Coordinate detection apparatus

• US 9,778,809 B2
• Filed: 12/07/2015
• Issued: 10/03/2017
• Est. Priority Date: 04/23/2008
• Status: Active Grant

• Current Assignee: Fujitsu Component Limited (Fujitsu Limited)
• Original Assignee: Fujitsu Component Limited (Fujitsu Limited)
• Inventors: Kondoh, Koichi, Furukawa, Shozo, Sekizawa, Mitsuhiro, Nakajima, Takashi
• Primary Examiner(s): REGN, MARK W
• Application Number:
  US14/960,600
• Publication Number:
  US 20160085344A1
• Time in Patent Office: 666 Days
• Field of Search: 345174
• CPC Class Codes: G06F 2203/04103 Manufacturing, i.e. details related to manufacturing processes specially suited for touch sensitive devices
• CPC Class Codes: G06F 3/045 using resistive elements, e.g. a single continuous surface or two parallel surfaces put in contact
• CPC Class Codes: G06F 3/047 using sets of wires, e.g. crossed wires

Abstract

In a coordinate detection apparatus, a resistance-film is formed on a substrate made of an insulating material. A common electrode applies a voltage to the resistance-film, the common electrode extending along a plurality of a resistance-film removal areas formed by removing portions of the resistance-film. A voltage application part applies the voltage to the common electrode. The voltage is applied from the voltage application part to the resistance-film through the common electrode to generate a potential distribution in the resistance-film. A coordinate position of a contact position at which the resistance-film is contacted is detected by detecting a potential of the resistance-film at the contact position.

Claims

1. A coordinate detection apparatus comprising:

a resistance-film formed on a substrate;

a plurality of resistance-film removal areas provided along outer sides of the substrate, each of the plurality of resistance-film removal areas is formed by removing a portion of the resistance-film;

a plurality of potential supply parts of the resistance film provided between two resistance-film removal areas from among the plurality of resistance-film removal areas; and

a plurality of common electrodes respectively arranged along the outer sides of the substrate, each of the plurality of common electrodes being formed over the plurality of resistance-film removal areas, the plurality of common electrodes being configured to contact the plurality of potential supply parts so as to apply a voltage to the resistance-film through the plurality of potential supply parts,

wherein the resistance-film removal areas are configured and arranged so that a uniform potential distribution is generated in the resistance-film when the voltage is applied to the resistance film, and

wherein each of the plurality of potential supply parts is formed so that a contact area between the common electrode and the resistance-film per unit length is gradually reduced from a middle portion of each of the outer sides of the substrate toward each end of the outer sides.

2. The coordinate detection apparatus as claimed in claim 1, further comprising:

a plurality of second resistance-film removal areas formed along the plurality of common electrodes within an area surrounded by the plurality of common electrodes.

3. The coordinate detection apparatus as claimed in claim 1,

wherein at least one of pitches of the resistance-film removal areas and intervals between adjacent resistance-film removal areas are equal to each other, respectively.

4. The coordinate detection apparatus as claimed in claim 1,

wherein each of the resistance-film removal areas has the same shape.

5. A coordinate detection apparatus comprising:

a resistance-film formed on a substrate;

a plurality of resistance-film removal areas provided along outer sides of the substrate, each of the plurality of resistance-film removal areas is formed by removing a portion of the resistance-film;

a plurality of potential supply parts of the resistance film provided between two resistance-film removal areas from among the plurality of resistance-film removal areas; and

a plurality of common electrodes respectively arranged along the outer sides of the substrate, each of the plurality of common electrodes being respectively formed over the plurality of resistance-film removal areas, the plurality of common electrodes being configured to contact the plurality of potential supply parts so as to apply a voltage to the resistance-film through the plurality of potential supply parts,

wherein the resistance-film removal areas are configured and arranged so that a uniform potential distribution is generated in the resistance-film when the voltage is applied to the resistance film, and

wherein each of the plurality of potential supply parts is formed so that a number of the plurality of potential supply parts per unit length is gradually reduced from a middle portion of each of the outer sides of the substrate toward each end of the outer sides.