We propose to develop a multimodal imaging instrument that is particularly suitable for real-time measurement of either fluorescence or light scattering at very low intensity levels. The proposed approach is based on controlled spatial and temporal modulation of the illumination field in conjuncture with an efficient integration of the outgoing optical field. The implementation of such a flexible illumination permits using robust and efficient low-light detection schemes that can operate at single photon levels making the entire system compatible with high speed, live-cell imaging requirements. The proposed imaging concept is general and can be applied to both emission (fluorescence) or scattering mode operated in either transmission or reflection. The full temporal and control of the illumination offers exclusive benefits such as adjustable tradeoff between resolution and speed but, most importantly, it allows for an adaptive imaging modality where the resolution is enhanced only in areas of interest within the field of view. Another interesting outcome enabled by the ability to fully control the illumination is the possibility to simultaneously have spatial nd spectral resolution without increasing the measurement time and without using dispersive optical elements and additional instrumentation.
The unique capabilities of the proposed microscopy platform can impact the practice of long term, label-free microscopy where the contrast mechanisms are notoriously weak and also fluorescence based imaging where the activation and emission mechanisms are not very effective or where the control of light exposure is critical to eliminate phototoxicity.