U.S. patent application number 15/448695 was filed with the patent office on 2017-10-19 for operation switch, dressing table and mirror using capacitance sensor.
The applicant listed for this patent is Panasonic Intellectual Property Management Co., Ltd. Invention is credited to YUKA HASEGAWA, KOUHEI KORESAWA, NORISHIGE NANAI, GOSUKE SAKAMOTO, TAKAAKI UKEDA.
Application Number | 20170302274 15/448695 |
Document ID | / |
Family ID | 60040196 |
Filed Date | 2017-10-19 |
United States Patent
Application |
20170302274 |
Kind Code |
A1 |
HASEGAWA; YUKA ; et
al. |
October 19, 2017 |
OPERATION SWITCH, DRESSING TABLE AND MIRROR USING CAPACITANCE
SENSOR
Abstract
An operation switch includes: a capacitance sensor that
generates three or more detection signals in response to approach
or contact of an object to respective three or more electrodes; a
determination circuit that determines whether or not the object is
a living body based on one or more detection signals selected from
the three or more detection signals, the one or more detection
signals excluding a detection signal having a maximum intensity
among the three or more detection signals; and a controller that,
when the object is determined to be a living body, generates an
operation signal for operating a predetermined device.
Inventors: |
HASEGAWA; YUKA; (Kanagawa,
JP) ; SAKAMOTO; GOSUKE; (Kyoto, JP) ;
KORESAWA; KOUHEI; (Kyoto, JP) ; NANAI; NORISHIGE;
(Osaka, JP) ; UKEDA; TAKAAKI; (Osaka, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Panasonic Intellectual Property Management Co., Ltd |
Osaka |
|
JP |
|
|
Family ID: |
60040196 |
Appl. No.: |
15/448695 |
Filed: |
March 3, 2017 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H03K 2217/960755
20130101; H03K 17/962 20130101; H03K 2017/9615 20130101; H03K
2217/960705 20130101 |
International
Class: |
H03K 17/96 20060101
H03K017/96 |
Foreign Application Data
Date |
Code |
Application Number |
Apr 14, 2016 |
JP |
2016-081538 |
Claims
1. An operation switch comprising: a capacitance sensor, including
three or more electrodes, configured to generate three or more
detection signals in response to approach or contact of an object
to the respective three or more electrodes; a determination circuit
that determines whether or not the object is a living body based on
one or more detection signals selected from the three or more
detection signals, the one or more detection signals excluding a
detection signal having a maximum intensity among the three or more
detection signals; and a controller that, when the object is
determined to be a living body, generates an operation signal for
operating a predetermined device.
2. The operation switch according to claim 1, wherein the one or
more detection signals further exclude a detection signal having a
minimum intensity among the three or more detection signals.
3. The operation switch according to claim 2, where the one or more
detection signals are a plurality of detection signals, and when an
average value of intensities of the plurality of detection signals
exceeds a threshold value, the determination circuit determines
that the object is a living body.
4. The operation switch according to claim 1, wherein the living
body is a human body.
5. The operation switch according to claim 1, wherein the
capacitance sensor further includes a reference electrode, and
generates a reference signal in response to approach or contact of
the object to the reference electrode, and the determination
circuit determines whether or not the object is a living body based
on the reference signal and the one or more detection signals.
6. The operation switch according to claim 1, wherein the
predetermined device is a light device, audio device, or air
conditioner.
7. The operation switch according to claim 1, wherein the
predetermined device is a light device, and the operation signal is
a signal for controlling light of the light device.
8. A dressing table comprising the operation switch according to
claim 1.
9. A mirror comprising the operation switch according to claim 1.
Description
BACKGROUND
1. Technical Field
[0001] The present disclosure relates to an operation switch, and a
dressing table and a mirror including the operation switch.
2. Description of the Related Art
[0002] A switch using a capacitance sensor has a simple structure
and can be increased in size. For this reason, the capacitance
sensor finds application in various products such as a touch switch
and a level switch. Even when water adheres to a capacitance
sensor, the sensor responds in the same manner as in the case where
a human touches the sensor. This causes malfunction.
