1. A virtual displaying method of a three-dimensional image for displaying at least one image of a plurality of images, the virtual displaying method comprising: applying a deterioration processing, by a processor, to image data configuring the at least one image of the plurality of the images that configure a virtual three-dimensional image providing a three-dimensional visualization through a lens layer having a plurality of lenses, the image data including color information and α value that represents a transparency in each pixel, the applying of the deterioration process including a semi-transmissive processing to increase a level of the transparency of the image data of the at least one image; and displaying, in a single display, the at least one image obtained by the deterioration processing by the processor.