Large ultralightweight optic fabrication: a manufacturing technology for advanced optical requirements

Optical system designers in the 1990s will require many unique solutions to the issues involved in high quality ground-based and space-based optical systems. To meet the scientific needs of the future, many optical systems will require large apertures which can use segmented, ultralightweight elements. Eastman Kodak Company has developed a number of manufacturing processes for ultralightweight, off-axis optical elements. These processes include mirror core fabrication with an abrasive water-jet system, computer-controlled contour surface grinding, computer-controlled small tool grinding and polishing, and ion beam surface figuring. To allow the engineered design of mirror blanks, a computer-controlled abrasive water-jet system is being used to fabricate ultralightweight mirror cores economically. This paper reviews some techniques for mirror substrate fabrication and lightweighting, including an approach being developed at the Eastman Kodak Company using a computer-controlled abrasive water-jet system