An uncoated conversion surface facet. The conversion surface is a diamond-like carbon coated on a facet cut out from a highly polished silicon wafer. IMAP-Lo will have 28 conversion surfaces. The conversion surface enables detection and characterization of the interstellar atoms of energies from 10 to 1000 eV. The interstellar atom hits the conversion surface and converts to an ion, which is next analyzed by the other subsystems (ESA+TOF) of the IMAP-Lo detector.