×

Method and apparatus to provide safety checks for neural stimulation

  • US 8,423,151 B2
  • Filed: 10/28/2007
  • Issued: 04/16/2013
  • Est. Priority Date: 04/28/2006
  • Status: Active Grant
First Claim
Patent Images

1. A method of stimulating retinal neural tissue comprising:

  • providing a neural stimulator including a plurality of electrodes suitable to stimulate retinal neural tissue;

    providing a biphasic square wave pulse to each electrode;

    calculating capacitive impedance by a first derivative of the voltage across a stimulation pulse;

    testing the impedance of all electrodes by obtaining voltage measurements from all electrodes in response to said square wave pulses;

    recording changes of capacitive impedance over time derived from said voltage measurements; and

    determining lifting of electrodes based on changes of a capacitive component of said impedance by considering phase shifts in said changes of impedance over time;

    wherein the changes of the capacitive component are computed based on a phase difference derived from a difference between a resultant voltage waveform obtained from the voltage measurements and a baseline voltage waveform without phase shifts derived from said voltage measurements.

View all claims
  • 3 Assignments
Timeline View
Assignment View
    ×
    ×