PURPOSE: To detect the exact position of coordinates by correcting an oscillation transmitting time to an attention oscillation sensor based on the change of a signal characteristic to be detected by the oscillation sensor and calculating the coordinate position of an oscillating pen based on the correspondent oscillation transmitting time.
CONSTITUTION: A user has an oscillating pen 3 in a hand and inputs the coordinates in the position on an oscillation transmitting board 8. The oscillation transmitting board 8 transmits the ultrasonic oscillation, which is received from the oscillating pen 3, to oscillation sensors 6a-6c. Signals to be detected by the sensors 6a-6c are respectively given to a signal waveform detecting circuit 9 and from the oscillation transmitting time to the sensor to be obtained by the detecting circuit 9, the position of the oscillating pen 3 is detected in an arithmetic and control circuit 1. The detecting circuit 9 detects the change of the signal characteristic in the detected signal, for example, an envelope level and the detected change is sent to the circuit 1. The circuit 1 corrects the oscillation transmitting time to the attention sensor based on the detected result of the envelope level and detects the position of the oscillating pen 3. Then, the correct position of the coordinates can be detected.
YOSHIMURA YUICHIRO
TANIISHI SHINNOSUKE
KOBAYASHI KATSUYUKI
KAMONO TAKESHI
YANAGISAWA RYOZO
| JPS61240316A | 1986-10-25 | |||
| JPS61183733A | 1986-08-16 | |||
| JPS61183732A | 1986-08-16 | |||
| JPS61194523A | 1986-08-28 |