Variable focus lens having two liquid chambers

#The invention relates to a variable focus lens having a first and a second chamber filled with liquids having different indices of refraction. The two chambers are separated by a primary membrane. The lens comprises a housing and an actuator. An axial movement of the actuator with respect to the housing causes the primary membrane to be deformed.

#The invention also relates to a method for manufacturing such a lens.

#A lens of this type is shown in WO 2008/020356. The lens has two hermetically sealed chambers filled with different liquids of differing refractive indices but with similar density. The chambers are separated by a deformable membrane. An advantage of this design lies in the reduction of membrane deformations caused by gravity. However, the design described in WO 2008/020356 requires an indirect force transmission through a magnetic field to the membrane because the actuator is not readily accessible. In addition, manufacturing this type of lens is difficult. In particular, it has been found to be difficult to remove residual air from the chambers.

#The invention will be better understood and objects other than those set forth above will become apparent when consideration is given to the following detailed description thereof. Such description makes reference to the annexed drawings, wherein:

#FIG. 1 shows a sectional, perspective view of a first embodiment of a variable focus lens,

#FIG. 2 shows a sectional, perspective view of a second embodiment of a variable focus lens, and

#The term “radial” is understood to designate a direction perpendicular to the optical axis of the lens.

#The term “axial” is understood to designate a direction parallel to the optical axis of the lens.

#The terms “rigid” and “flexible” are used in relation to each other. The membranes of the lens are by at least one order of magnitude more flexible and less rigid than the housing and the actuator.