The Wide Field Instrument (WFI) is a 300-megapixel infrared camera, operating in the 0.48 – 2.3 micron range. The WFI will have 18 detectors covering a 0.8 degree x 0.4 degree or 0.281 deg2 field of view (excluding detector gaps) with 0.11 arcsecond x 0.11 arcsecond pixels, eight imaging filters, two slitless spectroscopy modes with a grism and a prism, and a blank for dark current and flat field measurements (using the internal calibration system). The WFI instrument parameters can be found here. More technical information is available on NASA/Goddard Roman Space Telescope's WFI technical page.
The WFI will be used in the High Latitude Wide Area and the High Latitude Time Domain Surveys to study the nature of dark energy and dark matter, and the Galactic Bulge Time Domain Survey to search for exoplanets (both bound and unbound) using the microlensing technique, as well as in General Astrophysics Surveys that will be proposed by the astronomical community at large.
