Special printing technology that uses binocular parallax and enables viewers to perceive depth is increasing in popularity. In these systems, a high-resolution printout is overlapped by a special optical component, such as a lenticular board or a fly's eye lens. However, determining the best parameters for the optical components, such as the lens pitch and focal length, is not easy. A lot of trial and error is usually needed to make a prototype, which is expensive and time consuming. Moreover, an independent evaluation of the image quality of a 3D display system is difficult because it is hard to remove the influence from the image input system. A new solution to these problems is proposed in this paper. Virtual 3D lenses that have the same functions as real lenses were generated in a 3D space of a CG application by combining some basic objects, such as cylinders, spheres, and boxes. A still image, which was synthesized for integral photography in advance, was texture-mapped onto a box, and the image was observed using a virtual camera that moved horizontally and vertically through the virtual lenses mentioned above. We simulated a kind of integral photography that used two mutually perpendicular lenticular sheets using this method. The results indicated that the proposed method is applicable for designing and evaluating 3D display systems.