Patent ID: 7553020
Filing Date: 2009-06-30
Classification: A61B

Abstract:
1. A medical diagnostic instrument comprising: an illuminating system for providing illuminating light; an imaging system for directing said illuminating light to a target and for transmitting light reflected from said target to a viewing location; wherein said imaging system includes an electrically controllable variable focus liquid lens assembly for focusing said light reflected from said target at said viewing location; and wherein said liquid lens assembly includes first and second spaced liquid lenses; and wherein each of said first and second liquid lenses includes a housing filled with a first liquid, and a drop of a second liquid being in contact with said first liquid in a predetermined form, the first and second liquids being immiscible, of different optical indexes, and of substantially same density; wherein the first liquid is conductive and the second liquid is insulating; and wherein each of said lenses further include a first electrode insulated from said second liquid and a second electrode in electrical contact with said first liquid; and a variable voltage control for selectively applying a voltage to said first and second electrodes to vary the focal length of each of said lenses; and including a variable iris located between said first and second liquid lenses.