Bionic eye

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Bionic eye

  1. 1. MT5009 BIONIC EYES Ler Ming Lim A0098570U Coline Michele Juin A0104445N Ka Mung Chee A0098573M Hanisah Hannifah Gupta A0098462U Kah Heng Cheng A0082075H Gary Ho Wai Chi A0082062N For information on other new technologies that are becoming economically feasible, see http://www.slideshare.net/Funk98/presentations
  2. 2. Presentation Outline 1. How it works 2. Important technological components i. Electrodes implanted on the eye ii. Camera Sensor Technology iii. Video processing unit/Interface to the brain (light-> electrical signals) iv. Radio transmitter/antenna 3. Important dimensions of performance i. surgery time, overall factors 4. Important dimensions of overall cost 5. Improvements/Future opportunities
  3. 3. How a Human eye works
  4. 4. Common Vision Problems • Problems with the eyes • Structural • Solved with corrective eyewear/eye surgery • Retina / macula => affects light processing functions • Cannot be solved with correcive eyewear/surgery • Bionic eye? No cure
  5. 5. Types of Visual Prostheses Based on neuronal electrical stimulation at different locations along the visual pathway • cortical • optic nerve • epiretinal • subretinal Retinal prosthesis is the most advanced visual prosthesis to date
  6. 6. ARGUS II – Most Advanced Retinal Prosthesis ARGUS II epiretinal implant  largest study of a retinal prosthesis more than 60 subject years of implant experience with this device only FDA-approved study  only retinal implant to get a CE mark to be sold as a medical device in Europe Developed by Second Sight Medical Products Inc http://www.youtube.com/watch?featur e=player_detailpage&v=Bi_HpbFKnS w
  7. 7. Argus II- How does it work? Source/ http://youtu.be/Bi_HpbFKnSw
  8. 8. Argus II - How does it work?
  9. 9. What Do Users See? Source: NY Times, Device Offers Partial Vision for the Blind
  10. 10. Components of Bionic Eye Camera Video Processor Wireless Electrodes
  11. 11. Component: Camera Sensor Technology Camera
  12. 12. Camera Image Sensor Technology • CMOS Image Sensor has photo diodes (PD), same as CCD Image Sensor. But there is difference in the mechanism of transmitting electrons. • CMOS transmit electrons using the wire; • Charged Coupled Device aka CCD itself. • The colored elements in the figure correspond the pixels; In color cameras, they are usually filtered red, blue and green.
  13. 13. Monochrome (1-bit) 2-bit Grayscale 4-bit Grayscale 8-bit Grayscale Monochrome Palettes
  14. 14. Camera Module Scaling Sources: http://image-sensors-world.blogspot.sg/2011/11/st-published-its-tsv-camera-module.html http://www.chicony.com.tw/products/cm_module/cm.html
  15. 15. Component: Video processing unit Video Processor
  16. 16. Video-processing process Example of 4*4 matrix of electrode Current prosthetics use electrodes of optogenetic transducers to allow users to perceive, as most, "spots of light or high-contrast edges.“ 1 Source: 1) Journal Proceedings of the National Academy of Sciences. Step 1: simplify the image => making just black and white Step 2: reduce that image to the number of electrode available
  17. 17. Video processor will benefit from IC/SOC improvement • As discussed in Lectures, improvements in: • Costs • Performances, respond time (need to be real time) • Size • Power consumption Sources: “Bionic eyes”, Anonymous, The Futurist; Sep-Oct 1993; 27, 5; ProQuest, pg. 53 Example of decrease in size: From Argus II to Multi-unit Artificial Retina Chipset (photosensing, processing, and stimulating chip , 2mm * 2mm)
  18. 18. Improvement of video processing Original image Image (reconstructed) for a blind retina Standard Optogenetic prosthetic Encoder-ChR2 prosthetic Source: “Retinal prosthetic strategy with the capacity to restore normal vision” Sheila Nirenberg1 and Chethan Pandarinath
  19. 19. Component: Wireless transmission Wireless
  20. 20. Wireless transmission of Image + Power Source: Building the bionic eye: an emerging reality and opportunity, Lotfi B. Merabet (2011)
  21. 21. Planned Changes to Marketed Version of the Systems Planned Changes: • Edge of coil suture tab rounded slightly • Changed the radio frequency at which the glasses communicate to meet new international radio communication standards • Modified the implant chip to improve wireless efficiency • Externals modified to improve ergonomics and ease of programming Source: INTRAOCULAR RETINAL PROSTHESIS, BY Mark S. Humayun, MD, PhD (2011)
  22. 22. Key Performance Factor • Surgical Consideration • Feature size • Wireless speed, Penetration • Data integrity
  23. 23. 512-Channel Intraocular Epiretinal Implant Technologies Basic Methods of Improvement Parylene Flex Technology. IC chip •Scale down thanks to high-density multi-channel integration chip •Improve wireless penetration and data integrity •Low cost (wafer size scale up) 3-coil wireless power transfer and data coil interference system •High signal processing power •High efficiency up to 36.5% •Improve safety margin for surgical consideration Source: PACKAGING STUDY FOR A 512-CHANNEL INTRAOCULAR EPIRETINAL IMPLANT, Jay Han-Chieh Chang (2012)
