Key Laboratory of Quantum Information, Chinese Academy of Sciences, Optics and Optical Engineering Department, University of Science and Technology of China, Hefei, Anhui 230026, China
With the development of optical information processing technology, image edge detection has been widely used in optical high-contrast imaging, automatic driving, face recognition, astronomical observation and other fields. Optical edge detection mainly employs 4-f spatial filtering imaging system with a filtering element in a Fourier plane to modify the spectral information of the image,which results in a strong edge enhancement of object structures. In this paper, several different methods of optical image edge detection and their theoretical analyses are demonstrated. Besides, relevant research progresses at home and abroad are reviewed.