Development of a Wireless High-Frequency Microarray Implant for Retinal Stimulation - Artificial Sight: Basic Research, Biomedical Engineering, and Clinical Advances - page 171

Figure 9.3. Biphasic waveform.
not been extensively investigated in a retinal implant. Therefore, the design and
fabrication of a device that allows for an array of stimulation waveforms and
electrode size and spacing variation would be very useful for understanding the
effects on neural stimulation. Further, if the device can sense neural signals
as feedback, a greater understanding of neural stimulation effects could be
obtained.
There are two approaches to implanting the stimulator array. They are
epiretinal implant and subretinal implant (Figure 9.4). In both the cases, the
stimulation is done by microelectrodes on the stimulator array arranged as a
two-dimensional array. We are pursuing a subretinal implant based on an RF link
for data and power transfer [2, 3]. As the subretinal implant goes underneath the
Figure 9.4. Location of implants.