Metal complexes having constrained geometry and a process for preparation thereof, addition polymerization catalysts formed therefrom, processes for preparation of such addition polymerization catalysts, methods of use, and novel polymers formed thereby, including ElPE resins and pseudo-random copolymers, are disclosed and claimed. Therefore, there is no plasma disturbance or metal contamination, and thus can be applied to a practical use. During a data transmission step, the coordinate indicator information data which has been detected is transmitted to the host computer by the tablet. The second interface is used to store and to retrieve data from the memory according to the second protocol. The light diffusive sheet of the present invention can prevent occurrence of a rainbow-like annular pattern without deteriorating the front luminance and view angle of the area light source even when combined with a downward-facing prism sheet.