OPTICAL WAVEGUIDE FOR TOUCH PANEL

• US 20080198144A1
• Filed: 02/19/2008
• Published: 08/21/2008
• Est. Priority Date: 02/19/2007
• Status: Active Grant

• Current Assignee: Nitto Denko Corporation
• Original Assignee: Nitto Denko Corporation
• Inventors: JUNI, Noriyuki, SHIMIZU, Yusuke
• Granted Patent: US 7,873,247 B2
• Time in Patent Office: Days
• US Class Current: 345/175
• CPC Class Codes: G06F 3/0421 by interrupting or reflecting a light beam, e.g. optical touch-screen

Abstract

An optical waveguide for a touch panel which includes a planar base; light emitting cores and light incident cores provided on a surface of the base; and an over-cladding layer covering the cores. The light emitting core has a first lens portion provided at the end thereof for suppressing lateral divergence of the emitted light beam, the over-cladding layer has a second lens portion provided in an edge portion thereof covering the end of the light emitting core for suppressing vertical divergence of the emitted light beam, the over-cladding layer has a third lens portion provided in an edge portion thereof covering the end of the light incident core for vertically converging the incident light beam, and the light incident core has a fourth lens portion provided at the end thereof for further laterally converging the incident light beam.

Claims

1. A touch panel optical waveguide to be disposed along a periphery of a display screen of a display of a touch panel, the touch panel optical waveguide comprising:

a planar base;

cores provided on a surface of the base; and

an over-cladding layer covering the cores;

the cores including a light emitting core having an end positioned on one side of the display screen of the display for emitting a light beam, and a light incident core having an end positioned on the other side of the display screen of the display for receiving a light beam incident thereon;

wherein the light emitting core has a first lens portion provided at the end thereof for suppressing lateral divergence of the emitted light beam;

wherein the over-cladding layer has a second lens portion provided in an edge portion thereof covering the end of the light emitting core for suppressing vertical divergence of the emitted light beam;

wherein the over-cladding layer has a third lens portion provided in an edge portion thereof covering the end of the light incident core for vertically converging the incident light beam;

wherein the light incident core has a fourth lens portion provided at the end thereof for further laterally converging the incident light beam.

2. The touch panel optical waveguide as set forth in claim 1, wherein the planar base is a base plate formed with a thin metal film or an under-cladding layer.

3. A band-shaped touch panel optical waveguide to be disposed along a periphery of a display of a touch panel, the touch panel optical waveguide comprising:

a light-transmissive under-cladding layer;

cores provided on a surface of the under-cladding layer; and

an over-cladding layer covering the cores;

the cores including a light emitting core having an end positioned on one side of the display for emitting a light beam, and a light incident core having an end positioned on the other side of the display for receiving a light beam incident thereon;

wherein the light emitting core has a first lens portion provided at the end thereof for suppressing lateral divergence of the emitted light beam;

wherein a first reflective layer which suppresses vertical divergence of the emitted light beam is provided on a surface of an edge portion of the over-cladding layer covering the end of the light emitting core;

wherein a second reflective layer which vertically converges the incident light beam is provided on a surface of an edge portion of the over-cladding layer covering the end of the light incident core;

wherein the light incident core has a fourth lens portion provided at the end thereof for further laterally converging the incident light beam.