곡면 패널 검사를 위한 효율적인 오토 포커싱 방법

다국어 초록 (Multilingual Abstract)

The curved panel is widely used for display of TVs and smart phones. This paper proposes a new auto-focusing method for curved panel inspection system. Since the distance between the camera and the panel varies with the curve position, the camera should change its focus at every inspection time. In order to reduce the focusing time, we propose an effective focusing method that considers the mathematical model of panel curve. The Lagrange polynomial equation is applied to modeling the panel curve. The foci of initial three points are used to get the curve equation, and the other foci are calculated automatically from the curve equation. The experiment result shows that the proposed method can reduce the focusing time.

목차 (Table of Contents)

• Abstract
• 1. 서론
• 2. 개선된 자동e점 알고리즘
• 3. 실험 결과
• 4. 결론
• References

참고문헌 (Reference)

• 1 윤희상, "소형 카메라 모듈용 테스트 핸들러의 자동 초점 조절 방법" 제어·로봇·시스템학회 12 (12): 168-173, 2006
• 2 S. K. Nayer, "Shape from Focus" 16 (16): 824-831, 1994
• 3 K. S. Choi, "New Autofocusing Technique using the Frequency Selective Weighted Median Filter for Video Cameras" 45 (45): 820-827, 1999
• 4 J. He, "Modified Fast Climbing Search Auto-Focus Algorithm with Adaptive Step Size Searching Technique for Digital Camera" 49 (49): 257-262, 2003
• 5 G. J. Nam, "Measuring Color Defects in Flat Panel Displays Using HDR Imaging And Appearance Modeling" 65 (65): 297-304, 2016
• 6 K. S. Pradeep, "Improving Shape from Focus Using Defocus Cue" 16 (16): 1920-1925, 2007
• 7 J. H. Lee, "Implementation of a Passive Automatic Focusing Algorithm for Digital Still Camera" 41 (41): 449-454, 1995
• 8 M. Subbarao, "Focusing Techniques" 32 (32): 2824-2836, 2005
• 9 W. Huang, "Evaluation of Focus Measures in Multi-Focus Image Fusion" 28 (28): 493-500, 2007
• 10 N. Kehtarnavaz, "Development and Real-time Implementation of a Rule-based Auto-Focus Algorithm" 9 (9): 197-203, 2003
• 11 W. C. Li, "Defect Inspection in Lowcontrast LCD Images Using Hough Transform-based Nonstationary Line Detection" 7 (7): 136-147, 2011
• 12 Y. Gan, "An Effective Defect Inspection Method for LCD Using Active Contour Model" 62 (62): 2438-2445, 2013
• 13 J. M. Tenenbaum, "Accommodation in Computer Vision" Stanford University 1970
• 14 S. H. Shin, "A Study on a New Auto-Focusing Algorithm for Digital Cameras" 50 (50): 447-453, 2001
• 15 T. Koizumi, "A New Optical Detector for a High-speed AF Control" 42 (42): 1055-1061, 1996