[2] [2] MA Heng-kuo, WEI Guo-qiang. Based on image processing the study of stability of automatic focusing method［J］.Aviation Precision Manufacturing Technology, 2007, 43(2): 33-36.

[3] [3] ZHU He, LIANG Wei, GAO Xiao-dong. Aviation camera optoelectronic autocollimation focusing system［J］. Photoelectric Engineering, 2011, 38(3): 35-39.

[4] [4] SHI Lei, JIN Guang, TIAN Hai-ying, et al. Aviation camera automatically examines autocollimation method research［J］. Optical Precision Engineering, 2008, 16(12): 2460-2464.

[5] [5] WANG Yong, TAN Yi-hua, TIAN Jin-wen. A new image sharpness evalution function［J］. Journal of Wuhan University of Technology, 2007, 29(3): 124-126.

[6] [6] CAI Ming-rong, MA Jun-shan, WANG Fu-hong. Automatic focusing system in the research of image resolution discriminant method［J］.Optical Instrument, 2008, 30(5): 35-39.

[7] [7] MU Hong-xin, WU Qing-chang, ZHANG Cui, et al. An improved mountain climb searching algorithm in auto-focusing［J］.Journal of Kunming Metallurgy College, 2010, 26(3): 32-35.

[8] [8] LIU Chun-tong, ZHANG Yang, HE Zhen-xin, et al. Optimization design of automatic focusing and climbing mountain searching algorithm in electronic theodolite system［J］. Computer Measurement & Control, 2014, 22(4): 1178-1181.

[9] [9] HE Zhen-xin, LIU Chun-tong, HUANG Xian-xiang, et al. Auto focus search algorithm based on MTF assisted positive focus judgment［J］. Acta Photonica Sinica, 2014, 43(4): 0411002.

[10] [10] WEI Yu-ke, LI Jiang-ping, DUAN Yang-guang, et al. An automatic focusing algorithm for tongue image acquisition based on image processing［J］. Journal of Shandong University (Engineering Science), 2011, 41(4): 95-100.

[11] [11] ZHOU Jiu-fei, ZHAI Lin-pei, ZHOU Gang, et al. Automatic method of aerial imaging device［J］. Acta Optica Sinica, 2010, 30(1): 105-108.

[12] [12] YUAN Yu-kai. Automatic focusing method for optical system［J］. Infrared, 2004, (6): 15-21.

[13] [13] XU Zhao-lin, ZHAO Yu-liang, ZHANG Guo-dong. New type of automatic aerial camera focusing system design［J］. Lightning and Control, 2011, 18(4): 77-80.

[14] [14] GONG Guang-yong, HE Wen-zhong, GAO Cu-hui. Infrared automatic focus mountain climbing searching algorithm in the system optimization design［J］. Laser and Infrared, 2007, 37(11): 1213-1215.

[15] [15] YANG Quan, LIU Jing-hong, MA Xiao-fei. Auto-focusing method based on image processing for airborne electro-optical imaging platform［J］. Chinese Journal of Liquid Crystals and Displays, 2011, 26(5): 677-682.