1. A stereoscopic image display apparatus comprising: an image display unit which displays a plurality of images for a right eye and images for a left eye by using different pixels; and a masking member having apertures through which light fluxes of a plurality of images for the right eye and the left eye, respectively directed to a right eye observation region and left eye observation region, pass, wherein a region where no images are presented exists between the right eye observation region and the left eye observation region.