| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To improve the reliability of coordinates by deciding a reflected wave and an impulsive sound noise in a coordinate input device for calculating the coordinates of an oscillation source by detecting ultrasonic waves propagating in air. <P>SOLUTION: The correlation coefficient between the detected waveform and the reference waveform from an oscillation source is calculated, and the decision of the correctness of the detected waveform is executed from the pattern of a displacement data column. Also, a reference range for calculating the correlation coefficients is changed according to the input position, so that a sampling speed is improved in the case of on-screen input, and that reliability is also improved in the case of input away from a screen. <P>COPYRIGHT: (C)2004,JPO&NCIPI</p> |
