A digital planetarium apparatus includes an original image generator, an
intermediate image generator, and a fish-eye lens. The original image
generator is formed of two video projectors and generates semicircular
images in display devices inside the respective video projectors. The
intermediate image generator optically focuses the two semicircular
images generated by the original image generator to thereby generate a
circular image. The fish-eye lens projects the circular image generated
by the intermediate image generator.