[0003] On the other hand, for instance, Japanese Unexamined Patent
Application Publication No. 2009-239649 discloses a touch switch
sensing device that includes a touch switch unit having a plurality
of touch sensing electrodes that detect contact with a user and a
plurality of water sensing electrodes that detect contact with a
water droplet. The touch switch sensing device determines whether
an operation has been performed by a human, using the touch sensing
electrodes and the water sensing electrodes.
SUMMARY
[0004] In one general aspect, the techniques disclosed here feature
an operation switch including: a capacitance sensor, including
three or more electrodes, configured to generate three or more
detection signals in response to approach or contact of an object
to the respective three or more electrodes; a determination circuit
that determines whether or not the object is a living body based on
one or more detection signals selected from the three or more
detection signals, the one or more detection signals excluding a
detection signal having a maximum intensity among the three or more
detection signals; and a controller that, when the object is
determined to be a living body, generates an operation signal for
operating a predetermined device.
[0005] Additional benefits and advantages of the disclosed
embodiments will become apparent from the specification and
drawings. The benefits and/or advantages may be individually
obtained by the various embodiments and features of the
specification and drawings, which need not all be provided in order
to obtain one or more of such benefits and/or advantages.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] FIG. 1 is a front view of a dressing table including an
operation switch according to a first embodiment;
[0007] FIG. 2 is a block diagram illustrating the configuration of
the operation switch according to the first embodiment;
[0008] FIG. 3 is a schematic diagram schematically illustrating an
example of use of the operation switch according to the first
embodiment;
[0009] FIG. 4A is a plan view a capacitance type sensor included in
the operation switch according to the first embodiment;
[0010] FIG. 4B is a sectional view, taken along line IVB-IVB of
FIG. 4A, of the capacitance type sensor according to the first
embodiment;
[0011] FIG. 5A is a plan view schematically illustrating the manner
in which a water droplet adheres to an operation switch in related
art;
[0012] FIG. 5B is a graph for explaining the operation of the
operation switch in related art;
[0013] FIG. 6A illustrates plan views schematically illustrating
the manner in which a water droplet adheres to the operation switch
according to the first embodiment and the manner in which the
operation switch is operated with fingers;
[0014] FIG. 6B illustrates graphs for explaining the operation of
the operation switch according to the first embodiment;
[0015] FIG. 6C illustrates graphs for explaining the operation of
the operation switch according to a modification of the first
embodiment;
[0016] FIG. 7 is a block diagram illustrating the configuration of
an operation switch according to a second embodiment;
[0017] FIG. 8 is a side view of a dressing table including the
operation switch according to the second embodiment;
[0018] FIG. 9 is a plan view of a mirror including the operation
switch according to the modification; and
[0019] FIG. 10 is a sectional view, taken along line X-X of FIG. 9,
of the mirror according to the modification.
DETAILED DESCRIPTION
[0020] Hereinafter, embodiments will be specifically described with
reference to the drawings.
[0021] It is to be noted that each of the embodiment described
below illustrates a general or specific example. The numerical
values, shapes, materials, structural components, the arrangement
and connection of the structural components, steps, the sequence of
the steps shown in the following embodiments are mere examples, and
are not intended to limit the scope of the present disclosure. In
addition, among the structural components in the subsequent
embodiment, components not recited in any one of the independent
claims which indicate the broadest concepts are described as
arbitrary structural components.
[0022] It is to be noted that the respective figures are schematic
diagrams and are not necessarily precise illustrations. Therefore,
for instance, the scales used in the figures are not necessarily
the same. Furthermore, in the respective figures, the same
reference sign is given to substantially identical components, and
overlapping description is omitted or simplified.
First Embodiment
[0023] [1. General Outline]
[0024] First, the general outline of an operation switch 1
according to a first embodiment will be described using FIG. 1.
