Image pickup apparatus for focusing an object image based on mirror reflected height of the object

摘要

An image pickup apparatus for reading an object having a curved document surface such as an opened book, constructed to focus an optical system all the object. A line sensor is moved for scanning the object, thereby a distance between the line sensor and the object is measured, and the object is imaged while controlling an optical system based on data of measured distance so that an object image is in focus on the line sensor. This allows all over the object surface to be in focus, whereby the clear image without blur is obtainable.