During the past two decades, optical super-resolution microscopy techniques have have slowly transfermed the way we performoptical imaging in biology. Several superresolution modalities are now commercialized, among which one can find emission depletion microscopy (STED), stochastic activation based imaging (PALM/STORM), structured illumination microscopy (SIM) and Image Scanning Microscopy (ISM). IsEach of these presents a certain choice of tradeoffs between system performance (including, for example, imaging speed, resolution and sensitivity), cost, and experimental complexity. The addition of more tools to this palette of available methods is likely to facilitate penetration into new biological applications and expansion of the entire superresolution imaging market.
The SFICAM project was dedicated to the development of a detector system based on a fan-out fiber bundle where each fiber in the bundle is connected to a single photon detector, enabling imaging of single photons and their correlation accross a small field of view. In parallel to the development of this hardware, the projact aimed to develop methods that will make this type of hardware attractive. Throught this we developed quantum ISM (Q-ISM)- an expansion to the image scanning mirscopy method. Q-ISM requires the ability to rapidly detect single photons as the mesaured parameter is not photon number but rather the number of observed correlated photon pairs. Taking advantage of the fact that typical markers in fluorescence microscopy cannot emit more than one photon at a time, these correlations contain information with higher spatial resolution. We showed how this can be exploited to enhnace the resolution of a confocal microscope both laterally and axially, at the expense of a longer integration. Work is currently underway to identify possible routes for commercialization of the technique.
