Apodizing Phase Plate Mounted (image) University of Arizona Share Print E-Mail Caption The Apodizing Phase Plate is manufactured in a process called diamond turning. In a phonograph's fashion, a diamond bit engraves grooves at precisely calculated positions into a rotating glass blank. The resulting optic shows only a subtle effect to the eye, but has a big effect on the starlight halo. Shown here is an earlier version now in use at the an observatory on Mount Hopkins, Ariz. Credit University of Arizona Usage Restrictions Usage only in connection with reporting/posting of this news release Share Print E-Mail Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.