METHOD OF MEASURING ZOOM RATIO FOR PROJECTION OPTICAL SYSTEM, PROJECTED IMAGE CORRECTION METHOD USING THE ZOOM RATIO MEASUREMENT METHOD, AND PROJECTOR EXECUTING THE CORRECTION METHOD

摘要

PROBLEM TO BE SOLVED: To provide a technology for improving the accuracy of measuring a zoom ratio of a projection optical system having a zoom function.;SOLUTION: A method includes a step of displaying an image for measurement on a projection screen by projecting image light, which includes a measurement point group in which a plurality of measurement points are arranged on the periphery of a virtual circle, and represents an original image in which the center of the virtual circle coincides with the position of an optical axis of the projection optical system. A plurality of projection measurement points projected and displayed on the projection screen are detected from measurement point detection positions of which the relative position to the projection optical system is fixed. Each position information of the plurality of projection measurement points that are detected is obtained, the position information and a relationship between a preset zoom ratio and the position information are used to determine a zoom ratio of the projection optical system.;COPYRIGHT: (C)2010,JPO&INPIT