Patent ID: 7072085

Claim:
An image combiner comprising a reflective type holographic optical element, wherein the image combiner superimposes light from outside on light from an image display unit that emits light having wavelength region components respectively extending before and after at least one peak wavelength, wherein: a wavelength λ o and a wavelength λ y are different, where λ o is a wavelength at which a diffraction efficiency of the reflective type holographic optical element has a maximum value in the wavelength region in the vicinity of one peak wavelength for chief rays that are emitted from a center of a display part of the image display unit and diffracted by the reflective type holographic optical element, and where λ y is a wavelength at which the diffraction efficiency has a maximum value in the wavelength region in the vicinity of said one peak wavelength for chief rays that are emitted from peripheral portions of the display part and diffracted by the reflective type holographic optical element.