Capacitance type sensor
A capacitance type sensor includes: a dielectric layer made of a polymer; an elongated front-side electrode placed on a front side of the dielectric layer; an elongated back-side electrode placed on a back side of the dielectric layer; a front-side wiring connected to the front-side electrode; a back-side wiring connected to the back-side electrode; and a plurality of detection portions formed between the front-side electrode and the back-side electrode. Each of the front-side electrode and the back-side electrode has an elongated electrode body containing a binder and a conductive material, and an extended wiring portion extending in a longitudinal direction of the electrode body and having lower volume resistivity than the electrode body, and the front-side wiring and the back-side wiring have lower volume resistivity than the electrode body.
1. A capacitance type sensor, comprising:
a dielectric layer made of a polymer;
an elongated front-side electrode placed on a front side of the dielectric layer;
an elongated back-side electrode placed on a back side of the dielectric layer;
a front-side wiring connected to the front-side electrode;
a back-side wiring connected to the back-side electrode; and
a plurality of detection portions formed between the front-side electrode and the back-side electrode which face each other in a front-back direction,
the capacitance type sensor being capable of detecting surface pressure distribution based on a change in capacitance of a detection portion, characterized in that
each of the front-side electrode and the back-side electrode has an elongated electrode body containing a binder and a conductive material, and an extended wiring portion extending in a longitudinal direction of the electrode body and having lower volume resistivity than the electrode body, and
the front-side wiring and the back-side wiring have lower volume resistivity than the electrode body.
2. The capacitance type sensor according to claim 1 , wherein
the extended wiring portion of the front-side electrode and the front-side wiring are made of the same material such that the extended wiring portion of the front-side electrode is continuous with the front-side wiring, and
the extended wiring portion of the back-side electrode and the back-side wiring are made of the same material such that the extended wiring portion of the back-side electrode is continuous with the back-side wiring.
3. The capacitance type sensor according to claim 1 , wherein
the binder of the electrode body is a resin.
4. The capacitance type sensor according to claim 1 , wherein
the volume resistivity of the electrode body is 1×10 1 Ω·cm or less.
5. The capacitance type sensor according to claim 1 , wherein
the extended wiring portion contains a binder and a metal powder.
6. The capacitance type sensor according to claim 1 , wherein
in each of the front-side electrode and the back-side electrode, electrical resistance between an upstream end to which the front-side wiring or the back-side wiring is connected and a downstream end as a longitudinal terminal end is 3,000Ω or less.
7. The capacitance type sensor according to claim 1 , wherein
the extended wiring portion has a smaller area than the electrode body.
8. The capacitance type sensor according to claim 1 , wherein
the electrode body and the extended wiring portion are printed.
9. The capacitance type sensor according to claim 1 , further comprising:
a pair of front-side and back-side sheets that are placed with the dielectric layer interposed therebetween,
the front-side electrode is formed on a back surface of the front-side sheet which contacts the dielectric layer, and the extended wiring portion of the front-side electrode is interposed between the electrode body and the front-side sheet, and
the back-side electrode is formed on a front surface of the back-side sheet which contacts the dielectric layer, and the extended wiring portion of the back-side electrode is interposed between the electrode body and the back-side sheet.