[0025] FIG. 1 is a front view of a dressing table 100 including an
operation switch 1 according to this embodiment. As illustrated in
FIG. 1, a dressing table 100 is a bathroom vanity including a
mirror 110, a frame 111 provided with the mirror 110, and a wash
stand 120. The dressing table 100 further includes an operation
switch 1 and a device 2.
[0026] The operation switch 1 generates an operation signal for
operating the device 2, and controls the device 2 by the generated
operation signal. The operation switch 1 detects approach or
contact of a detection target, and when the detection target is a
living body such as a finger or a hand of a user, the operation
switch 1 controls the device 2. The operation switch 1 performs,
for instance, on/off control of the device 2. It is noted that the
term "approach" in the present disclosure means a state of being
within a predetermined distance from an electrode.
[0027] As illustrated in FIG. 1, the operation switch 1 is provided
in the frame 111. It is to be noted that the position at which the
operation switch 1 is provided is not limited to this. The
operation switch 1 may be provided in the mirror 110 or the wash
stand 120.
[0028] The device 2 is, for instance, a lighting device provided in
the dressing table 100. Lighting on and lighting off or modulating
light of the device 2 is controlled by an operation signal
transmitted from the operation switch 1. It is to be noted that the
device 2 is not limited to a lighting device, and may be an
electrical equipment such as an audio equipment, an
air-conditioning equipment.
[0029] Hereinafter, the configuration of the operation switch 1
will be described using FIG. 2 and FIG. 3.
[0030] FIG. 2 is a block diagram illustrating the configuration of
the operation switch 1 according to this embodiment. FIG. 3 is a
schematic diagram schematically illustrating an example of use of
the operation switch 1 according to the first embodiment. As
illustrated in FIG. 2 and FIG. 3, the operation switch 1 includes a
capacitance type sensor 10, a determination circuit 20, and a
controller 30.
[0031] The capacitance type sensor 10 has three or more detection
electrodes 12, and detects approach or contact of a detection
target by detecting a capacitance with the detection electrodes 12.
The detection target includes a living body including a human body,
and water. Specifically, the detection target includes a detection
target to be detected correctly, such as a finger 3 illustrated in
FIG. 3, and a detection target such as a water droplet 4 (see FIG.
6A), dew condensation, vapor which may cause malfunction of the
device 2.
[0032] In this embodiment, as illustrated in FIG. 3, the
capacitance type sensor 10 is installed in the back side of the
frame 111 of the dressing table 100. Specifically, the capacitance
type sensor 10 is disposed such that a sensor surface (the major
surface of a substrate 11 described later) is approximately
vertical (that is, longitudinal arrangement).
[0033] When the human finger 3 as a detection target approaches or
comes into contact with the detection electrodes 12, each of the
three or more detection electrodes 12 of the capacitance type
sensor 10 outputs a detection signal indicating capacitance change
which occurs between the detection electrode and the fingers 3. The
configuration of the capacitance type sensor 10 will be described
later.
[0034] The determination circuit 20 determines whether or not the
detection target is a living body based on other one or more
detection signals excluding a signal having a maximum intensity,
out of detection signals outputted from the three or more detection
electrodes 12. The detailed operation of the determination circuit
20 will be described later.
[0035] When the detection target is determined to be a living body
by the determination circuit 20, the controller 30 generates an
operation signal for operating the device 2. The controller 30
transmits the generated operation signal to the device 2, thereby
controlling the device 2.
[0036] It is to be noted that the controller 30 and the device 2
can communicate via a wire or wirelessly. It is to be noted that
the determination circuit 20 and the controller 30 are implemented
by, for instance, a microcomputer (or a microprocessor).
Specifically, the determination circuit 20 and the controller 30
are implemented by components including a non-volatile memory in
which predetermined programs are stored, a volatile memory which is
a temporary storage area for executing the programs, an
input/output port, and a processor that executes the programs.
[0037] [2. Capacitance Type Sensor]
[0038] Subsequently, the details of the configuration of the
capacitance type sensor 10 according to this embodiment will be
described using FIG. 4A and FIG. 4B.
