Laser Vision Helps Package Shippers See Clearly

For more than 25 years, the Hubble Space Telescope has provided stunning photos of the universe unequalled in their depth, detail, and distinction. But in its early days, Hubble wasn't capable of sending back such breathtaking photos. Within weeks of launch, the images beamed back to Earth were fuzzy and out of focus. It was determined that Hubble's primary mirror had been ground to the wrong shape and was too flat by 2.2 micrometers, causing reflected light from the edge of the mirror to be focused on a different point than light coming from near the center. It was determined that the device used to create the nonspherical mirror had been incorrectly assembled, and the mirror's manufacturer had failed to notice the problem before Hubble was launched.