Pixel imaging mass spectrometry with fast silicon detectors

We report on ‘proof of concept’ experiments in pixel imaging mass spectrometry (PImMS) using an ultra-fast frame-transfer CCD camera. The fast framing CCD camera is capable of recording and storing on-chip up to 16 separate images corresponding to different mass fragments, with a time resolution of 10 ns. In addition to the standard mass spectrum, the technique allows recording of the spatial or velocity distributions of the ions at their point of formation within the instrument. Our results unambiguously demonstrate the feasibility of technique, but it is also clear that the CCD camera restricts the total number of masses that may be imaged to an unacceptably small number. We describe possible CMOS pixel detectors capable of considerably improving the achieved performance in order to meet the demanding requirements for complete recording of mass spectra of complex organic molecules.