[0039] FIG. 4A is a plan view a capacitance type sensor 10 included
in the operation switch 1 according to this embodiment. FIG. 4B is
a sectional view, taken along line IVB-IVB of FIG. 4A, of the
capacitance type sensor 10 according to this embodiment.
[0040] As illustrated in FIG. 4A and FIG. 4B, the capacitance type
sensor 10 includes a substrate 11, and seven detection electrodes
12a to 12g formed in the substrate 11. It is to be noted that the
number of detection electrodes is not limited to seven, and may be
three or more.
[0041] The substrate 11 is, for instance, a resin substrate
composed of a resin material or a metal base substrate covered with
insulation. It is to be noted that although the substrate 11 is,
for instance, circular in plan view, but is not limited to this and
may be rectangular.
[0042] The detection electrodes 12a to 12g are each formed in one
surface of the substrate 11 in a predetermined pattern as
illustrated in FIG. 4B using, for instance, metal material such as
copper or silver. Specifically, the detection electrodes 12a to 12g
are each a solid electrode having a circular plan view, and are
equivalent in shape and size. The size of each of the detection
electrodes 12a to 12g is, for instance, larger than a water droplet
and smaller than a finger or a palm. Specifically, the size of each
of the detection electrodes 12a to 12g is 0.5 cm or greater and 10
cm or less in diameter.
[0043] It is to be noted that each of the detection electrodes 12a
to 12g is not limited to circular in plan view and may be
rectangular. Also, the detection electrodes 12a to 12g may be
different in shape and size.
[0044] In this embodiment, as illustrated in FIG. 4A, seven
detection electrodes 12a to 12g are disposed two-dimensionally in a
predetermined area in plan view. The predetermined area is, for
instance, a circular area, and corresponds to the major surface of
the substrate 11. The predetermined area (major surface of the
substrate 11) is an area larger than a finger or a palm, for
instance. Specifically, the size of the predetermined area is, for
instance, 1 cm or greater and 20 cm or less in diameter.
[0045] In this embodiment, as illustrated in FIG. 4A, the detection
electrode 12g is located in the center of the circular substrate
11, and six detection electrodes 12a to 12f are located around the
detection electrode 12g at evenly spaced intervals (at evenly
spaced angles) in a surrounding manner. It is to be noted that the
arrangement of the seven detection electrodes 12a to 12g is not
limited to this, and may be arranged in a matrix form or a linear
form, for instance.
[0046] It is to be noted that the seven detection electrodes 12a to
12g have the same structure, and differ only in the position within
the substrate 11. For this reason, in the following description,
the detection electrodes 12a to 12g are denoted by the detection
electrode 12 unless distinction is particularly necessary.
[0047] Each of the three or more detection electrodes 12 outputs a
detection signal indicating capacitance change which occurs between
a detection target and the detection electrode. For instance, as
illustrated in FIG. 3, when the finger 3 approaches or comes into
contact with the detection electrode 12, a capacitance occurring
between the detection electrode 12 and the finger 3 is increased,
and thus the intensity of a detection signal from the detection
electrode 12 is increased. The determination circuit 20 determines
whether or not the detection target is a living body (finger 3)
based on detection signals from the three or more detection
electrodes 12.
[0048] [3. Operation]
[0049] Next, the operation of the operation switch 1 according to
this embodiment as well as background to the present disclosure
will be described. First, the problem of an operation switch in
related art will be described using FIG. 5A and FIG. 5B. FIG. 5A is
a plan view schematically illustrating the manner in which a water
droplet 4 adheres to an operation switch 1x in related art. FIG. 5B
is a graph for explaining the operation of the operation switch 1x
in related art.
[0050] As illustrated in FIG. 5A, the operation switch 1x in
related art includes only one detection electrode 12x. The
operation switch 1x in related art generates an operation signal
when the intensity of a detection signal outputted from the
detection electrode 12x exceeds a predetermined threshold value
th.
[0051] When a water droplet 4 adheres to the detection electrode
12x, the capacitance between the detection electrode 12x and the
water droplet 4 is increased, and thus the intensity of a detection
signal is increased. As illustrated in FIG. 5B, when the intensity
of a detection signal exceeds a threshold value th, an operation
signal is generated to cause the device 2 to be operated.
