DESI Project Delivers Major Optical Elements

The Dark Energy Spectroscopic Instrument (DESI) project has delivered major optical elements to Arizona Optical Science and L3-Brashear for figuring and polishing. Above is an image of the largest corrector lens, C1 measuring 1.15m in diameter. The homogeneity of the fused silica glass came in at an astounding 1ppm (exceeding the 3ppm spec). DESI will be conducted on the Mayall 4-meter telescope at Kitt Peak National Observatory starting in 2018.