position detection unit, and the lens unit, camera, and a method of manufacturing the lens unit having the same, position detection how

摘要

PROBLEM TO BE SOLVED: To provide a position detection unit capable of detecting an absolute position without moving a detection object to a predetermined reference position at the time of startup.;SOLUTION: A position detection unit in the invention comprises: a first sensor (20) for outputting a monotonically increasing or decreasing monotone signal to displacement of a detection object (16); a second sensor (24) for outputting two sine signals with phases mutually shifted to the displacement of the detection object; a first storage part (26) for storing the monotone signal to a position of the detection object; a second storage part (26) for storing a maximum value and a minimum value of each of the sine signals; and a position calculation part (28) for, on the basis of the detected monotone signal and stored monotone signal data, identifying in what number cycle of the sine signals the detection object is positioned, and calculating the position of the detection object within the identified cycle on the basis of the detected sine signals and the stored maximum and minimum data, and then obtaining an absolute position.;COPYRIGHT: (C)2013,JPO&INPIT