Image display apparatus

摘要

An image display apparatus includes a diaphragm ( 9 b) arranged at a pupil position. The shape of an aperture of the diaphragm ( 9 b) is similar to the shape of a light source image formed by an illuminating optical system at the pupil position. An area varying mechanism ( 90 ) varies the area of the aperture of the diaphragm ( 9 b) in response to a focal length varying operation of a projection lens ( 9 ). This prevents an excessive opening from being formed around a light source image cast by the illuminating optical system, thereby preventing the deterioration of displayed images due to unwanted light that may pass through the excessive opening.