Optical innovations in the James webb space telescope

摘要

Researchers has build the new James Webb Space Telescope (JWST) that will have infrared-only detectors to catch photons from the earliest days of the universe, and to avoid thermal noise it will orbit the sun in distant gravitational lockstep with the Earth. Three of JWST's four detecting instruments will operate in the near-infrared range, from just shy of 1 μm to 5 μm, the fourth will cover the range from 5 to 29 μm. Astronomers will cast their initial net at short wavelengths and then plan additional mid-infrared observations to study the properties of newly discovered objects. The secondary mirror of telescope will focus the light into the aft optical subsystem, which contains the tertiary mirror and a fine-steering mirror that helps to stabilize the image. The Integrated Science Instrument Module (ISIM), essentially a truss made of carbon-epoxy composite, holds the four scientific payloads in place. Each of the instruments in the ISIM has a pick-off mirror that can capture the light beam and route it into the chosen instrument.