| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To reduce power consumption in a pen and a fixed machine according to the state of the pen regarding an ultrasonic type coordinate input device. <P>SOLUTION: The ultrasonic type coordinate input device is constituted such that the state of pen 1 is decided by using a microcomputer inside the pen 1, transmission is performed by changing the interval of a plurality of infrared ray pulses according to the state of the pen 1 and ultrasonic signals are transmitted to the fixed machine 2 simultaneously only in the case that there is a state change, and an infrared ray synchronizing signal composed of one pulse is transmitted to the fixed machine 2 in the case that there is no state change. The fixed machine 2 detects the state of the pen 1 on the basis of the infrared ray signals transmitted from the pen 1, and interrupts the power of the ultrasonic reception part of the fixed machine 2 in the case of the state that the pen 1 is raised and a button is not depressed. <P>COPYRIGHT: (C)2005,JPO&NCIPI</p> |
