Abstract
We propose a rendering method of diffraction based on bidirectional ray tracing. Light sources and rays have spectral distribution. Apertures or slits which cause the diffraction are modeled by texture mapping on patches in order to simplify the intersection calculation with incident light rays. In light ray tracing, those incident light rays into them are gathered. In eye ray tracing, we use Fraunhoffer approximation to calculate the amplitude of diffracted light from each aperture. We also show some rendered images in which spectral colors and interference fringes are observed.
