Projector and processing line specification method

Abstract

A projector of the invention includes: a projection lens that is movable in a direction substantially perpendicular to an optical axis to project and display an image on a projection object; an imaging structure that photographs an area including at least the projected image on the projection object to take a photographed image; a shift level detection unit that detects a shift level of the projection lens; a control module that specifies a reference line to be processed in the photographed image; and a storage unit that stores a map of positional information to each shift level, where the positional information represents an expected relative line position to the projected image included in the photographed image. The control module specifies a display position of the projected image included in the photographed image, reads the positional information corresponding to the shift level detected by the shift level detection unit from the map stored in the storage unit, and specifies the reference line, based on the expected relative line position represented by the read positional information and the specified display position of the projected image. Even under the condition of a shift of the projection lens, the projector of this arrangement distinctly identifies the position of maximum brightness in the photographed image and thereby ensures accurate and adequate keystone correction and other required image processing operations.

Dependencies are inferred from the claim text.