스마트폰 카메라 검사용 콜리메이터 광학계 설계 및 분석

Abstract

Analysis of Collimation Optical System for Smartphone Camera Inspection System

Sang Cheol Cho

Department of Image System Engineering, The Graduate School, Pukyong National University

Abstract

“Resolution Test” for Smartphone camera module production is very important. Real distance Resolution Test for camera module have serious problems like testing space, size of chart and backlight lighting size. To solve problem and produce efficiently of camera module, we can use Collimator Lens with reduced system size or system space. First of all, we designed for common 2M Camera module and corresponding Collimator Lens. Camera module contains features of “field angle”, “entrance pupil position” and “filed angle” of 2M camera module. In the design of Collimator Lens, we designed and produced Collimator Lens in the light of “field angle”, “exit pupil diameter” and “exit pupil position” while considering the camera features. In the performance measurement of the collimator lens in design process involves (1) Simulation of collimator lens itself (2) Simulation of 2M smart phone camera module. (3) Simulation of collimator lens combined with smart phone camera module. From tested Ray Aberration, Astigmatic field curves, Distortion and MTF in the performance evaluation of the design process, It is possible to know that the collimator lens is hardly effects on the 2Mega Smart phone module lens. The main purpose of collimator lens, is to obtain the same result as real distance resolution test. Real distance resolution test and resolution test with collimator lens were tested using TV resolution test program and SFR program in the darkroom. In the TV resolution test program and SFR program, It is returned the Resolution test data value in real time. The noise from the real time video, repeat measurement was performed. there is a 50 lines or less in TV resolution test and a variance of 3% or less on the SFR test. The result of TV resolution Comparison test between real distance and 2M camera module combined with collimator lens is 50lines or less. It is the same for less than 3% on SFR comparison test. It was verified that the virtual distance through the collimator lens and real distance are matched