[Music Throughout] The Wide
Field Instrument is the heart of the Nancy Grace Roman Space Telescope.
It is what allows the Roman Space Telescope to take pictures with the same detail
as Hubble, but covering an area 100 times larger.
Despite this incredible power, the basic design is the same as telescopes
around the world. Light enters through Roman's 2.4-meter aperture
and is reflected and focused by the curved main mirror,
which is also the largest mirror in the telescope. This light
is reflected and focused once more by the secondary mirror. More
elements tighten the beam and strip it of stray light rays before it passes through
the filter wheel. This wheel has a variety of filters that
allow different wavelengths of light to pass through. It spins from one
to another depending on what the researcher is looking for.
Finally, the focused and filtered light reaches the focal plane, where it creates an
image on the detectors. These detectors use the photoelectric effect
to convert photons into an electrical signal that is then decoded into
an image. In Roman's case, there are 18 detectors,
allowing it to create 300-million-pixel images of large patches
of the sky. The large number of detectors and
pixels gives Roman its wide field of view. The size of the
mirror and the precision of it optics gives Roman its fine imaging.
This combination of image size and detail has never
been possible on a space-based telescope before and will make the Nancy Grace
Roman Space Telescope an indespensible tool in the future.
Explore: Solar system & beyond. NASA