One layer of semiconductors--a mixture of mercury, cadmium, and telluride--records the near-infrared radiation
, while a layer of silicon bonded to this material reads out the electronic signals.
Although these materials have very low visible-light transmittance levels, they transmit an unacceptably high level of near-infrared radiation
Giovanni Verri, a physicist in the museum's department of conservation and scientific research, developed a technique to exploit the fact that Egyptian blue emits near-infrared radiation
when excited by visible light.
As recently as a decade ago, no one envisioned detecting near-infrared radiation
from the face of Venus, To reach an orbiting telescope, for example, heat radiated from the surface must pass through dense layers of carbon dioxide - a gas that absorbs most nearinfrared light.