Patent ID: 8262234

Claim:
An image display device for optically displaying an image, comprising: a light source; an imaging-light generator converting light emitted from the light source, into imaging light representative of the image to be displayed, to generate the imaging light; a relay optical system focusing the imaging light emitted from the imaging-light generator, on an image plane which is located at an optically conjugate position to the imaging-light generator, the relay optical system defining a pupil through which the imaging light passes, the pupil located within the relay optical system, the imaging light having a minimum diameter at a position of the pupil; a variable-focus lens disposed at a position generally coincident with the pupil, the variable-focus lens having a varying focal length; and a wavefront-curvature adjuster configured to vary the focal length by operating the variable-focus lens, to adjust a wavefront curvature of the imaging light emitted from the relay optical system.