Patent ID: 7813048

Claim:
A circuit for supplying a drive voltage to an electroactive lens, comprising: an input terminal for coupling to a low voltage direct current supply; an output terminal for coupling to said electroactive lens; a high voltage power supply for producing a DC output, said high voltage power supply including a plurality of charge pump circuits coupled between said input terminal and said output terminal; and a switching circuit coupled to said output terminal for alternating polarity of said DC output at said output terminal; wherein each charge pump of the plurality of charge pump circuits comprises: a first diode having a first terminal coupled to a first output of said charge pump circuit for preventing discharge of said first output; a first capacitor having a first terminal coupled to a first phase of a clock and further having a second terminal coupled to a second terminal of said first diode for charging said output through said first diode; a second diode having a first input coupled to said second terminal of said first diode; and a second capacitor having a first terminal coupled to a second phase of a clock input and further having a second terminal coupled to a second output of second diode.