recognition technology is expected to be widely used in field of mobile payment. In view of big volume and quality of current iris recognition lens, Zemax optical design software is used to design compact 5 mega-pixel iris recognition lens composed of three-piece non-spherical structure. Lens working distance is 170 mm ~ 250 mm, F number is 3, total length of lens is 4.43 mm, optical distortion is less than 2%, TV distortion is less than 0.5%, relative illumination is less than 0.6. Matching 1/4" CMOS made by APTINA, Nyquist frequency of 357 lp / mm, at 1/2 Nyquist frequency, MTF are greater than 0.2, total pixel can reach 5 mega-pixel. Image quality evaluation and tolerance are analyzed. Results show that lens meet optical requirements.