Abstract: A method for calibration in the field of imaging systems and imaging systems using the method for calibration. In particular, the method involves calibration in the field of open loop variable focus imaging systems and methods for calibration in the field of imaging system having a variable optical parameter.

Abstract: The invention concerns an optical lens comprising a cavity formed by two transparent windows and a peripheral frame positioned in between, said cavity containing first and second liquids, non miscible, forming an interface, said interface being movable by electrowetting on a wall of said peripheral frame by application of a voltage between first and second electrodes, wherein said wall has a non symmetrical revolution surface, the geometrical shape of which is calculated such that said interface is of a predetermined shape, for example substantially spherical, for at least one value of said voltage.

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.

Abstract: The invention relates to a variable-focus lens comprising two opposing walls (21, 22) which are orthogonal to the axis of the lens and which define a space containing an isolating liquid (31) on the first wall (22) and a conductive liquid (32) which covers the isolating liquid and which comes into contact with the second wall (21). The surface (24) of the first wall (22) has high wettability for the isolating liquid and low wettability for the conductive liquid, while the surface (23) of the second wall (21) has high wettability for the conductive liquid and low wettability for the isolating liquid.

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.

Abstract: A method for centering a drop of liquid on a given point on a surface. The inventive method consists in forming a bell-mouthed recess, whereby said recess has a curvature at any point at the limit of contact between the drop and the recess that is lower than or opposite to the curvature of a circle (TC) that is tangent to the surface of the recess to said point and at a symmetrical point (CP2) of said surface.

Abstract: A lens assembly of variable focal length comprises two transparent plates (24, 38) at least partially facing each other and parallel to one another and delimiting, at least in part, an internal volume (15) containing two non-miscible liquids having different optical indices. The lens comprises an elastic element (36) capable of deforming in response to a change in pressure of the liquids, in such a way as to substantially maintain the optical properties of the lens assembly, e.g., in order to maintain the parallelism of the two transparent plates.

Abstract: The invention relates to a variable-focus lens (60) for focusing light rays in light paths passing through the lens along an optical axis (?). The lens comprises an arrangement of first and second immiscible liquids (67, 68) that have different refractive indices and are in contact over a moveable refractive optical interface (69), a volume of gas (72) in contact with one of said liquids, and a retention measure (70, 74) for keeping the volume of gas away from the light paths of the light rays passing through the lens for focusing.

Abstract: The present invention relates to a method of manufacturing an electrowetting-based variable-focus lens, comprising: (a) providing an enclosure having a cavity (17) and at least one channel (27, 28; 59) communicating at one end with the cavity and at the other end emerging at the exterior surface of the lens; (b) filling the cavity with first and second liquids (44, 47) that are immiscible and of different refractive indices via the channel; and (c) hermetically scaling the channel.

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.

Abstract: A method for centering a drop of liquid (2) on a given point on a surface (4). The inventive method consists in forming a bell-mouthed recess (6), whereby said recess has a curvature at any point at the limit of contact between the drop and the recess that is lower than or opposite to the curvature of a circle (TC) that is tangent to the surface of the recess to said point and at a symmetrical point (CP2) of said surface.

Abstract: The present invention concerns a method for controlling a variable focal length lens (10) comprising a dioptre (28) capable of being deformed by variation of the electro-wetting characteristics by application of a control voltage (V), wherein a focal length value corresponds to a given control voltage in the steady state, said method comprising: —applying, during a transition between the application of a first control voltage (V1) corresponding to a first focal length value (f1) and a second control voltage (V2) corresponding to a second focal length value (f2), a control voltage which is different from the first and second control voltages and changes according to a given profile that depends on the first and second control voltages.

Abstract: A method for centering a drop of liquid on a given point on a surface. The inventive method consists in forming a bell-mouthed recess, whereby said recess has a curvature at any point at the limit of contact between the drop and the recess that is lower than or opposite to the curvature of a circle (TC) that is tangent to the surface of the recess to said point and at a symmetrical point (CP2) of said surface.

Abstract: The invention relates to a variable-focus lens (60) for focussing light rays in light paths passing through the lens along an optical axis (?). The lens comprises an arrangement of first and second immiscible liquids (67, 68) that have different refractive indices and are in contact over a moveable refractive optical interface (69), a volume of gas (72) in contact with one of said liquids, and a retention measure (70, 74) for keeping the volume of gas away from the light paths of the light rays passing through the lens for focussing.

Abstract: A lens assembly of variable focal length comprises two transparent plates (24, 38) at least partially facing each other and parallel to one another and delimiting, at least in part, an internal volume (15) containing two non-miscible liquids having different optical indices. The lens comprises an elastic element (36) capable of deforming in response to a change in pressure of the liquids, in such a way as to substantially maintain the optical properties of the lens assembly, e.g., in order to maintain the parallelism of the two transparent plates.

Abstract: A method for centering a drop of liquid on a given point on a surface. The inventive method consists in forming a bell-mouthed recess, whereby said recess has a curvature at any point at the limit of contact between the drop and the recess that is lower than or opposite to the curvature of a circle (TC) that is tangent to the surface of the recess to said point and at a symmetrical point (CP2) of said surface.

Abstract: A variable focus lens comprising a chamber (12) filled with a first liquid (13), a drop of a second liquid (11) being disposed at rest on a region of a first surface of an insulating wall of the chamber, the first and second liquids being non miscible, of different optical indexes and of substantially same density. The first liquid is conductive and the second liquid is insulating. The lens further comprises means for applying a voltage between the conductor liquid and an electrode (16) placed on the second surface of said wall; and centering means for maintaining the centering of the edge of the drop while the voltage is applied and for controlling the shape thereof.

Abstract: A variable focus lens comprising a chamber (12) filled with a first liquid (13), a drop of a second liquid (11) being disposed at rest on a region of a first surface of an insulating wall of the chamber, the first and second liquids being non miscible, of different optical indexes and of substantially same density. The first liquid is conductive and the second liquid is insulating. The lens further comprises means for applying a voltage between the conductor liquid and an electrode (16) placed on the second surface of said wall; and centering means for maintaining the centering of the edge of the drop while the voltage is applied and for controlling the shape thereof.