Upon fabricating an opposite substrate, a concave portion having a predetermined depth is formed on the surface of a transparent substrate. Data packets to be transmitted upstream are stored at the cable modem. This can hold shading members 2 and 3 to a totally closed position after shutoff of electric current through a coil and can stably achieve an appropriate position of the stator yoke 10 in a rotation direction to eliminate the need for fixing the stator yoke 10 with an adhesive or the like. A stent may be disposed about at least a portion of the rotatable sheath and at least a portion of the secondary guide wire housing so that a distal end portion of the secondary guide wire housing exits the flow path of the stent through one of the plurality of cell openings which the stent defines.