Touch sensitive screen and method

• US 6,163,313 A
• Filed: 12/12/1997
• Issued: 12/19/2000
• Est. Priority Date: 12/12/1997
• Status: Expired due to Term

• Current Assignee: Elo Touch Solutions, Inc.
• Original Assignee: Elo Touchsystems Incorporated (Elo Touch Solutions, Inc.)
• Inventors: Aroyan, James L., Kent, Joel, Gomes, Paulo Irulegui
• Primary Examiner(s): Chow, Dennis-Doon
• Assistant Examiner(s): AWAD, AMR A
• Application Number:
  US08/989,928
• Time in Patent Office: 1,103 Days
• Field of Search: 345/173, 345/177, 178/18.05, 178/18.04, 178/18.06, 341/33, 707/535
• US Class Current: 345/173
• 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 position touch sensor having a substrate and a resistive layer disposed on the substrate. At least one pair of electrodes is positioned on the resistive layer. A portion of one electrode is spaced from a portion of another electrode to produce an overlapped resistive region between the spaced portions of the electrodes. An insulating region extends into and terminates in the overlapped resistive region from a resistive region of the resistive layer outside the overlapped resistive region. A method for controlling the flow of current through a resistive layer for converting physical position information on the resistive layer into electrical signals. The method includes determining a dimension of a length of a generally continuous resistive section which is to be located in the resistive layer. The dimension of the length is determined through the use of electrical excitation in the resistive layer. A first insulating region is disposed in the resistive layer to form a first boundary of the generally continuous resistive section. Subsequently and at a distance from the first insulating region essentially equaling the dimension of the length, a second insulating region is disposed in the resistive layer to form a second boundary of the generally continuous resistive section such that current may be conducted through the generally continuous resistive section between the first and second insulating regions.

Claims

1. A method for controlling the flow of current through a resistive layer for converting physical position information on the resistive layer into electrical signals comprising the steps of:

(a) providing a resistive layer for converting physical position information thereon into electrical signals;

(b) determining through the use of electrical excitation in the resistive layer a dimension of a length of a generally continuous resistive section which is to be located in the resistive layer of step (a);

(c) providing a pair of generally parallel electrodes engaged to said resistive layer to produce an overlapped resistive region in said resistive layer between said pair of generally parallel electrodes;

(d) disposing a first insulating region in the overlapped resistive region of step (c) to form a first boundary of the generally continuous resistive section;

(e) disposing, at a distance from the first insulating region essentially equaling the dimension of step (b), a second insulating region in the overlapped resistive region of step (c) to form a second boundary of the generally continuous resistive section such that current may be conducted through the generally continuous resistive section between the first insulating region and the second insulating region and such that said generally continuous resistive section is located in said overlapped resistive region.

2. The method of claim 1, additionally comprising extending said first insulating region in the generally continuous resistive layer of step (c) towards said second insulating region to decrease the dimension of the length of the generally continuous resistive section of step (b) and to increase the resistance of said generally continuous resistive section.

3. The method of claim 1 additionally comprising extending said first insulating region around an end of one of said pair of generally parallel electrodes.

4. The method of claim 1 additionally comprising providing a plurality of generally aligned and spaced electrodes engaged to said resistive layer with a respective end of any two contiguous electrodes being separated by a resistive region.

5. The method of claim 4 wherein said disposing step (c) includes disposing said first insulating region in said resistive region and said disposing step (d) includes disposing said second insulating region in said resistive region such that said generally continuous resistive section is located in said resistive region.

6. A position touch sensor, comprising:

a substrate;

a resistive layer on one face of the substrate;

a pair of electrodes, each of the electrodes positioned on and electrically connected to the resistive layer, the electrodes positioned on the substrate such that they are spaced apart and a portion of one of the electrodes extends along a portion of another one of electrodes providing a resistive region wherein the resistive region is bounded by the electrode portions at a first set of opposing sides of the resistive region and by boundaries delineated by an end of each portion of the electrodes at a second set of opposing sides;

a first insulating region extending from outside the resistive region to a terminating end within the resistive region wherein the first insulating region extends across a first side of the second set of opposing sides; and

a second insulating region extending from outside the resistive region to a terminating end within the resistive region across a second side of the second set of opposing sides, the second insulating region spaced apart from the first insulating region.

7. A position touch sensor as recited in claim 6, wherein the insulating region comprises a channel in the resistive layer.

8. A position touch sensor as recited in claim 7, wherein the channel is formed from the removal of a selected portion of the resistive layer.

9. A position touch sensor as recited in claim 7, wherein the channel extends from an outer surface of the resistive layer to the substrate.

10. A position touch sensor as recited in claim 6, wherein the insulating region comprises a first insulating portion extending from a side of the first electrode opposed to the second electrode to within the resistive region and a second insulating portion extending from a side of the second electrode opposed to the first electrode to within the resistive region, the first insulating portion and the second portion spaced apart within the resistive region.

11. A position touch sensor as recited in claim 10, wherein the first insulating portion comprises a segment that extends from the first electrode to the second electrode within the resistive region.

12. A position touch sensor as recited in claim 10, wherein the second insulating portion comprises a segment that extends from the first electrode to the second electrode within the resistive region.

13. A position touch sensor as recited in claim 10, wherein the first insulating portion and the second insulating portion each comprise a segment that extends from the first electrode to the second electrode within the resistive portion.

14. A position touch sensor as recited in claim 6, wherein the portion of the one electrode is generally parallel to the portion of the another one of the electrodes.

15. A position touch sensor, comprising:

a substrate;

a resistive layer on one face of the substrate;

a plurality of electrodes, each of the electrodes positioned on and electrically connected to the resistive layer, each pair of adjacent electrodes positioned such that they are spaced apart and a portion of one of the pair of electrodes extends along a portion of the other of the pair of electrodes providing a resistive region; and

an insulating region extending from outside the resistive region to a terminating end within the resistive region wherein the insulating region comprises a first insulating portion extending from a side of the first electrode opposed to the second electrode to within the resistive region and a second insulating portion extending from a side of the second electrode opposed to the first electrode to within the resistive region, the first insulating portion and the second portion spaced apart within the resistive region.

16. A position touch sensor as recited in claim 15, wherein the insulating region comprises a channel in the resistive layer.

17. A position touch sensor as recited in claim 16, wherein the channel is formed from the removal of a selected portion of the resistive layer.

18. A position touch sensor as recited in claim 16, wherein the channel extends from an outer surface of the resistive layer to the substrate.

19. A position touch sensor as recited in claim 15, wherein the resistive region is bounded by the electrode portions at a first set of opposing sides of the resistive region and by boundaries delineated by an end of each portion of the electrodes at a second set of opposing sides, the insulating region extending across a first side of the second set of opposing sides, the sensor further comprising a second insulating region extending from outside the resistive region to a terminating end within the resistive region across a second side of the second set of opposing sides, the second insulating region spaced apart from the first insulating region.

20. A position touch sensor as recited in claim 15, wherein the first insulating portion comprises a segment that extends from the first electrode to the second electrode within the resistive region.

21. A position touch sensor as recited in claim 15, wherein the second insulating portion comprises a segment that extends from the first electrode to the second electrode within the resistive region.

22. A position touch sensor as recited in claim 15, wherein the first insulating portion and the second insulating portion each comprise a segment that extends from the first electrode to the second electrode within the resistive portion.

23. A position touch sensor as recited in claim 15, wherein the portion of the one electrode is generally parallel to the portion of the another one of the electrodes.