[0052] Since the operation switch 1x in related art is provided
with only one detection electrode 12x like this, there is a problem
in that the water droplet 4 and the human finger 3 cannot be
distinguished, and even when the water droplet 4 adheres to the
detection electrode 12x, the device 2 is caused to be operated.
[0053] FIG. 6A illustrates plan views schematically illustrating
the manner (a) in which the water droplet 4 adheres to the
operation switch 1 according to this embodiment and the manner (b)
in which the operation switch 1 is operated with the finger 3. FIG.
6B illustrates graphs for explaining the operation of the operation
switch 1 according to this embodiment.
[0054] As illustrated in FIG. 6A (a), the water droplet 4 comes
into contact with the detection electrode 12f at time t1.
Therefore, as illustrated in FIG. 6B (a), at time t1, the intensity
of a detection signal DS6 from the detection electrode 12f is
increased and exceeds the threshold value th.
[0055] In this embodiment, the determination circuit 20 determines
whether or not the detection target is a living body based on other
one or more detection signals excluding a signal having a maximum
intensity, out of detection signals DS1 to DS7 outputted from the
seven detection electrodes 12a to 12g, respectively. Specifically,
when the intensity of an average signal obtained by averaging the
other one or more detection signals exceeds the threshold value th,
the determination circuit 20 determines that the detection target
is a living body.
[0056] In the example illustrated in FIG. 6B (a), the intensity of
the detection signal DS6 has a maximum at time t1. The
determination circuit 20 determines whether or not the detection
target is a living body based on all remaining detection signals
DS1 to DS5 and DS7 excluding the detection signal D6 having a
maximum intensity, out of the detection signals DS1 to DS7.
Specifically, as illustrated in FIG. 6B (b), the determination
circuit 20 generates an average signal AS by averaging the
intensities of the detection signals DS1 to DS5 and DS7. Since the
case has been described in which all the intensities of the
detection signals DS1 to DS5 and DS7 are the same, the average
signal AS is the same as the detection signal DS1 illustrated in
FIG. 6B.
[0057] As illustrated in FIG. 6B (b), at time t1, the intensity of
the average signal AS does not exceeds the threshold value th, and
thus the determination circuit 20 determines that the detection
target is not a living body. Thus, the controller 30 does not
generate an operation signal.
[0058] Next, as illustrated in FIG. 6A (b), at time t2, the finger
3 of a user approaches or comes into contact with a plurality of
detection electrodes 12 so as to cover the detection electrodes 12.
For this reason, as illustrated in FIG. 6B (a), at time t2, the
intensities of the detection signals DS1 to DS5 and DS7 from the
remaining detection electrodes 12a to 12e and 12g are increased.
Although for the detection signal DS6 if not saturated, the
intensity is increased, here, the case is illustrated in which the
intensity is not increased.
[0059] At time t2, the intensities of the remaining detection
signals DS1 to DS5 and DS7 are increased, and thus the intensity of
the average signal AS is also increased as illustrated in FIG. 6B
(b). The intensity of the average signal AS exceeds the threshold
value th, and thus the determination circuit 20 determines that the
detection target is a living body. Thus, the controller 30
generates an operation signal, and the device 2 is operated.
[0060] As described above, even when the water droplet 4 adhered to
one of the seven detection electrodes 12a to 12g, an operation
signal is not generated, and thus it is possible to avoid
malfunction of the device 2. When the finger 3 approaches and
covers all (or the most part) of the seven detection electrodes 12a
to 12g, an operation signal is generated, and thus the device 2 can
be operated according to the intention of a user.
Modification of First Embodiment
[0061] Hereinafter, a modification of the first embodiment will be
described.
[0062] In this modification, the determination circuit 20
determines whether or not the detection target is a living body
based on other one or more detection signals excluding a signal
having a maximum intensity and a signal having a minimum intensity,
out of detection signals outputted from the three or more detection
electrodes 12. That is, the modification differs from the first
embodiment in that not only a signal having a maximum intensity but
also a signal having a minimum intensity are excluded.
