BIONIC EYE POWERED BY NANOGENERATOR

Design of Artificial Electronic EyePraveen Kumar Narayanan(Final year , EIE Department)

Guhan Senthil (Final year , ECE Department )

Panimalar Engineering CollegeChennai, Tamilnadu,India.

Causes of BlindnessDamages to clear structures in the eye, that allow the light to pass throughDamages to the nerves within the eyeDamages to the Optic NerveDamages to the Brain

BIONIC EYEBiological - Electronic EyeElectronic Device which replaces the functionality of part or whole of the human eye Intended to restore the lost vision or amplify the existing visionBionic eye system is basically divided into two different approachesThe First approach is the MARC systemThe Second approach is the ASR system

MARC Multiple Unit Artificial Retina ChipsetThe images are captured by an external cameraProcessed and then transmitted to an implant on the retina.This in-turn will transmit it to the ganglion cells and then to the optic nerve Requires External Power Supply

ASR Artificial Silicon Retina

A retina is simulated on siliconThe basic blueprint for this is the human eye itselfThe Silicon retina is implanted in the eye No external devices required

Multiple Unit Artificial Retina Chipset System (MARC)

IMPLANT STRUCTURELayers1- Photodiode Array2- Polyimide strip3- Stimulator chip

Camera inputCamera image is processed and converted to electric signals by the image processorFrom image processor ,signals hits photodiode array of implant via the transmitter and receiverThis in turn powers the stimulator chip (SC)

The MARC System requires an external battery power supply which should be carried by the patient .

BATTERY

Working of the ASR SYSTEMThe ASR is a bio compatible chip with an array of photoreceptors

Silicon Chip drives current to electrodes facing the retina

This excites the ganglion cells -> axons -> optic nerve -> visual cortex in occipital lobe of brain

Brain helps in perceiving the image

Approaches Towards ImplantationEpiretinal Approach involves a semiconductor based device positioned on the surface of the retina to try to simulatethe remaining overlying cells of the retina.

Sub retinal Approach involves implanting the ASR chip behind the retina to simulate the remaining viable cells.

Limitations Of ASRsASR is designed to interface and function with the retina that has partial outer retinal degeneration.

ASR can be applied only when the photoreceptor cellular layer of the retina is damaged but the remaining cellular layers are still functional.

Light is the source of energy for ASR to get activated.If there is no light entering the eye, then the system does not work

Artificial corneal transplant methodology lens replacement

Very Small Camera placed on a small circular printed circuit board

Processor circuit is embedded on to the PCB board

The Printed Circuit Board is placed in between the lenses in the corneal part of the eye

Power Source is obtained from Nano generators

Bio compatible lenses

Replacing the corneal part of the human eye

The lenses are placed one behind the other and then placed in the eye

The PCB is placed in between the corneal lenses

Size lesser than one cent coin of Canada

Consists of a small camera and processor

Placed in between the artificial corneal lenses

The electric signals from PCB are sent to the retinal implant by thin bio compatible wire

Based on Piezoelectric effect Zinc Oxide material wires usedMaximum power produced 3 vDeveloped by Doctor Yong Shi and team

The Nano generators are placed on the surface of blood vesselsWith the pressure of the blood flow on the blood vessel surface, power is producedPower generated is supplied to the Bionic eye system

One of the major limitations of current active implantable biomedical devices is that they arebatterypowered. This means that they either have to be recharged or replaced periodically. Dr. Shis group has demonstrated a technology that will allow implantable devices to recover some of the mechanical energy in flowing blood or peristaltic fluid movement in the GI tract to power smart implantable biomedical devices, -Dr. Arthur Ritter, Director of Biomedical Engineering,Stevens Institute of Technology, NewJersey,USA.

The overall bionic eye system becomes compact

No external wiring to the body

Size of the power source is reduced

Life time of the battery increases

Best suitable for patients suffering from both corneal infections and retinal degeneration

Complex Surgical methods are the only disadvantage

THANK YOU

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