Optical waveguide, optical waveguide type touch panel and method of manufacturing the optical waveguide

• US 8,325,158 B2
• Filed: 07/14/2009
• Issued: 12/04/2012
• Est. Priority Date: 12/24/2008
• Status: Expired due to Fees

• Current Assignee: Fuji Xerox Company Limited (Xerox Holdings Corp.)
• Original Assignee: Fuji Xerox Company Limited (Xerox Holdings Corp.)
• Inventors: Yatsuda, Kazutoshi, Igusa, Masahiro, Fujii, Akira, Suzuki, Toshihiko, Shimizu, Keishi, Ohtsu, Shigemi
• Primary Examiner(s): Sniezek, Andrew L
• Application Number:
  US12/502,583
• Publication Number:
  US 20100156848A1
• Time in Patent Office: 1,239 Days
• Field of Search: None
• US Class Current: 345/176
• CPC Class Codes: B29D 11/00663 Production of light guides
• CPC Class Codes: G02B 6/2852 using tapping light guides arranged sidewardly, e.g. in a non-parallel relationship with respect to the bus light guides (light extraction or launching through cladding, with or without surface discontinuities, bent structures)
• CPC Class Codes: G02B 6/4214 the intermediate optical element having redirecting reflective means, e.g. mirrors, prisms for deflecting the radiation from horizontal to down- or upward direction toward a device G02B6/4246 takes precedence
• CPC Class Codes: G06F 2203/04109 FTIR in optical digitiser, i.e. touch detection by frustrating the total internal reflection within an optical waveguide due to changes of optical properties or deformation at the touch location
• CPC Class Codes: G06F 3/0421 by interrupting or reflecting a light beam, e.g. optical touch-screen

Abstract

A method of manufacturing an optical waveguide includes forming a core layer on a first clad layer, forming a second clad layer on the core layer, forming a first groove including at least one inclined surface in the second clad layer and the core layer to be in substantially parallel to and near one end of the second clad layer and one end of the core layer, the at least one inclined surface of the first groove having such an angle that the core layer is exposed when viewed above the second clad layer, forming a second groove including at least one inclined surface in the second clad layer on a inner side of the first groove, forming a separation groove in the clad layers and the core layer in a direction intersecting the first groove, and forming a plurality of cores intersecting the first groove.

Claims

1. An optical waveguide comprising:

a clad that has a first surface and second surface which is opposed to the first surface, the clad being plate-like;

a plurality of first cores that is provided in a first layer in the clad;

a plurality of first reflecting surfaces each of which is provided in one end of a corresponding one of the first cores, each first reflecting surface that reflects light being incident from the second surface, so as to propagate the light through the first core; and

a plurality of third reflecting surfaces each of which reflects light going out of a corresponding one of the first cores and propagating through the clad among the light reflected by the first reflecting surface, toward a direction different from an axial direction of the corresponding one of the first cores.

2. The optical waveguide according to claim 1, further comprising

a plurality of second cores that is provided in a second layer in the clad, the second layer being different from the first layer, the second cores that intersect the first cores when viewed from the first surface;

a plurality of second reflecting surfaces each of which is provided in one end of a corresponding one of the second cores, each second reflecting surface that reflects light being incident from the second surface, so as to propagate the light through the second core; and

a plurality of fourth reflecting surfaces each of which reflects light going out of a corresponding one of the second cores and propagating through the clad among the light reflected by the second reflecting surface, toward a direction different from an axial direction of the corresponding one of the second cores.

3. The optical waveguide according to claim 1, wherein

the optical waveguide has 40 or less in an Hs hardness, and

the optical waveguide has a numerical aperture in a range of 0.01 to 0.2.

4. The optical waveguide according to claim 2, wherein

the optical waveguide has 40 or less in an Hs hardness, and

the optical waveguide has a numerical aperture in a range of 0.01 to 0.2.

5. An optical waveguide type touch panel comprising:

an optical waveguide including a clad that has a first surface and a second surface which is opposed to the first surface, a plurality of first cores that is provided in a first layer in the clad, and a plurality of second cores that is provided in a second layer in the clad, the second layer being different from the first layer, the second cores that intersect the first cores when viewed from the first surface;

a liquid crystal panel that is disposed at the second surface;

a light source that irradiates the optical waveguide with light through the liquid crystal panel;

a plurality of first light receiving elements each of which is disposed at one end of a corresponding one of the first cores of the optical waveguide;

a plurality of second light receiving elements each of which is disposed at one end of a corresponding one of the second cores of the optical waveguide;

a plurality of first reflecting surfaces that is provided in the other ends of the plurality of first cores, respectively, each first reflecting surface that reflects the light from the light source so as to propagate the light through the corresponding one of the first cores and cause the light to be incident into the corresponding one of the first light receiving elements;

a plurality of second reflecting surfaces that is provided in the other ends of the plurality of second cores, respectively, each second reflecting surface that reflects the light from the light source so as to propagate the light through the corresponding one of the second cores and cause the light to be incident into the corresponding one of the second light receiving elements;

a plurality of third reflecting surfaces each of which reflects light going out of a corresponding one of the first cores and propagating through the clad among the light reflected by the each first reflecting surface, toward a direction different from an axial direction of the corresponding one of the first cores;

a plurality of fourth reflecting surfaces each of which reflects light going out of a corresponding one of the second cores and propagating through the clad among the light reflected by a corresponding one of the second reflecting surfaces, toward a direction different from an axial direction of the corresponding one of the second cores; and

a detector that detects a position where the first and second cores are deformed by partially pressing the first surface, based on signals from the plurality of first and second light receiving elements.

6. The optical waveguide type touch panel according to claim 5, wherein

the optical waveguide has 40 or less in Hs hardness, and

the optical waveguide has a numerical aperture in a range of 0.01 to 0.2.