After a plurality of parallax images either obtained from an external camera or generated by a computer are divided into a plurality of image strips, respectively, a combined image is formed from the plurality of image strips, and recorded on a photo sensing drum as a latent image. Next, the latent image is transferred or printed on backside of a lenticular sheet, made from a transparent plastic, with toner or ink, thereby forming a stereoscopic image display medium. Accordingly, a high definition stereoscopic image of good contrast can be printed out at high speed by using a printer having a simple configuration.