Extended Data Fig. 2. Power attenuation and estimated focal energies at depth with 1300 nm excitation of brain tissue including cortex, corpus callosum (white matter) and hippocampus.
a, THG signal attenuation vs depth in the mouse brain with fits displaying attenuation length (EAL) in the cortex (red, EAL = 275μm), white matter (yellow, EAL = 101μm) and hippocampus (purple, EAL = 250μm). The brightest 0.5% of pixels of each THG image slice were averaged. The cube root of the resulting average was scaled by the surface power, and the entire curve was normalized by the maximum. b, Estimated theoretical focal energy (2nJ straight line and 1nJ dotted line) for a given surface power P0 based on attenuation length determined in (a) (P(z) = P0*exp(-z/EAL). Experimental power values used for Extended Data Fig. 3 are plotted as blue dots. Heating threshold taken from Ref. 21.