Patent ID: 8451525

Claim:
An optical apparatus comprising: a sealing case extending along and about an optical axis defining an optical axis direction and having a centrally-disposed partition wall having a partition wall thickness extending in a thickness direction being perpendicular to the optical axis direction and dividing the sealing case into a plurality of generally equally-sized chambers the optical axis extending through the partition wall thickness; a polar liquid having polarity and a nonpolar liquid having no polarity which are respectively sealed in each of the chambers; and a plurality of electrodes pulling the polar liquid by an electrowetting phenomenon upon application of a driving voltage, the plurality of electrodes including a central pair of electrodes and at least two peripheral pairs of electrodes, respective ones of the central pair of electrodes and the at least two peripheral pairs of electrodes being spaced apart from one another along the optical axis direction and being facially opposed to one another, the central pair of electrodes being disposed generally centrally between or among the at least two peripheral pairs of electrodes and being associated with each of the chambers, wherein one of the polar liquid and the nonpolar liquid is colored with a color having a light-blocking property, and the other has a light-transmitting property, at least a part of the partition wall is positioned in an optically effective space extending along and radially about the optical axis with the central pair of electrodes extending radially from and generally surrounding the optical axis to sandwich the optically effective space therebetween, and when a driving voltage is applied to the pair of central electrodes, the polar liquid moves away from the at least two peripheral pairs of electrodes and inwardly towards the central pair of electrodes to occupy the optically effective space and, when the driving voltage is applied to the at least two peripheral pairs of electrodes, the polar liquid moves outwardly away from the central pair of electrodes and outwardly towards the at least two peripheral pairs of electrodes to vacate the optically effective space.