Patent ID: 7234813

Claim:
An apparatus for use in an image display, of projecting a light beam onto a retina of a viewer, to thereby allow the viewer to perceive an image, the apparatus comprising: a light emitter emitting a light beam; a scanner scanning the light beam emitted by the light emitter; an optical system receiving the light beam scanned by the scanner as an incoming light beam, and emitting the incoming light beam as an outgoing light beam, such that the outgoing light beam becomes different in a traveling direction from the incoming light beam, so as to be directed to a pupil of the viewer; a curvature compensator compensating a wavefront curvature of the incoming light beam; and a detector detecting a value of the physical quantity, wherein the curvature compensator compensates the curvature of the wavefront of the incoming light beam, based on an entrance position at which the incoming light beam enters the optical system, and the detected value of the physical quantity.