Fig. 1
Fluorescence detection sensitivity and spatial resolution for detection characterized by ICG solution and resolution target. a Sensitivity is about 5 pM ICG solution, marked by red arrow. Excitation light power is about 20 mW focused at an area of a 200 μm diameter, with a power density of about 0.63 W/mm2. b Resolution test: Group -2 data. c Group -1 data. d Group 0 data. e Group 1 data. f FWHM calculation using Gaussian fit, spatial resolution defined by Sparrow criterion. Element 3 of group 1 is discernible, which indicates spatial resolution for detection is about 397 μm