Image-forming element and image display device

An image display device comprising:

• an image-forming element comprising:
• a base member including a first surface, and a second surface opposite the first surface, and
• a reflector array located on the base member;
• and
• a light source configured to irradiate light on the image-forming element;
• wherein:
• the reflector array comprises a plurality of reflector rows, each including a plurality of dihedral corner reflectors arranged along a first direction;
• the plurality of reflector rows are arranged in a second direction crossing the first direction, the plurality of reflector rows being parallel to each other with a spacing therebetween;
• each of the plurality of dihedral corner reflectors includes:
• a first reflecting surface configured to reflect light from a first surface side, and
• a second reflecting surface orthogonal to the first reflecting surface and configured to reflect a reflected light from the first reflecting surface toward the first surface side;
• in each of the plurality of reflector rows, an angle between (i) a straight line at which the first and second reflecting surfaces cross, and (ii) a virtual plane including the first and second directions, is set to a value greater than 0° and less than 90°;
• an angle between the first reflecting surface and the virtual plane is greater than 45° and less than 90°,
• the plurality of reflector rows include a first reflector row of which the angle between the straight line and the virtual plane is set to a smallest value among the plurality of reflector rows,
• for reflector rows other than the first reflector row, the angle between the straight line and the virtual plane is set to values that increase away from the first reflector row in one direction along the second direction;
• the light source is located at the first surface side;
• and
• each of the plurality of dihedral corner reflectors is arranged so that a portion of a light emitted from the light source and once-reflected by the first reflecting surface travels toward the second reflecting surface, and another portion of the reflected light travels toward the second surface side.