Fast Auto-Focus Control Algorithm Using the VCM Hysteresis Compensation in the Mobile Phone Camera

Author

Kim, Tae-Kyu ; Sohn, Jae-Sik ; Lee, Suk-Hwan ; Kwon, Ki-Ryong ; Kim, Duk-Gyoo

Author_Institution

Sch. of Electr. Eng. & Comput. Sci., Kyungpook Nat. Univ., Taegu

Volume

3

fYear

2006

fDate

14-19 May 2006

Abstract

A practical real-time auto-focus algorithm for a digital camera is presented in this paper, and it improves the reliability and speed of the auto-focus process, especially suitable for a 2 mega-pixel high definition camera. The proposed algorithm divides auto-focusing process into several modes and finds the focus by the different control current in the each mode. Additionally, an adaptive step size searching and a hysteresis compensation of the voice coil motor increased searching speed. The experimental result shows the proposed algorithm is faster auto-focusing than conventional algorithm in the VCM camera system

Keywords

cameras; focusing; mobile handsets; search problems; 2 mega-pixel high definition camera; VCM hysteresis compensation; adaptive step size searching; auto-focus control algorithm; mobile phone camera; voice coil motor; Coils; Computer science; Digital cameras; Flowcharts; Focusing; Frequency; Hysteresis motors; Industrial training; Lenses; Mobile handsets;

fLanguage

English

Publisher

ieee

Conference_Titel

Acoustics, Speech and Signal Processing, 2006. ICASSP 2006 Proceedings. 2006 IEEE International Conference on

Conference_Location

Toulouse

ISSN

1520-6149

Print_ISBN

1-4244-0469-X

Type

conf

DOI

10.1109/ICASSP.2006.1660872

Filename

1660872