Patent ID: 8547643

Claim:
An optical element comprising: a container having a holding chamber; a first liquid filled in the holding chamber; a second liquid filled in the holding chamber and not mixing with the first liquid; first and second electrodes for applying an electric field to the first liquid; and voltage application means for applying a voltage between the first electrode and the second electrode, wherein a change of a position subject to the voltage application by the voltage application means to the first and second electrodes moves the first liquid and the second liquid within the holding chamber, the holding chamber has an adjustment chamber for adjusting an amount of transmitted light based on a presence of the first liquid and multiple lay-by chambers connecting to the adjustment chamber, the adjustment chamber and the multiple lay-by chambers have first and second end walls facing against each other in a direction that light passes through, the first electrode is provided on one end wall of the first and second end walls of the adjustment chamber and multiple lay-by chambers, the first electrode including a single electrode member extending across one end wall of the first and second end walls of the adjustment chamber and multiple lay-by chambers, and the second electrode is provided on the other end wall of the first and second end walls, the second electrode including multiple electrode members provided separately on the other end wall of the first and second end walls of the adjustment chamber and multiple lay-by chambers, wherein each electrode member of the second electrode is adjacent to at least one other electrode member, each electrode member having pits and projections at a location proximate the at least one other electrode member, the pits and projections of the adjacent electrode members being spaced apart from and facing against each other, wherein each electrode member proximate the end walls of the adjustment chamber have larger projections toward the end walls of the lay-by chambers than the other projections of the electrode member, wherein each electrode member proximate the end walls of the lay-by chambers have larger pits toward centers of the lay-by chambers than the other pits of the electrode member, and wherein the second electrode has a width that is perpendicular, or substantially perpendicular, to the direction in which the electrode members are arranged, and the larger projections and larger pits are located at respective positions centered, or substantially centered, along the width.