Patent ID: 8167394

Claim:
An image recording apparatus, comprising: a platen configured to support a sheet fed along a predetermined sheet-feed path; a carriage disposed so as to face to the platen and configured to be movable in a first direction intersecting a sheet-feed direction in which the sheet is fed; a recording head mounted on the carriage and configured to record an image on the sheet fed along the platen; an optical sensor mounted on the carriage and constituted by (a) a light emitting element configured to emit light with predetermined intensity toward a surface facing to the recording head and (b) a light receiving element configured to receive light reflected from the surface facing to the recording head and output an electric signal according to intensity of the reflected light; a changing mechanism configured to change a position of the optical sensor between (a) a first position distant from the platen by a first distance and (b) a second position distant from the platen by a second distance which is different from the first distance; and a calculation section configured to calculate at least one of (a) a distance between the optical sensor and a surface of the sheet and (b) a light reflectivity of the surface of the sheet on the basis of a first electric signal and a second electric signal, wherein the first electric signal is outputted from the light receiving element by receiving light reflected from the sheet disposed on the platen by the light receiving element in a state in which the optical sensor is disposed at the first position while the second electric signal is outputted from the light receiving element by receiving the light reflected from the sheet disposed on the platen by the light receiving element in a state in which the optical sensor is disposed at the second position.