Video processing unit for a visual prosthetic apparatus

1. A video processing unit configured to convert a video image to stimulation patterns for stimulating neural tissue in a subject's eye, the video processing unit comprising:

a video processor for converting a video image to a digital video stream;

a memory for storing the digital video stream;

a video preprocessor data interface for forming stimulation patterns based on the stored digital video stream; and

a voltage and current monitoring circuit configured to monitor the integrity status of a retinal stimulation system by sampling and monitoring current and voltage of an RF transmitter.

2. The video processing unit of claim 1 , wherein the video processing unit further comprises a power supply distribution and monitoring circuit for generating appropriate voltages and adjusting power level of the stimulation patterns transmitted to a retinal stimulation system.

3. The video processing unit of claim 2 , wherein the power supply distribution and monitoring circuit is configured to turn off the video processing unit if the power from a battery providing energy to the video processing unit drops below a predetermined level.

4. The video processing unit of claim 3 , wherein the predetermined level is about 6.75 volts.

5. The video processing unit of claim 1 , wherein the video processing unit further comprises a reset circuit for resetting the video processing unit.

6. The video processing unit of claim 5 , wherein the reset circuit resets the video processing unit based on manual push-button reset, watchdog timer expiration or firmware based shutdown.

7. The video processing unit of claim 1 , wherein the video processing unit further comprises a digital signal processor for communicating with the video processor, the memory and the video preprocessor data interface.

8. The video processing unit of claim 7 , wherein the video processing unit further comprises a system main clock for the digital signal processor.

9. The video processing unit of claim 7 , wherein the video processor comprises:

an I 2 C protocol controller configured to convert parallel bus interface of the digital signal processor to I 2 C protocol bus or vice versa.

10. The video processing unit of claim 1 , wherein the video processor comprises:

a video decoder for converting the video image into a high-resolution digitized image; and

a video scaler for scaling down the high-resolution digitized image to the digital video stream.

11. The video processing unit of claim 10 , wherein the video decoder comprises:

an analog input processing circuit;

a chrominance and luminance processing circuit; and

a brightness contrast and saturation control circuit.

12. The video processing unit of claim 10 , wherein the video scaler comprises;

an acquisition control circuit;

a pre-scaler circuit;

a brightness contrast and saturation control circuit; and

line buffer and output interface.

13. The video processing unit of claim 1 , wherein the video processor comprises:

a forward telemetry controller forming a forward telemetry frame for a retinal stimulation system; and

a back telemetry controller decoding backward telemetry frame from the retinal stimulation system.

14. The video processing unit of claim 1 , wherein the video processor comprises:

a parallel flash memory to store executable code; and

a serial flash memory to store data.

15. The video processing unit of claim 1 , wherein the video processor comprises:

a digital signal processor configured to apply digital filtering algorithms to the video image; and

a general-purpose micro-controller configured to provide real-time control of voltage to an RF circuit or configured to control a user interface.

16. A method for providing artificial vision, the method comprising:

capturing a video image;

converting the video image to a digital video stream;

storing the digital video stream;

forming stimulation patterns based on the stored digital video stream; and

stimulating neural tissue in a subject's eye based on the stimulation patterns.

17. The method of claim 16 , further comprising:

generating appropriate voltages and adjusting power level of the stimulation patterns.

18. The method of claim 16 , further comprising turning off power if the power from a battery drops below a predetermined level.

19. The method of claim 18 , wherein the predetermined level is about 6.75 volts.

20. The method of claim 16 , further comprising:

converting the video image into a high-resolution digitized image; and

scaling down the high-resolution digitized image to the digital video stream.

21. The method of claim 16 , further comprising:

forming a forward telemetry frame for stimulating neural tissue in the subject's eye.

22. The method of claim 16 , further comprising:

storing executable code in parallel flash memory; and

storing data in a serial flash memory.