Patent ID: 8279528
Filing Date: 2012-10-02
Classification: G02B

Abstract:
1. An optical element comprising: a container including a first end face wall and a second end face wall facing each other, a side face wall connecting the first end face wall to the second end face wall, and a hermetically sealed accommodating chamber provided inside the end face walls and the side face wall; a first liquid having polarity or electrical conductivity and enclosed in the accommodating chamber; a second liquid immiscible with the first liquid and enclosed in the accommodating chamber; a first electrode and a second electrode configured to apply an electric field to the first liquid; an insulating film; and means for applying a voltage between the first electrode and the second electrode, wherein a transmittance of the first liquid is lower than a transmittance of the second liquid, a shape of an interface between the first liquid and the second liquid is changed by applying the voltage with the means for applying the voltage, and a light transmission path, a center of which is a single virtual axis passing through the first end face wall and the second end face wall and extending in a thickness direction of the container, which is a direction in which the first end face wall and the second end face wall face each other, is formed in a portion of the second liquid, the first electrode is provided on an inner surface of the first end face wall, the inner surface facing the accommodating chamber, the second electrode is provided on an inner surface of the second end face wall, the inner surface facing the accommodating chamber, the insulating film is provided on a surface of the second electrode, the surface facing the accommodating chamber, when viewed from the thickness direction of the container, an opening having a diameter a same as or smaller than a maximum diameter of the transmission path, the center of which is a virtual axis, is provided in the second electrode or in each of the second electrode and the insulating film, and wherein when an opening is provided in each of the second electrode and the insulating film and the opening of the second electrode has the same diameter as the maximum diameter of the transmission path, the opening of the insulating film has a diameter a same as or smaller than the diameter of the opening of the second electrode; wherein the opening is composed of a circular portion, the center of which is the virtual axis, and a plurality of projecting portions projecting from portions disposed on an outer circumference of the circular portion at intervals in a circumferential direction toward an outside in the radial direction.