  24. 24. High-Density Multi-channel Chip Integration - Parylene Flex Technology Fabrication process of the Parylene- C flexible circuit board. Process flow of conductive epoxy squeegee technique to make electrical and mechanical connections between Parylene flex and chips Source: PACKAGING STUDY FOR A 512-CHANNEL INTRAOCULAR EPIRETINAL IMPLANT, Jay Han-Chieh Chang (2012)
  25. 25. 3 Coil Wireless Power Transfer and Data Coil Interference The 3-coil scheme for inductive power transfer. A model of the coil system is built using HFSS for the coil interference analysis Source: PACKAGING STUDY FOR A 512-CHANNEL INTRAOCULAR EPIRETINAL IMPLANT, Jay Han-Chieh Chang (2012)
  26. 26. Component: Microelectrode Array Electrodes
  27. 27. Microelectrode Array -Electrode is implanted in the inner surface of retina -Conductive tips of each electrode reside in the ganglion cell layer - Electrodes are made by MEMs
  28. 28. Key Performance Factors Resolution Electrode-retina interface performance Material biocompatibility & Stability
  29. 29. Resolution & Pixel size Better vision with smaller pixel size Source: Photovoltaic Retina Prosthesis for restoring sight to the blind, Daniel Palanker (2012)
  30. 30. How the eye sight looks, 300um Source: Photovoltaic Retina Prosthesis for restoring sight to the blind, Daniel Palanker (2012)
  31. 31. How the eye sight looks, 30um Source: Photovoltaic Retina Prosthesis for restoring sight to the blind, Daniel Palanker (2012)
  32. 32. How the eye sight looks, 30um Source: Photovoltaic Retina Prosthesis for restoring sight to the blind, Daniel Palanker (2012)
  33. 33. How the eye sight looks, 10um Source: Photovoltaic Retina Prosthesis for restoring sight to the blind, Daniel Palanker (2012)
  34. 34. How the eye sight looks, 3um Source: Photovoltaic Retina Prosthesis for restoring sight to the blind, Daniel Palanker (2012)
  35. 35. No. of electrodes have Improved Made possible by reduction in scale in MEMs manufacturing Normal vision = more than one hundred million receptors in each eye Source: The Artificial Retina Progress Report, Craig Blackwell MD (2011)
  36. 36. Are there Physical Limits to Electrode size? • optimal size of an electrode should be comparable to the cellular size (L ≈ 10 μm), i.e. its radius ro should be about 5μm. Electrode • Charge transfers- changes of the electrodes from positive to negative- flow of electrons into the tissue Source: Electrode-cellular interface. Science .10 April 2009. Vol 324 )
  37. 37. Distance of Electrode to Cells • Distance between electrode and retina is most critical! • Large distance requires high charge for stimulation • Causes heating of the tissue Source: Electrode-cellular interface. Science .10 April 2009. Vol 324 )
  38. 38. Improvement in MEMs Technology 1. 3D Geometry • Pillar electrode arrays • Penetrating electrodes 2. Coating to improve electrochemical performance • Polymer coating http://neurotechzone.com/posts/292 Source: Conducting polymers for neural interfaces: Challenges in developing an effective long-term implant. Biomaterials Volume 29, Issues 24–25, August–September 2008, Pages 3393–3399
  39. 39. Better Materials for Micro-electrode Arrays Traditional New Material Metal electrodes (Ir, Pt or Au) Nanocrystalline diamond Charge Transfer Passive, good conductor Good conductor Contact to neurons Not Optimal, may cause electrode degeneration Good biocompatibility and bio stability Does not get degraded 3D shaped mechanically flexible diamond microelectrode arrays for eye implant applications: The MEDINAS project E - The Development of a Retinal Prosthesis: A Significant Biomaterials Challenge
  40. 40. Improvements and future opportunities
  41. 41. Entrepreneurial Opportunities US $150,000 4 hours of surgery Black & White Vision Improve Resolution Performance Improve Other Vision Problems
  42. 42. 0 200 400 600 800 1000 1200 2000 2010 2020 NumberofElectrodes Year Electrode trend Argus I Argus II Bionic Vision Australia, Wide View Device Bionic Vision Australia, High Acuity Device Improvements in Resolution Performance Source: Bionic Vision Australia, Argus websites
  43. 43. Improvements in Cost $0 $50,000 $100,000 $150,000 $200,000 2013 2015 2020 2030 Cost Projection of Bionic Eye Estimated Cost Breakdown Camera Electrode Video Processor Wireless Source: McKinnon, B. J. (2013), Cochlear implant programs: Balancing clinical and financial sustainability. The Laryngoscope, 123: 233–238. doi: 10.1002/lary.23651
  44. 44. Potential Applications of this technology/ Future Opportunities http://youtu.be/iUz1ScDKslk Source: http://youtu.be/iUz1ScDKslk
  45. 45. Any Questions?

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