3D waveguide penetrating arrays for optical neural stimulation

Early-generation waveguide arrays made of silicon (Si) and fused silica (SiO
₂
) were micromachined for infrared (IR) neural stimulation and optogenetics applications in able to provide comprehensive and selective access to distributed targets. Edge-coupled multimode fibers delivered light through the optrodes. Maximum normalized output power from the tips, with respect to the fiber output, was determined as 0.33 and 0.71 for silicon and glass optrodes, respectively.