Touch panel

• US 8,023,780 B2
• Filed: 11/03/2009
• Issued: 09/20/2011
• Est. Priority Date: 11/18/2008
• Status: Expired due to Fees

• Current Assignee: Nitto Denko Corporation
• Original Assignee: Nitto Denko Corporation
• Inventors: Juni, Noriyuki
• Primary Examiner(s): Petkovsek; Daniel
• Application Number:
  US12/611,602
• Publication Number:
  US 20100123682A1
• Time in Patent Office: 686 Days
• Field of Search: 345173-176, 385 12- 14, 385/32, 385/43, 385/46, 385129-132
• US Class Current: 385/14
• CPC Class Codes: G06F 3/0421 by interrupting or reflecting a light beam, e.g. optical touch-screen
• CPC Class Codes: G06F 3/046 by electromagnetic means

Abstract

A touch panel 30 of the present invention comprises: a light-emitting sided-optical waveguide 33; a light-receiving sided-optical waveguide 34; and an electromagnetic induction-type digitizer 36. In the touch panel of the present invention, a position coordinate is recognized using an electronic pen by an electromagnetic induction-type digitizer 36 when high resolution is required. A position coordinate is recognized using a finger by the optical waveguides 33 and 34 when high resolution is not required. This makes it possible to materialize the touch panel 30 having a high resolution and a lower power consumption regardless of its narrow frame.

Claims

1. A touch panel comprising:

a light-emitting element;

a coordinate input region;

a light-emitting sided-optical waveguide for guiding light emitted from the light-emitting element to generate light beams for crossing the coordinate input region and having an output end;

a light-receiving sided-optical waveguide for receiving the light beams having crossed the coordinate input region and having an input end;

a light-receiving element for detecting the intensity of light received at the light-receiving sided-optical waveguide; and

an electromagnetic induction-type digitizer provided in a lower part of the coordinate input region,

wherein the light-receiving sided-optical waveguide comprises;

cores; and

a cladding wherein the cores are embedded, the cores each including core branched groups arranged so as to receive light beams; and

core main paths for coupling the core branched groups to guide light to the light-receiving element.

2. The touch panel according to claim 1, wherein the number of the core branched groups coupled to the core main paths is 3 to 20.