| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a pen input device and a positional coordinate correcting method capable of preventing the generation of a deviation on positional coordinates due to the misreception of a top wave of an ultrasonic wave at a high response. SOLUTION: An ultrasonic wave transmitted from an ultrasonic wave sender of an input pen 1 is received by ultrasonic wave receiving elements 31a, 31b, a distance between the sender and the receiving elements 31a, 31b is calculated by a reception processing part 32 based on time required from the sending of the ultrasonic wave up to its reception and the distance is sent to an arithmetic processing part 40 through a communication part 33. The processing part 40 calculates the positional coordinates of the input pen 1 by the use of the inputted distance data and displays the calculated result on a display part 50. At the time the processing part 40 compares past measurement data with current measurement data, and when its difference coincides with one wavelength of the ultrasonic wave, the current measurement data are substituted for the past measurement data and reculcuiates the positional coordinates of the input pen 1.</p> |
