Hello,
someone asked me the question below. I thought it could be of interest to you all. > My interest: a digital sundial. Is such a thing possible with Moire > gratings? Yes! [EMAIL PROTECTED] has developed such a kind of sundial. It consits of one regulary spaced grating and another one placed parallel to the first in a distance of about one centimeter (some sort of plexiglas inbetween). The second grating is not regualar. It is made in such a way that the sunlight casts digits on a plane depending on the hour angle of the sun. This kind of a digital sundial shows a different time every five minutes. Please contact Hans Scharstein for more details! Regards - - Daniel Roth, sundial mailing list
