Patent ID: 6850356

Claim:
An optical element comprising at least: two substrates that are disposed opposite to each other; a liquid disposed between facing surfaces of the opposed substrates; and at least one chargeable polymer particle disposed between the facing surfaces of the substrates for swelling or contracting by absorbing or releasing the liquid when an electric field is applied, wherein at least one of the facing surfaces includes at least an adhering fixing portion that fixes the chargeable polymer particle thereon and the chargeable polymer particle is fixed to the at least one facing surface via the adhering fixing portion, wherein (1) an area of each adhering fixing portion is smaller than a maximum sectional area of the chargeable polymer particle at the time of maximum swelling, and (2) a non-adhesive portion surrounds each adhering fixing portion, and the non-adhesive portion is disposed at least at a largest outer circumference of the chargeable polymer particle at the time of maximum swelling and extends inside the largest outer circumference of the chargeable polymer at the time of maximum swelling.