Infrared Detectors
JWST needs extraordinarily sensitive detectors to record the faint signals from far-away galaxies, stars, and planets, and it needs large-area detector arrays to efficiently survey the sky. JWST has extended the state of the art for infrared detectors by producing arrays that are both lower noise and larger format than their predecessors. It will use two types of detectors: four mega-pixel near infrared (NIR) mercury-cadmium-telluride detectors for wavelengths 0.6-5 microns, and one mega-pixel mid-IR silicon-arsenic detectors for 5-29 microns.
In April 2006, testing of the near-IR detectors proved that they meet JWST requirements. Testing of the mid-IR detectors was completed in July 2006. Production of both flight detectors types is underway.