Credit: NAOJ
From left to right: A CLEARCERAM®-Z zero thermal-expansion glass mirror blank cast by OHARA Inc. in Japan, a prototype of TMT Primary Mirror Assembly, and a spherical glass precisely grinded by Okamoto Optics in Yokohama. Exhibits were featured at the Optics and Photonics International Exhibition, 25-27 April 2018 in Yokohama, Japan.