[0063] In the example illustrated in FIG. 6B, in order to
facilitate description, all the intensities of the detection
signals DS1 to DS5 and DS7 follow the same behavior. Practically,
the rates of increase in the intensities of the detection signals
DS1 to DS5 and DS7 are varied depending on the distance to the
finger 3. For instance, in the example illustrated of FIG. 6A (b),
the detection electrode 12b is away from the finger 3. Thus, as
illustrated in FIG. 6C (a), the intensity of the detection signal
DS2 from the detection electrode 12b is not increased so much. FIG.
6C illustrates graphs for explaining the operation of the operation
switch 1 according to this modification.
[0064] It is to be noted that as a comparative example, FIG. 6C (b)
illustrates an average signal AS2 in the case where only the
detection signal DS6 having a maximum intensity is excluded as in
the first embodiment. Since the detection signal DS2 is used for
calculation of the average signal AS2, the intensity of the average
signal AS2 at time t2 is lower than an average signal AS1. Thus,
the intensity of the average signal AS2 may not exceed the
threshold value th, and an operation signal may not be generated.
In this case, although a user operates the operation switch 1, the
device 2 won't be operated.
[0065] On the other hand, in this modification, the determination
circuit 20 determines whether or not the detection target is a
living body based on the remaining detection signals DS1, DS3 to
DS5 and DS7 excluding the detection signal DS6 having a maximum
intensity and the detection signal DS2 having a minimum intensity.
Specifically, the determination circuit 20 generates the average
signal AS1 by averaging the intensities of the detection signals
DS1, DS3 to DS5 and DS7. As illustrated in FIG. 6C (b), the
intensity of the average signal AS1 exceeds the threshold value th
at time t2, and thus an operation signal is generated.
[0066] As described above, with the operation switch 1 according to
this modification, even when one detection electrode 12 (for
instance, the detection electrode 12b) is unable to detect approach
of the finger 3 and the intensity of a detection signal is not
increased, a detection signal having a minimum intensity is
excluded and is not used for determination as to whether or not the
detection target is a living body. Therefore, the accuracy of
determination as to whether or not the detection target is a living
body is increased, and thus it is possible to avoid malfunction of
the device 2. It is to be noted that not only the case where
approach of the finger 3 is undetectable, but also the case where
the sensitivity is decreased due to failure of one detection
electrode 12, it is possible to avoid malfunction of the device
2.
Second Embodiment
[0067] Next, the operation switch according to a second embodiment
will be described using FIG. 7 and FIG. 8.
[0068] FIG. 7 is a block diagram illustrating the configuration of
an operation switch 201 according to this embodiment. FIG. 8 is a
side view of a dressing table 100 including the operation switch
201 according to this embodiment.
[0069] As illustrated in FIG. 7, the operation switch 201 according
to this embodiment differs from the operation switch 1 according to
the first embodiment illustrated in FIG. 2 in that instead of the
determination circuit 20, a determination circuit 220 is provided
and a reference electrode 212 is newly provided. Hereinafter, the
difference from the first embodiment will be described, and
description of the same point is omitted or simplified.
[0070] The reference electrode 212 and the detection electrode 12
have the same configuration. That is, the reference electrode 212
outputs a detection signal for reference (in short, a reference
signal) that indicates change in the capacitance generated between
a detection target and the reference electrode 212. The detection
target of the reference electrode 212 is the same as the detection
target of the detection electrode 12, that is, a living body
including a human body, and water.
[0071] The reference electrode 212 is disposed at a position away
from the three or more detection electrodes 12. Specifically, the
reference electrode 212 is disposed at a position which allows
detection of approach or contact of a user 5 who operates the
operation switch 201, and to which water is less likely to adhere
compared with the detection electrode 12.
[0072] For instance, as illustrated in FIG. 8, the reference
electrode 212 is disposed at a front portion of the wash stand 120.
