Disclosed is an optical unit for an image display device, the unit including: one or a plurality of light sources; one or a plurality of optical elements that control a spread of light; a combining element that combines the beams of light emitted from the light sources; and a scanning element, wherein the light from each of the light sources generates an elliptical beam spot on a screen and the spot has a major axis substantially perpendicular to a scanning direction, the result is that the unit is simple in structure, inexpensive, compact, lightweight, and capable of providing high-resolution image quality, thus providing the display device reduced dimensionally and in weight. Such an image display device using the optical unit is also disclosed.