An apparatus for configuring a spanning tree is used for a network in which a plurality of virtual LANs coexist. Moreover, a system controller judges whether pixel shift photography has been normally performed or not based on the pixel shift evaluation value, and displays the judgment result on a display. The antenna extends across a joint between the first and second antenna carriers. To improve the emission, a plurality of optically active surface portions are provided arranged around the point at which the longitudinal axis of the recess passes through the cover wall and each of which has a focal point lying on the longitudinal axis and the focal points of at least two of the surface portions are at a mutual spacing in the direction of the longitudinal axis.