0587200-A1 is referenced by 4 patents and cites 3 patents.

A method of detecting positions with a position detecting apparatus comprising: a position detecting section having a plurality of loop coils arrayed in a side-by-side-fashion in the direction of position detection for transmitting and receiving an electromagnetic wave with a predetermined frequency; and a position pointer (60) having a tuning circuit (61) including a coil (612) and a capacitor (613,615) and adapted to resonate with said electromagnetic wave; wherein the position of the position pointer (60) is determined from signals received by said loop coils from the tuning circuit (61) of the position pointer (60), when the latter is held in the vicinity of the position detecting section (10); ; and wherein, when said position pointer (60) is pressed onto the input surface of the position detecting section, a switch (611) associated with said tuning circuit (61) is turned on to change the phase of the oscillating current excited in the tuning circuit, and the phase of the electromagnetic wave received by said loop coils is detected, thereby to determine the status of said switch (611).

Title
Position detecting apparatus.
Application Number
EP19930118666 19931119
Publication Number
0587200 (A1)
Application Date
November 19, 1993
Publication Date
March 16, 1994
Inventor
Senda Toshiaki
JP
Funahashi Takahiko
JP
Yamanami Tsuguya
JP
Assignee
Wacom
JP
IPC
G06K 11/10
G06K 11/06
G06F 03/041
G06F 03/033
G06K 11/06
G06F 03/041
G06F 03/033
G06F 03/046
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