Dual-mode optical imaging system for fluorescence image-guided surgery.

In this Letter, we present a novel imaging concept that a single imaging system can image different spectral bands with different aperture sizes. It is achieved by using a filter with different transmitted spectral bands in different annular rings as the aperture stop. This concept will enable more efficient system configurations and practical clinical applications. We have demonstrated this concept with a dual-mode near-infrared fluorescence image guided surgical system.