APPARATUS AND METHOD FOR CONTROLLING AUTO EXPOSURE OF DIGITAL CAMERA

摘要

An apparatus and a method for controlling auto exposure of a digital camera are provided to attach a liquid crystal filter to an optical signal input terminal of a camera lens to control transmissivity of a optical signal inputted through the lens and enable auto exposure control of a desired pixel region of a camera image. An apparatus for controlling auto exposure of a digital camera includes a liquid crystal filter(14), a liquid crystal driver(15), and a controller(16). The liquid crystal filter includes a plurality of cells interposed between two glass substrates and each of the cells controls transmissivity of an optical signal inputted to a photo-electric converter(13) of the digital camera. The liquid crystal driver varies arrangement of liquid crystal molecules of the cells of the liquid crystal filter by adjusting a voltage difference of electrodes for the cells to control transmissivity of light which is transmitted through each cell of the liquid crystal filter. The controller controls the liquid crystal driver to analyze a camera image signal transmitted from the photo-electric converter in a software manner when an auto exposure control mode is set to control transmissivity of optical signals transmitting cells of the liquid crystal filter, which correspond to a pixel region having an illumination level higher than a predetermined illumination level.