Generally, in the out of beam scanning area in the target of a camera tube, the surface potential of the target increases to almost the same voltage applied to the target. In the case of the Super-HARP tube, this phenomenon influences the beam landing characteristics and sometimes causes spurious images on the edge of the picture because of the very high voltage applied to the target. In order to decrease the surface potential, a new target structure has been developed, which has very little sensitivity. It is confirmed that the spurious images can be eliminated by applying this structure to the outside of the beam scanning area.