When the user 5 utilizes the dressing table 100, the user 5
normally stands in front of the dressing table 100. Thus, the
intensity of a detection signal for reference from the reference
electrode 212 is increased due to approach of the waist, legs,
knees of the user 5.
[0073] The determination circuit 220 determines whether or not the
detection target is a living body based on other one or more
detection signals excluding a detection signal having a maximum
intensity and a detection signal for reference from the reference
electrode 212, out of detection signals from the three or more
detection electrodes 12 of the capacitance type sensor 10.
[0074] Specifically, similarly to the first embodiment, when the
intensity of a detection signal for reference exceeds a
predetermined threshold value, the determination circuit 220 makes
determination as to the average signal and the threshold value th.
It is to be noted that a threshold value used for determination of
the detection signal for reference may be the same as or different
from the threshold value th used for determination of the average
signal.
[0075] Also, when the intensity of the detection signal for
reference does not exceed a predetermined threshold value, the
determination circuit 220 makes no determination as to the average
signal and the threshold value th. Thus, when the intensity of the
detection signal for reference does not exceed a predetermined
threshold value, even if the intensity of the average signal
exceeds the threshold value, the determination circuit 220 does not
determine that the detection target is a living body. For this
reason, when the intensity of the detection signal for reference
does not exceed a threshold value, an operation signal is not
outputted and the device 2 is not controlled. Even if the
capacitance type sensor 10 detects a detection target in conditions
where an operation of the user 5 is unlikely to be performed, for
instance, when the user 5 is not standing in front of the dressing
table 100, an operation signal is not outputted. Thus, it is
possible to avoid malfunction of the device 2.
[0076] It is to be noted that arrangement of the reference
electrode 212 is not limited to the aforementioned example. For
instance, the reference electrode 212 may be provided in frame 111
or the mirror 110. In this case, eaves may be provided above the
reference electrode 212 so that a water droplet does not adhere to
the reference electrode 212.
Other Embodiments
[0077] Although the operation switch according to one or more
aspects has been described based on the embodiments so far, the
present disclosure is not limited to these embodiments. The
embodiments to which various alterations which will occur to those
skilled in the art are made, and an embodiment constructed by a
combination of components of different embodiments without
departing from the spirit of the present disclosure are also
included within the scope of the present disclosure.
[0078] For instance, in the embodiments, as the detection target
which may cause malfunction of the device 2, a water droplet, dew
condensation, vapor have been mentioned. However, the detection
target is not limited to these. Also, as the detection target to be
detected correctly, a finger, a palm of a user have been mentioned.
However, the detection target to be detected correctly is not
limited to these. The detection target may be any object, as long
as the capacitance changes between the detection electrode 12 and
the object.
[0079] For instance, the determination circuit 20 may exclude not
only a signal having a maximum intensity, but also a signal having
the second highest intensity. In other words, the determination
circuit 20 may exclude signals having the 1st to nth highest
intensity, where n is a number smaller than the number of detection
electrodes 12 included in the capacitance type sensor 10. The same
goes with the case where a minimum signal is excluded.
[0080] For instance, in the embodiments, comparison is made between
the threshold value th and the intensity of an average signal
obtained by averaging the remaining detection signals excluding a
detection signal having a maximum intensity. However, without being
limited to this, for instance, weighted addition with increased
weight of the detection signal DS7 may be performed so that the
detection electrode 12g located in the center is assigned high
importance.
[0081] For instance, in the embodiments, the example has been
illustrated in which the operation switch 1 is provided in the
frame 111 of the mirror 110. However, the mirror 110 may include
the operation switch 1.
[0082] FIG. 9 is a plan view of a mirror 110a including the
operation switch 1 according to this modification. FIG. 10 is a
sectional view, taken along line X-X of FIG. 9, of the mirror 110a
according to this modification.
[0083] As illustrated in FIG. 10, the mirror 110a includes a
transparent layer 111a that allows visible light to pass through,
and a reflective metal layer 111b that reflects visible light. The
transparent layer 111a is, for instance, a glass substrate. The
reflective metal layer 111b is formed by depositing a metal film
such as silver or aluminum on the surface of the glass substrate.
