Mark Optics had a close, professional interaction with Cal Tech senior astrophysics engineers to define telescope filter specifications, and subsequently devise a precise manufacturing plan to fabricate these substrates for both the Cal Tech and Palomar telescopes.
The manufacturing plan had to account for a number of specific, high-tolerance linear characteristics required for the telescopes, including interferometry to ensure that transmitted wavefront error was to specification.
After painstaking efforts by the Mark Optics manufacturing team to craft a set of detailed process instructions to fabricate several identical substrates, they were able to ship each tested substrate ahead of schedule.
In addition, Mark Optics saw a 100% yield with the manufacturing effort to fabricate these precise telescope filter substrates.