Lifetime Imaging of Luminescent Oxygen Sensors Based on All-Solid-State Technology

Conventional lifetime imaging requires rather complex and expensive instrumentation, like lasers and intensified CCD−cameras. We demonstrate that an array of light-emitting diodes and a directly gatable CCD−camera can be alternatively used for special applications as, for example, imaging of oxygen concentrations on a surface covered by an optical sensor. The suitability of low-cost devices is in this case favored by the microsecond decay times and the spectral properties of highly luminescent ruthenium(II) complexes. For an illuminated sensor area of 5 cm 2 and an aimed spatial resolution of 1 mm, oxygen resolution was better than Δ P O 2 = 0.4 Torr in the absence of oxygen and Δ P O 2 = 2.5 Torr at P O 2 = 100 Torr.