The present invention related to an auto focus intraoral camera. The auto focus intraoral camera includes an illumination module for providing illuminating light, an imager, and a lens system for collecting light reflected from an object and focusing the light onto the imager, wherein said lens system further comprises at least one liquid lens including a vessel filled with a first liquid, and a second liquid being in contact with said first liquid, the first and second liquids being immiscible, of different optical indexes, and of substantially same density wherein the lens system further includes a driver integrated circuit applying variable voltage to control the focal length of said lens. According to the present application, a compact auto focus intraoral camera with a small size and simple structure is provided, which decreases the camera complexity and improve the performance.
