Optical Telescope Element

Optical Telescope Element (OTE) is one of three major sections of the James Webb Space Telescope, a large infrared space telescope launched on 25 December 2021, consisting of its main mirror, secondary mirrors, the framework and controls to support the mirrors, and various thermal and other systems. The OTE collects the infrared light and directs it to the science instruments in Webb's second major section, the Integrated Science Instrument Module (ISIM).

Source: Wikipedia — Optical Telescope Element (CC BY-SA 4.0)