An image display device is provided, by which variations in drive sensitivity of a scan mirror is corrected. Processing executed by a CPU in a laser projector includes the steps of: driving a scanner mirror in a vertical direction; allowing at least one of a green laser and red/blue lasers to emit light; calculating stay time in a light-receiving region in a photoreceptor; comparing the calculated stay time with ideal stay time Tideal; decreasing a tilt of a drive signal for driving the scanner mirror in the vertical direction if the calculated stay time is shorter than the stay time Tideal; and increasing the tilt of the drive signal if the calculated stay time is longer than the stay time Tideal.