3D-Printed Dual-Color Optogenetic Neural Stimulator

In this letter, we present an optical neural stimulator that utilizes a 3D-printed substrate integrated with conductive wires for electrical connections and micro light-emitting diodes (
$\mu $
LEDs) for optogenetic stimulation. The proposed device includes two different color LEDs for excitation and inhibition of the targeted neurons on the single optogenetic electrode (optrode). The proposed device is unique in that it is built mainly with 3D-printed custom-made components without the need for microfabrication techniques, allowing for the easy design and manufacture of small, complex shapes without the use of clean-room facilities. The total thickness of the device is just
$85~\mu \text{m}$
, generating enough light intensity to excite and inhibit the neurons. The measured electrical, optical, and thermal properties of the device validate the device’s characteristics and functionality.