Drop centering device

Abstract

A variable-focus lens that includes a wall made of an insulating material, a drop of an insulating liquid arranged on an area of a first surface of the wall, a conductive liquid covering the first surface and the drop, and an electrode arranged on a second surface of said wall. The insulating and conductive liquids are non-miscible, having different optical indexes and substantially the same density. The drop of the variable-focus lens is centered in a truncated cone centered on an axis perpendicular to the first surface, the bottom of which is pierced with a centered hole, and the insulating material wall is transparent and covers the hole.

1 . An optical element having an optical axis, comprising:
 a chamber having a side surface and a bottom surface;   a first liquid and a second liquid contained in said chamber; and   an electrode insulated from said first liquid and said second liquid, said electrode being placed against at least one of the side surface or the bottom surface of said chamber;   wherein said first liquid and second liquid are immiscible and form an optical dioptre.   
     
     
         2 . The optical element of  claim 1 , wherein the dioptre contacts the side surface of said chamber. 
     
     
         3 . The optical element of  claim 1 , wherein the side surface of said chamber is arranged at an angle with respect to the optical axis 
     
     
         4 . The optical element of  claim 1 , wherein the side surface of the chamber comprises a wall made of an insulating material. 
     
     
         5 . The optical element of  claim 1 , wherein the bottom surface of said chamber is planar. 
     
     
         6 . The optical element of  claim 1 , wherein the bottom surface of said chamber is convex. 
     
     
         7 . The optical element of  claim 1 , wherein the bottom surface of said chamber is concave. 
     
     
         8 . The optical element of  claim 1 , wherein the optical element is a variable-focus lens. 
     
     
         9 . The optical element of  claim 1 , wherein the bottom surface of said chamber and the dioptre form a plano-convex lens. 
     
     
         10 . The optical element of  claim 1 , wherein the bottom surface of said chamber and the dioptre form a bi-convex lens. 
     
     
         11 . The optical element of  claim 1 , wherein the bottom surface of said chamber and the dioptre form a meniscus lens. 
     
     
         12 . The optical element of  claim 1 , wherein the optical element is part of an optical system comprising an alternating current voltage source. 
     
     
         13 . The optical system of  claim 12 , wherein the alternating current voltage source has a frequency range between 100 and 10 000 Hz. 
     
     
         14 . A method of changing the focus of a variable focus lens comprising an optical element and an alternating current voltage source,
 wherein the optical element comprises an optical axis, and   includes a chamber having a side surface comprising a wall made of an insulating material and a bottom surface, a first liquid and a second liquid contained in said chamber, and   an electrode insulated from said first liquid and said second liquid, said electrode being placed against at least one of the side surface or the bottom surface of said chamber, wherein said first liquid and second liquid are immiscible and form an optical dioptre, the method comprising:   selectively applying a voltage differential between the first liquid and the wall sufficient to change the wettability of the first liquid with respect to the wall to change the shape of the body of the first liquid; and   using the change in the shape of the body of the first liquid to change the shape of the dioptre between the first and second liquids.   
     
     
         15 . The method of  claim 14 , wherein the alternating current voltage source has a frequency range between 100 and 10 000 Hz. 
     
     
         16 . A method of changing the focus of a variable focus lens, the method comprising:
 providing a variable focus lens having an optical axis, and comprising:
 a chamber having a side surface and a bottom surface, said chamber comprising an wall made of an insulating material; 
 a first conducting liquid and a second insulating liquid contained in said chamber; and 
 an electrode insulated from said first conducting liquid and said second insulating liquid, said electrode being placed against at least one of the side surface or the bottom surface of said chamber; 
 wherein said first conducting liquid and second insulating liquid are immiscible and form an optical dioptre; 
   providing an AC voltage source; and   selectively applying a voltage differential between the first conductive liquid and the wall sufficient to change the wetability of the first conducting liquid with respect to the wall to change the shape of the body of the first conductive liquid; and   using the change in the shape of the body of the first conductive liquid to change the shape of the dioptre between the first and second liquids.   
     
     
         17 . A method of  claim 16 , wherein the alternating current voltage source has a frequency range between 100 and 10 000 Hz.