Patent ID: 7405881

Claim:
An image display apparatus comprising: a light source for emitting a light at different wavelengths corresponding to the three primary colors; a display device for displaying an image through modulating the light emitted from the light source at each pixel; and an eyepiece optical system for directing the image received from the display device to the pupil of a viewer, wherein each pixel in the display device is driven in a time-division mode in response to each of the three primary colors of the light emitted in a time-division sequence from the light source, and the eyepiece optical system includes a hologram optical element for diffracting the light at difference wavelengths corresponding to the three primary colors emitted from the light source, and the displacement of the peak position of the intensity in the optical pupil formed by the eyepiece optical system is not greater than 1 mm between any two of the three primary colors; and when the wavelength range at half of the diffraction efficiency of each of the three primary colors of the light in the hologram optical element and the wavelength range at half of the intensity of each of the three primary colors of the light emitted from the light source are Δλ 1 and Δλ 2 respectively, a relation of Δλ 1 <Δλ 2 is established for each of the three primary color.