Patent ID: 8305297

Claim:
A spectacles-type image display device, comprising: an image output unit for outputting image light of images to be displayed; and a reflection unit disposed in a field of view of at least one eyeball of a viewer, the reflection unit being adapted to reflect the image light output from the image output unit toward the eyeball of the viewer for the viewer being able to see virtual images of the images, wherein, a width, h, of a projection cross-section of the reflection unit in an output direction of the image light satisfies following equation: w·d/f+ 1 ≦h, wherein w is a distance from a pupil position of the viewer to a center of the reflection unit, f is a focal length of a projection lens provided to form the virtual image in the eyeball of the viewer and d is a width of an image display element of the image output unit that corresponds to a width direction of the projection cross-section, where units of respective parameters are in mm, wherein, a minimum value of the width of the projection cross-section of the reflection unit in the output direction of the image light to the eyeball is smaller than a dark-adapted pupil diameter of human and is larger than a light-adapted pupil diameter of human.