LGSF top-end mechanical layout showing the asterism generator, the collimator and laser launch telescope.
TMT refrigeration prototype for NFIRAOS first-light adaptive optics system has been developed by the Technical Institute of Physics and Chemistry of the Chinese Academy of Sciences (TIPC) in Beijing and arrived at the NRC Canada's Herzberg Astronomy and Astrophysics Research Centre in Victoria.
The refrigeration prototype will be used for the cooling of TMT's Narrow Field Infra-Red Adaptive Optics System enclosure.
The entire optical test system was packed and crated by AOS & TMT staff and then transported by truck.
Beam Launch and Imaging System (BLIS). The BLIS sub-system will be installed at the top of a five-story test for measurement of an M1 segment assembly below at the bottom of the tower. The side covers have been removed in the picture on the left, showing the mechanical setup and cable routing of the imaging and illumination system. At center, the access door allows the technician to exchange the computer-generated hologram (CGH) to match the type of M1 segment that is being measured.
The telescope structure system provides structural support and precise motion, and also space for accessing and servicing the telescope optics, their associated systems (M1S, M2S, M3S), the science instruments, adaptive optics systems, and auxiliary systems. STR cradles the TMT’s 492 articulated mirror segments as they relay the light of astronomical bodies to the M2 and M3 mirrors and finally to the several science instruments located on both lateral Nasmyth platforms
TMT STR serves as the skeleton and muscles of the telescope and thus interfaces with various instrumentation, optics, and controls subsystems. TMT STR will hold the TMT's optics and smoothly tracks celestial targets as they move across the sky. For perspective, the telescope is ~55m (180 feet) wide and ~50m (160 feet) tall.
Following a detailed shipping and storage procedure plan, Coherent personnel carefully handle the large optics for TMT’s Primary Mirror.
A highly qualified Coherent inspector verifies the roundel surface of each TMT finished roundel before it is sealed up in its packaging at the supplier’s facility.
Glen Cole, TIO Lead Optical Fabrication Engineer, visits Coherent’s production unit dedicated to TMT while observing strict safety protocols due to the Covid-19 pandemic.
Highly protected and covered by optical paper, the roundel is ready to be shipped to TIO’s storage facility.
On March 3, 2021 in Tucson AZ, AOS successfully demonstrated the metrology system they have built to measure the aspheric prescription of the TMT primary mirror segments. This test set uses a full-aperture reference surface and a Fizeau interferometer to measure the curvature of the off-axis segments. This test set will guide the Ion Beam Figuring process which will bring the TMT segments to their final surface figure requirements.
