Research progress of subretinal implant based on electronic stimulation / 生物医学工程学杂志

ABSTRACT

Subretinal prosthesis is one kind of retinal prosthesis, which means that a microimplant based on MEMS technology is inserted in the subretinal space to stimulate the optic nerve and elicit an electrical-evoked response on the cortical region. The subretinal implant is made up of extraocular part and intraocular part. As an important part, the latter consists of accessorial setting and stimulation chip that contains microphotodiode array (MPDA) and microelectrodes. The paper main body is made up of four parts. Firstly significance of the retinal prosthesis is given out; secondly fundamentals on both in retina physiology and retinal prosthesis theory are introduced simply. Then the key segment about the subretinal microimplant is presented in detail. In the third segment, first of all is its design concept, the second is fabrication of MPDA which consists of several parts. First is microscopic configuration, electric prototype schematic and chip image CMOS. The second is detailed fabrication flow with several special materials. Then is situation of its dimension. The fourth segment presents challenge and outlook.