When you decide to produce the world largest digital camera without a suitable lens, the you have a tire with no wheels, you are going no where . That can be said to be the genesis of this 5.1-foot wide optic (the largest high-performance optical lens ever made) came to be.
The 3.2-gigapixel camera currently being built for the Large Synoptic Survey Telescope (LSST) has had the idea being cooked up for more than ten years now. But the go ahead was only given 2011, and funding was just gotten in 2015, since then engineers and scientists have been working tirelessly to make this idea a reality.
The camera features the largest CCD image sensor mosaic in the world, merging 189 different sensors into a single 3.2-gigapixel imaging area that (once it’s operational and placed on top of a mountain) it will snap a 15-second exposure of the night sky every 20 seconds or so. This will enable the telescope to capture the entire visible southern sky every few nights!
But a camera sensor is powerless without an optics and in the case of the LSST, it includes three massive mirrors, and two lens elements: the 5.1-foot wide L1 lens element we’re talking about today, and a relatively smaller companion lens element that’s 3.9 feet wide. According to a press release published by the Lawrence Livermore National Laboratory (LLNL), the primary lens is “believed to be the world’s largest high-performance optical lens ever fabricated.”
The two lenses were made by Colorado-based Ball Aerospace and its subcontractor, Tucson-based Arizona Optical Systems, over the course of five years, mounted together in a carbon fiber structure, and then shipped by truck from Tucson, AZ to the SLAC National Accelerator Laboratory in Menlo Park, where there was a bit of a celebration, some fist bumps, and a bunch of photographs taken upon the lens’ safe arrival.
Credit for the creation of this great giant lens goes to LLNL optical scientists Lynn Seppala and Brian Bauman and LLNL engineers Vincent Riot, Scott Winters and Justin Wolfe, whose work “spanning a period of nearly two decades” helped make all of the LSST camera’s optics a reality.