Method for manufacturing touch screen linearization pattern

• US 6,673,390 B2
• Filed: 03/23/2001
• Issued: 01/06/2004
• Est. Priority Date: 03/23/2001
• Status: Active Grant

• Current Assignee: Eturbotouch Technology Inc., Wistron Corporation
• Original Assignee: Eturbotouch Technology Inc.
• Inventors: Chen, Chi-Ruey
• Primary Examiner(s): Talbot, Brian K.
• Application Number:
  US09/814,843
• Publication Number:
  US 20020135569A1
• Time in Patent Office: 1,019 Days
• Field of Search: 178/18.01, 178/19.01, 178/20.01, 427/58, 427/282, 427/201, 427/125, 427/101, 427/284, 427/287, 427/269, 427/126.2, 345/156, 345/173
• US Class Current: 427/101
• CPC Class Codes: G06F 2203/04113 Peripheral electrode pattern in resistive digitisers, i.e. electrodes at the periphery of the resistive sheet are shaped in patterns enhancing linearity of induced field
• CPC Class Codes: G06F 3/045 using resistive elements, e.g. a single continuous surface or two parallel surfaces put in contact

Abstract

A method for manufacturing a touch screen linearization pattern which is necessary for a five wire resistive type or current sensing type touch screen, and directly affects the accuracy, production price, and border area size of the touch screen, includes the steps of printing a linearization pattern on the border area of a conductive glass surface with a selected ink. The ink is made by blending highly conductive silver powder between about 59% to 62% in weight and carbon powder between about 14% to 16% in a contact agent solvent between about 24% to 25% in weight. The touch screen thus formed has a resistance value ratio of about ten between the square surface of the glass layer and the two ends of the linearization pattern.

Claims

1. A method for manufacturing a linearization pattern for a touch screen including a glass layer having a surface on which a conductive layer having a low conductivity has been sputter coated, a linearization pattern, an isolation layer, a four wire silver printing layer and a tail cable connected to a controller, the controller being arranged to output four equal voltages to four ends of the touch screen and to measure current variation, comprising the steps of:

making an ink by blending highly conductive material of silver powder in a percentage weight range of between about 59% to 62% and carbon powder in a percentage weight range of between about 14% to 16% in a contact agent solvent having a percentage weight range of between about 24% to 25%; and

using the ink to print a linearization pattern on a border of the sputter-coated glass layer surface to form a linearization pattern such that a resistance value ratio between a square of the sputter-coated glass layer and two ends of the linearization pattern is about 10.

2. The method of claim 1, wherein the sputter-coated glass layer is made of Indium Tin Oxide glass which has a resistance of value of 500Ω

per square or 1500Ω

per square.

3. The method of claim 1, wherein the resistance coefficient of the linearization pattern is determined by the material of the pattern and is changeable through variation of the contained acceptable silver powder and carbon powder, and is changeable by the size and shape of the linearization pattern in order to achieve said resistance value ratio of about 10.

4. The method of claim 1, wherein the linearization pattern has a height of 10 micro meter which has a resistance of 0.5 ohm per square, and has a width of 3 mm and a length of 300 mm for a total resistance of 100Ω

at two sides thereof and 50Ω

at each side, and wherein the sputter-coated glass layer is Indium Tin Oxide glass which hits a 500Ω

per square resistance thereby providing a resistance ratio of 10;

1 between the Indium Tin Oxide resistance value and the resistance value of the linearization patterns.

6. A method for manufacturing a linearization pattern for a touch screen including a glass layer having a surface on which a lower ITO conductive layer has been sputter coated, a linearization pattern, a set of insulation points, an isolation layer, a four wire silver printing layer, another isolation layer, an upper ITO conductive layer, a plastic layer and a tail cable connected to a controller, the upper ITO layer being contactable to the lower ITO layer for measuring the voltage of the contact point, comprising the steps of:

making an ink by blending highly conductive material of silver powder in a percentage weight range of between about 59% to 62%, and carbon powder in a percentage weight range of between about 14% to 16% in a contact agent solvent having a percentage weight range of between about 24% to 25%; and

using the ink to print a linearization pattern on a border of the sputter-coated glass layer surface to form a linearization pattern such that a resistance value ratio between a square of the sputter-coated glass layer and two ends of the linearization pattern is about 10.

5. The method of claim 6, wherein the linearization pattern has a height of 10 micro meter which has a resistance of 1 ohm per squares and has a width of 3 mm and a length of 300 mm for a resistance of 100Ω

at each side, and wherein the sputter-coated glass layer is Indium Tin Oxide glass which has a 1000Ω

per square resistance, thereby providing a resistance ratio of 10;

1 between the Indium Tin Oxide resistance value and the resistance value of the linearization patterns.

7. The method of claim 6, wherein the sputter-coated glass layer is made of Indium Tin Oxide glass which has a resistance of value of 500Ω

per square or 1500Ω

per square.

8. The method of claim 6, wherein the resistance coefficient of the linearization pattern is determined by the material of the pattern and is changeable through variation of the contained acceptable silver powder and carbon powder, and is changeable by the size and shape of the linearization pattern in order to achieve said resistance value ratio of about 10.

9. The method of claim 6, wherein the linearization pattern has a height of 10 micro meter which has a resistance of 0.5 ohm per square, and has a width of 3 mm and a length of 300 mm for a total resistance of 100Ω

at two sides thereof and 50Ω

at each side, and wherein the sputter-coated glass layer is Indium tin Oxide glass which has a 500Ω

per square resistance, thereby providing a resistance ratio of 10;

1 between the Indium Tin Oxide resistance value and the resistance value of the linearization patterns.

10. The method of claim 6, wherein the linearization pattern has a height of 10 micro meter which has a resistance of 1 ohm per square, and has a width of 3 mm and a length of 300 mm for a resistance of 100Ω

at each side, and wherein the sputter-coated glass layer is Indium tin Oxide glass which has a 1000Ω

per square resistance, thereby providing a resistance ratio of 10;

1 between the Indium Tin Oxide resistance value and the resistance value of the linearization patterns.