POSITION DETECTING APPARATUS AND POSITION POINTER

• US 20090139780A1
• Filed: 01/05/2009
• Published: 06/04/2009
• Est. Priority Date: 11/14/2003
• Status: Active Grant

• Current Assignee: Sadao Yamamoto, Yuji Katsurahira
• Original Assignee: Sadao Yamamoto, Yuji Katsurahira
• Inventors: KATSURAHIRA, Yuji, Yamamoto, Sadao
• Granted Patent: US 8,253,702 B2
• Time in Patent Office: Days
• US Class Current: 178/18.30
• CPC Class Codes: G06F 1/3203 Power management, i.e. event-based initiation of a power-saving mode
• CPC Class Codes: G06F 1/3262 Power saving in digitizer or tablet
• CPC Class Codes: G06F 3/03545 Pens or stylus
• CPC Class Codes: G06F 3/046 by electromagnetic means

Abstract

In a position detecting apparatus, electric power of a position pointer is turned on only when the position pointer is put within a particular range from a tablet to minimize consumption of a battery disposed in the position pointer. When the position pointer is brought close to the tablet, a control signal transmitted from the tablet is detected by a resonant circuit of the position pointer, and MOSFETs serving as a power switch are turned on by the detected signal. In response, electric power is supplied from a battery via the MOSFETs to circuit elements of the position pointer, and thus an operation of the position pointer starts.

Claims

1. A position detecting apparatus comprising a tablet and a position pointer,

the tablet comprising:

control signal transmission means for transmitting a control signal to the position pointer to start an operation of the position pointer; and

detection means for detecting a position pointed to by the position pointer, based on a signal transmitted from the position pointer, and

the position pointer comprising;

a battery for supply electric power to circuit elements of the position pointer;

control signal detection means for detecting the control signal transmitted from the tablet; and

power control means for turning on or off the electric power supplied from the battery to the circuit elements in accordance with the control signal detected by the control signal detection means.

2-9. -9. (canceled)