Author(s)

Qian Liang and Yahui Zhang

Corresponding Author

Yahui Zhang

ABSTRACT

Modern optical system needs to achieve high-resolution imaging through precise focusing, and auto focusing, as a product of modern technology, has become a trend of optical system design. The main approach of auto focusing is to drive the focusing mechanism through the focusing information generated by the relevant methods or algorithms of optical principles and computer science, and adjust the position of the focusing lens group or detector in an automatic way to meet the Gauss imaging formula, so as to make the system ideal imaging. Starting from the imaging principle of optical system, this paper discusses the characteristics of optical system focusing, the reason of defocusing and the structure of auto focusing. Then this paper summarizes the main methods of autofocus, and divides them into four categories according to their characteristics, which are defocusing modeling, focusing based on image detection, focusing based on image processing and Focusing based on artificial intelligence. Through the elaboration and analysis of four kinds of methods, the current trend of autofocus is understood and the future development trend is forecasted.

KEYWORDS

Auto Focus, Ranging Method, Image Detection, Image Processing, Artificial Intelligence