In an image display apparatus, image data on which gradation conversion for compensating phosphor saturation has been carried out by a gradation convertor undergoes voltage drop compensation and then amplitude regulation using a gain before being fed to modulating means. The computer system comprises at least two cabinets and the at least two cabinets have at least one clock signal. Then, an accumulator collects the wage assignment information from at least one initiator, such as a government agency. Thus, the appearance of the pointer type indicating apparatus can be simplified, and the user can be provided with an intuitionistic operation.