Systems and Methods for Power Management of Implantable Ophthalmic Devices

A method of charging a battery, the method comprising:

• charging the rechargeable battery for a first time interval using a first constant current;
• determining that a voltage of the rechargeable battery exceeds a first threshold value;
• charging the rechargeable battery for a second time interval using a second constant current less than the first constant current;
• determining that the voltage of the rechargeable battery exceeds a second threshold value;
• and
• charging the rechargeable battery for a third time interval using a constant voltage.

An intraocular optic comprising:

• an electro-active element configured to vary at least one optical characteristic of the intraocular optic;
• a sensor configured to generate a sensor signal within less than about 100 milliseconds in response to sensing at least one of a change in light level and a physiological response;
• a first control circuit, operably coupled to the sensor, configured to sample the sensor signal and to generate an actuation signal within 100 milliseconds of sampling the sensor signal in response to the sensor signal;
• a second control circuit, operably coupled to the first control circuit and to the electro-active element, configured to:
• (i) receive the actuation signal,
• (ii) transition from a low-power state to a high-power state and actuate the electro-active element within about 5 milliseconds of receiving the actuation signal so as to vary the at least one optical characteristic of the intraocular optic in response to the actuation signal, and
• (iii) transition from the high-power state to the low-power state within about 5 milliseconds of actuating the electro-active element so as to minimize current leakage from the second control circuit.

A method of altering at least one optical characteristic of an intraocular optic in response to at least one of a change in light level and a physiological response, the method comprising:

• (A) sensing the at least one of the change in light level and the physiological response;
• (B) generating a sensor signal within about 100 milliseconds of sensing the at least one of the change in light level and a physiological response;
• (C) sampling the sensor signal with a first control circuit;
• (D) generating an actuation signal, with the first control circuit, within 100 milliseconds of sampling the sensor signal;
• (E) actuating the intraocular optic based on the actuation signal so as to minimize current leakage from the second control circuit;
• (F) receiving the actuation signal at a second control circuit;
• (G) transitioning the second control circuit from a low-power state to a high-power state in response to the actuation signal;
• (H) actuating an electro-active element with the second control circuit so as alter the at least one characteristic of the intraocular optic within about 5 milliseconds of receiving the actuation signal;
• and
• (I) transitioning the second control circuit from the high-power state to the low-power state within about 5 milliseconds of actuating the electro-active element so as to minimize current leakage from the second control circuit.

An implantable device comprising:

• a first rechargeable battery having a first voltage;
• a second rechargeable battery having a second voltage;
• and
• a processor, operably coupled to the first rechargeable battery and the second rechargeable battery, configured to iteratively:
• determine that the first voltage has fallen below the second voltage;
• select the second rechargeable battery to discharge in response to the determination that the first voltage has fallen below the second voltage;
• determine that the second voltage has fallen below the first voltage;
• and
• select the first rechargeable battery to discharge in response to the determination that the first voltage has fallen below the second voltage.

An intraocular implant comprising:

• a sensor configured to sense at least one of a light level and a physiological response;
• an electro-active element to vary at least one optical characteristic of the intraocular implant;
• a first control circuit, operably coupled to the sensor, configured to sample the sensor signal and to generate an actuation signal within 100 milliseconds of sampling the sensor signal in response to the sensor signal;
• a second control circuit, operably coupled to the first control circuit and to the electro-active element, configured to:
• (i) receive the actuation signal,
• (ii) transition from a low-power state to a high-power state and actuate the electro-active element so as to vary the at least one optical characteristic of the intraocular optic in response to the actuation signal, and
• (iii) transition from the high-power state to the low-power state of actuating the electro-active element so as to minimize current leakage from the second control circuit;
• and
• at least one rechargeable battery, operably coupled to the first control circuit and the second control circuit, configured to provide power to the second control circuit when the second control circuit is in the high-power state and to be recharged by:
• (i) a first constant current provided by the first control circuit over a first time interval,
• (ii) a second constant current less than the first constant current provided by the first control circuit over a second time interval after the first time interval, and
• (iii) a constant voltage provided by the first control circuit over a third time interval after the second time interval.