HYBRID SENSOR

• US 20140210490A1
• Filed: 03/27/2014
• Published: 07/31/2014
• Est. Priority Date: 03/02/2012
• Status: Active Grant

• Current Assignee: Sumitomo Riko Company Limited.
• Original Assignee: Tokai Rubber Industries Limited
• Inventors: HAYAKAWA, Tomonori, UKAI, Hitoshi
• Granted Patent: US 9,494,544 B2
• Time in Patent Office: Days
• US Class Current: 324/658
• CPC Class Codes: G01L 1/14 by measuring variations in capacitance or inductance of electrical elements, e.g. by measuring variations of frequency of electrical oscillators
• CPC Class Codes: G01N 27/22 by investigating capacitance
• CPC Class Codes: G06F 2203/04106 Multi-sensing digitiser, i.e. digitiser using at least two different sensing technologies simultaneously or alternatively, e.g. for detecting pen and finger, for saving power or for improving position detection
• CPC Class Codes: G06F 3/04166 Details of scanning methods, e.g. sampling time, grouping of sub areas or time sharing with display driving Synchronisation with the driving of the display or the backlighting unit to avoid interferences generated internally G06F3/04184
• CPC Class Codes: G06F 3/0445 using two or more layers of sensing electrodes, e.g. using two layers of electrodes separated by a dielectric layer
• CPC Class Codes: G06F 3/0446 using a grid-like structure of electrodes in at least two directions, e.g. using row and column electrodes
• CPC Class Codes: G06F 3/0447 Position sensing using the local deformation of sensor cells

Abstract

A hybrid sensor includes a proximity sensor section and a load sensor section. The proximity sensor section includes a first base material, a plurality of first front-side electrodes, a plurality of first back-side electrodes, and a protective layer. Each of these members is made of an elastomer. The proximity sensor section detects the approach and coordinates of an object to be detected, based on a change in capacitance between the first front-side electrode and the first back-side electrode which is caused by the approach of the object to be detected. The load sensor section detects pressing and coordinates of the object to be detected, based on a load that is applied from the object to be detected via the proximity sensor section.

Claims

1. A hybrid sensor, comprising:

a proximity sensor section that includes a first base material having insulating properties and made of an elastomer, a plurality of first front-side electrodes disposed on a front side of the first base material, having conductive properties, and made of an elastomer, a plurality of first back-side electrodes disposed on a back side of the first base material, having conductive properties, and made of an elastomer, and a protective layer disposed on a front side of the plurality of first front-side electrodes, having insulating properties, and made of an elastomer, and that detects approach and coordinates of an object to be detected, based on a change in capacitance between the first front-side electrode and the first back-side electrode which is caused by the approach of the object to be detected; and

a load sensor section that is disposed on a back side of the proximity sensor section, and that detects pressing and coordinates of the object to be detected, based on a load that is applied from the object to be detected via the proximity sensor section.

2. The hybrid sensor according to claim 1, wherein

the proximity sensor section detects the approach and the coordinates of the object to be detected, based on a decrease in the capacitance between the first front-side electrode and the first back-side electrode which is caused as capacitance is generated between the first front-side electrode and the object to be detected by the approach of the object to be detected.

3. The hybrid sensor according to claim 1, wherein

the load sensor section includes a second base material having insulating properties and made of an elastomer, a plurality of second front-side electrodes disposed on a front side of the second base material, having conductive properties, and made of an elastomer, and a plurality of second back-side electrodes disposed on a back side of the second base material, having conductive properties, and made of an elastomer, and detects the pressing and the coordinates of the object to be detected, based on an increase in capacitance between the second front-side electrode and the second back-side electrode which is caused as an interelectrode distance between the second front-side electrode and the second back-side electrode is decreased by the load.

4. The hybrid sensor according to claim 3, further comprising:

an intermediate layer disposed between the proximity sensor section and the load sensor section, having conductive properties, and being elastic and grounded.

5. The hybrid sensor according to claim 4, wherein

an insulating spacer having insulating properties and made of an elastomer is disposed on at least one of front and back sides of the intermediate layer.

6. The hybrid sensor according to claim 5, wherein

the insulating spacer has a load spread suppressing mechanism that suppresses spreading of the load in a planar direction.

7. The hybrid sensor according to claim 6, wherein

the load sensor section has a plurality of overlapping portions where the plurality of second front-side electrodes overlap the plurality of second back-side electrodes as viewed from a front side or a back side, and

the load spread suppressing mechanism is interposed between the overlapping portions that adjoin each other in the planar direction, as viewed from the front side or the back side.

8. The hybrid sensor according to claim 6, wherein

the load spread suppressing mechanism is a load spread suppressing groove that is formed in a front or back surface of the insulating spacer.

9. The hybrid sensor according to claim 6, wherein

the load spread suppressing mechanism is a load spread suppressing hole that extends through the insulating spacer in a front-back direction.

10. The hybrid sensor according to claim 3, wherein

the proximity sensor section includes a first front-side insulating layer disposed on the front side of the plurality of first front-side electrodes and made of an elastomer, and a first back-side insulating layer disposed on a back side of the plurality of first back-side electrodes and made of an elastomer,

the load sensor section includes a second front-side insulating layer disposed on a front side of the plurality of second front-side electrodes and made of an elastomer, and a second back-side insulating layer disposed on a back side of the plurality of second back-side electrodes and made of an elastomer, and

the hybrid sensor satisfies at least one of the following (a) and (b):

(a) in the proximity sensor section, the first front-side electrodes are printed on at least one of the first base material and the first front-side insulating layer, and the first back-side electrodes are printed on at least one of the first base material and the first back-side insulating layer; and

(b) in the load sensor section, the second front-side electrodes are printed on at least one of the second base material and the second front-side insulating layer, and the second back-side electrodes are printed on at least one of the second base material and the second back-side insulating layer.

11. The hybrid sensor according to claim 1, wherein

at least one of a protruding portion and a recessed portion is disposed on a surface of the protective layer.