Conductive film, and display device having the same

Patent metadata

Field	Value
Publication number	US-10649605-B2
Application number	US-201916424597-A
Country	US
Kind code	B2
Filing date	May 29, 2019
Priority date	Mar 31, 2015
Publication date	May 12, 2020
Grant date	May 12, 2020

Abstract

A conductive film includes a wiring pattern having the following characteristics. For each spectrum in which spectrum peaks obtained by performing two-dimensional Fourier transform on transmittance image data of the entire image has normalized spectrum intensities equal to or greater than a specified value, an angle is set to oscillate by each unit of a specific angle. Intensity differences, each of which is obtained from a maximum value and a minimum value of the normalized spectrum intensity for each angle, are calculated. One or more clusters of bars, which indicate frequencies of a histogram at an average value or more of the intensity difference in a case where the histogram is a histogram of the intensity differences, are isolated from the other cluster. In addition, in a case where a second sample standard deviation indicating a variation of first sample standard deviations, each of which indicates a variation of the normalized spectrum intensities at a single angle, in all angular directions is calculated as a quantitative value of the wiring pattern, the quantitative value is in a specific numerical value range.

First claim

What is claimed is:

1. A conductive film that is provided on a display unit of a display device, the conductive film comprising:
a transparent substrate; and
a conductive section that is formed on at least one surface of the transparent substrate and is formed of a plurality of thin metal lines,
wherein the conductive section has a wiring pattern which is formed in a mesh shape by the plurality of thin metal lines and in which a plurality of opening portions is arranged,
wherein the mesh shape of the wiring pattern is characterized by a quantitative value from normalized spectrum intensities of spectrum peaks of an entire image of the wiring pattern obtained by performing two-dimensional Fourier transform on transmittance image data of the entire image of the mesh pattern, wherein spectra, which have the normalized spectrum intensities equal to or greater than a specified value are extracted as extracted spectrum, and angles formed between a) one coordinate axis of two-dimensional Fourier coordinates and b) a straight line connecting coordinates of each extracted spectrum and an origin of the two-dimensional Fourier coordinates, are calculated in units of a specific angle for the each extracted spectrum, and wherein intensity differences obtained from a maximum value and a minimum value of the normalized spectrum intensity for each angle are calculated at all points of the extracted spectrum by oscillating the angle by each unit of the specific angle, and further with respect to the extracted spectrum, and with further regard to the intensity differences, determining a histogram of intensity differences at all the points and isolating one or more clusters of bars, which indicate frequencies of a histogram at an average value, and of the isolated bars, a second sample standard deviation indicating a variation of first sample standard deviations, each of which indicates a variation of the normalized spectrum intensities at a single angle, in all angular directions sets the quantitative value of the wiring pattern, and wherein the quantitative value is in a specific numerical value range to characterized the shape of the mesh pattern,
wherein each normalized spectrum intensity is a standard value which is normalized by an image size and an average value of a spectrum intensity of each spectrum of the entire image, wherein the specified value is −4.0 as a value which is 10,000 times a logarithmic value of a value of the normalized spectrum intensity, wherein the unit of the specific angle is 1 degree, wherein each intensity difference is 10.000 times a logarithmic value of a value of a difference between a maximum value and a minimum value of the normalized spectrum intensity at one angle, wherein a range of the intensity difference forming a horizontal axis of the histogram is from −4.0 to 0, and a step width of the range is 0.1, and wherein the specific numerical value range is from −5.29 to −5.05.

2. The conductive film according to claim 1 , wherein the angle is obtained by calculating a value of the angle up to two decimal places and rounding off the value with two decimal places to one decimal place.

3. The conductive film according to claim 1 , wherein the wiring pattern is formed by generating a plurality of dots regularly arranged on a rectangular plane, moving the arranged dots in arbitrary directions of 360 degrees using random numbers so as to give randomicity, generating polygons centering on the randomly arranged dots, and thinning a region between the polygons.

4. The conductive film according to claim 1 , wherein the wiring pattern is superposed on a pixel array pattern of the display unit.

5. The conductive film according to claim 4 , wherein the pixel array pattern is a black matrix pattern.

6. A display device comprising:
a display unit; and
the conductive film according to claim 1 , the conductive film being provided on the display unit.

Assignees

• Fujifilm Corp

Inventors

• Iwami Kazuchika

Classifications

• G06F3/047

  using sets of wires, e.g. crossed wires · CPC title

• G06F3/041

  Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means · CPC title

• G06F2203/04112

  Electrode mesh in capacitive digitiser: electrode for touch sensing is formed of a mesh of very fine, normally metallic, interconnected lines that are almost invisible to see. This provides a quite large but transparent electrode surface, without need for ITO or similar transparent conductive material · CPC title

• B32B7/12

  using interposed adhesives or interposed materials with bonding properties · CPC title

• G06F3/0412

  Digitisers structurally integrated in a display · CPC title