Touch panel sensor

• US 8,742,772 B2
• Filed: 10/17/2012
• Issued: 06/03/2014
• Est. Priority Date: 11/25/2011
• Status: Active Grant

• Current Assignee: Nitto Denko Corporation
• Original Assignee: Nitto Denko Corporation
• Inventors: Takao, Hiroyuki, Tsuno, Naoki, Takada, Katsunori
• Primary Examiner(s): Nguyen, Tung X
• Assistant Examiner(s): LE, THANG XUAN
• Application Number:
  US13/653,575
• Publication Number:
  US 20130134993A1
• Time in Patent Office: 594 Days
• Field of Search: 324658-661, 324/686, 345/173, 345/174, 349/113, 349/118, 349/176, 349/132, 313581-587
• US Class Current: 324/661
• CPC Class Codes: G06F 3/0445 using two or more layers of sensing electrodes, e.g. using two layers of electrodes separated by a dielectric layer
• CPC Class Codes: G06F 3/0446 using a grid-like structure of electrodes in at least two directions, e.g. using row and column electrodes

Abstract

A touch panel sensor with which unevenness of interference can be reduced is provided. A touch panel sensor of the present invention includes a film base material, a first transparent electrode pattern formed on a first face of the film base material, a first adhesive layer laminated on the first face of the film base material so as to cover the first transparent electrode pattern, a second transparent electrode pattern formed on a second face of the film base material, and a second adhesive layer laminated on the second face of the film base material so as to cover the second transparent electrode pattern, and the film base material has an in-plane phase difference of λ/4 with respect to a wavelength λ in the visible light region.

Claims

1. A touch panel sensor comprising:

a film base material;

a first transparent electrode pattern formed on a first face of the film base material;

a first adhesive layer laminated on the first face of the film base material so as to cover the first transparent electrode pattern;

a second transparent electrode pattern formed on a second face of the film base material; and

a second adhesive layer laminated on the second face of the film base material so as to cover the second transparent electrode pattern,

wherein the film base material has an in-plane phase difference of λ

/4 with respect to a wavelength λ

in a visible light region, and

n_e1−

n_a1≧

0.3 and n_e2−

n_a2≧

0.3, where n_e1 is a refractive index of the first transparent electrode pattern, n_e2 is a refractive index of the second transparent electrode pattern, n_a1 is a refractive index of the first adhesive layer, and n_a2 is a refractive index of the second adhesive layer.

2. The touch panel sensor according to claim 1, wherein the refractive index n_e1 of the first transparent electrode pattern and the refractive index n_e2 of the second transparent electrode pattern are each 1.9 to 2.5.

3. The touch panel sensor according to claim 1, wherein each of the first transparent electrode pattern and the second transparent electrode pattern is formed of indium tin oxide, indium zinc oxide, or a composite oxide of indium oxide and zinc oxide.

4. The touch panel sensor according to claim 1, wherein the refractive index n_a1 of the first adhesive layer and the refractive index n_a2 of the second adhesive layer are each 1.4 to 1.6.

5. The touch panel sensor according to claim 1, wherein the first adhesive layer and the second adhesive layer are pressure-sensitive adhesives formed of an acrylic adhesive.

6. The touch panel sensor according to claim 1, wherein the film base material is formed by drawing a film formed of a material selected from polyethylene terephthalate, polycycloolefin, or polycarbonate in one direction.

7. The touch panel sensor according to claim 1, wherein the film base material is formed by drawing a polycycloolefin film in one direction.