| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a technique for sufficiently securing the valid time of an operation input reception means, thereby effectively performing a presentation using the operation input reception means. <P>SOLUTION: Not only the variation time (T1, T3, T5, T7, T9) of special symbols but also the stop-display time (T2, T4, T6, T8, T10) of the special symbols are set to time ranges of the valid time for validating the operation input of a presentation switch button. Thus, the operation input of the presentation switch can be received over the entire period from starting variation of the special symbols till stopping the variation of the special symbols, and from starting stop-display of the special symbols till ending the stop-display of the special symbols, and the valid time of the presentation switch button can be sufficiently secured. Thus, when performing the presentation using the presentation switch button over two or more times of variation of the special symbols, since the valid time of the presentation switch button is not interrupted, a longer valid period is secured. <P>COPYRIGHT: (C)2013,JPO&INPIT |
