Neural stimulation with infrared radiation has been explored for brain tissue, peripheral nerves, and cranial nerves including the auditory nerve. Initial experiments were conducted at wavelengths between λ = 1,850 and λ = 2,140 nm and the radiant energy was delivered with square pulses. Water absorption of the infrared radiation at λ = 1,860 nm is similar to absorption at wavelengths between λ = 1,310 and λ = 1,600 nm, which are in the radiation wavelength range used for the communication industry. Technology for those wavelengths has already been developed and miniaturized and is readily available. The possibility of the infrared light to evoke compound action potentials (CAP) in the cochlea at λ = 1,375, λ = 1,460, and λ = 1,550 nm was explored and compared to that of λ = 1,860 nm in guinea pigs. Furthermore, rise and fall times of the 100 μs long pulses were changed and four basic pulse shapes (square, triangular, ramp-up, and ramp-down) were explored in their ability to evoke a CAP. In animals with pure tone threshold averages (PTAs) above 70 dB SPL, the results show that the favorable wavelength is λ = 1,460 nm to reach threshold for stimulation and λ = 1,375 nm or λ = 1,460 nm for obtaining maximum amplitude. The most favorable pulse shape is either ramp-up or triangular.

已经探索了用红外辐射对脑组织、周围神经和包括听神经在内的颅神经进行的神经刺激。最初的实验是在 λ = 1,850 和 λ = 2,140 nm 之间的波长下进行的，辐射能量是用方形脉冲传递的。红外辐射在 λ = 1,860 nm 处的水吸收类似于在 λ = 1,310 和 λ = 1,600 nm 之间的波长处的吸收，这在通信行业使用的辐射波长范围内。这些波长的技术已经开发和小型化并且很容易获得。探索了红外光在 λ = 1,375、λ = 1,460 和 λ = 1,550 nm 处激发耳蜗中复合动作电位 (CAP) 的可能性，并与豚鼠中的 λ = 1,860 nm 进行了比较。此外，改变了 100 μs 长脉冲的上升和下降时间，并探索了四种基本脉冲形状（方形、三角形、斜升和斜降）诱发 CAP 的能力。在纯音阈值平均值 (PTA) 高于 70 dB SPL 的动物中，结果表明有利的波长是 λ = 1,460 nm 以达到刺激阈值和 λ = 1,375 nm 或 λ = 1,460 nm 以获得最大振幅。最有利的脉冲形状是斜升或三角形。