It's lead sulfide
(PbS) and lead selenide (PbSe) detectors offer the most cost effective choice for standard solutions, while the companies SensIR line of multiplexed linear and two dimensional arrays produce unprecedented array based spectroscopy, remote sensing and IR imaging in the 1-5 micrometer infrared band.
The dots, from 2 to 10 nanometers (nm) across, are typically made of cadmium selenide or lead sulfide
Lead acetate is a water-soluble compound, but lead sulfide
is practically insoluble.
SensArray Infrared is one of only a few companies that have mastered the lead sulfide
and lead selenide infrared imaging technology that is likely to emerge as the material of choice in low cost, high-resolution infrared imaging.