The surface (surface facing the transparent layer 111a) of the
reflective metal layer 111b is a specular surface. Thus, the mirror
110a can reflect the figure of a user. It is to be noted that a
non-conductive material (for instance, a half mirror) may be used
for the reflective metal layer 111b. In this case, the capacitance
type sensor 10 may be disposed without machining the specular
surface.
[0084] As illustrated in FIG. 9, the operation switch 1 is provided
in part of the mirror 110a. Specifically, as illustrated in FIG.
10, the capacitance type sensor 10 of the operation switch 1 is
disposed in an opening 111c provided in part of the reflective
metal layer 111b. In other words, the metal layer, facing the
sensor surface, of the capacitance type sensor 10 is removed. Thus,
the detection electrode 12 of the capacitance type sensor 10 can
detect a finger which comes into contact with or approaches the
transparent layer 111a.
[0085] It is to be noted that similarly to the embodiments, the
operation switch 1 controls the device 2 (not illustrated in FIG. 9
and FIG. 10). For instance, when the mirror 110a is installed at a
predetermined position, the controller 30 is connected to a light
fixture or the like located nearby to control the light fixture.
Alternatively, for the purpose of preventing fog of the mirror
110a, the back surface (the surface facing the reflective metal
layer 111b) of the mirror 110a may be provided with an electrically
heated wire or the like. The operation switch 1 may control
supplying and stopping of power to the electrically heated wire. In
other words, the operation switch 1 may be a switch that switches
between ON/OFF of fog prevention function of the mirror 110a.
[0086] Various modifications, replacements, additions, and
omissions may be made to the embodiments described above within the
scope of the claims and the scope of the equivalents thereof.
Overview of Embodiments
[0087] The operation switch according to an aspect of the present
disclosure includes: a capacitance type sensor having three or more
detection electrodes, each of which outputs a detection signal
indicating change in the capacitance generated between a detection
target and the detection electrode; a determination circuit that
determines whether or not the detection target is a living body
based on other one or more detection signals excluding a signal
having a maximum intensity, out of detection signals outputted from
the three or more detection electrodes; and a controller that, when
the detection target is determined to be a living body by the
determination circuit, generates an operation signal for operating
a predetermined device.
[0088] Thus, for instance, even when a small detection target such
as a water droplet approaches or comes into contact with one
detection electrode, and the intensity of a detection signal from
the detection electrode is increased, the detection signal is
excluded, and is not used for determination as to whether or not
the detection target is a living body. Therefore, the accuracy of
determination as to whether or not the detection target is a living
body is increased, and thus it is possible to avoid malfunction of
the device.
[0089] For instance, the determination circuit may determine
whether or not the detection target is a living body based on other
one or more detection signals excluding a signal having a maximum
intensity and a signal having a minimum intensity, out of detection
signals outputted from the three or more detection electrodes.
[0090] For instance, when the sensitivity of one detection
electrode is reduced due to a failure or the like, even if a hand
of a user approaches or comes into contact with the detection
electrode, the intensity of a detection signal from the detection
electrode is not increased. Depending on the position of a hand of
a user, a situation may occur in which the one detection electrode
is unable to detect approach of a hand, and thus the intensity of a
detection signal is not increased. In this case, with the operation
switch according to this aspect, a detection signal having a
minimum intensity is excluded, and is not used for determination as
to whether or not the detection target is a living body. Therefore,
the accuracy of determination as to whether or not the detection
target is a living body is increased, and thus it is possible to
avoid malfunction of the device.
[0091] For instance, when the intensity of an average signal
obtained by averaging the other one or more detection signals
exceeds a threshold value, the determination circuit may determine
that the detection target is a living body.
[0092] Thus, by averaging the remaining detection signals excluding
a detection signal having a maximum intensity, a variation between
the detection signals can be reduced. Therefore, the accuracy of
determination as to whether or not the detection target is a living
body is increased, and thus it is possible to avoid malfunction of
the device.
[0093] For instance, the detection target may include a living body
including a human body, and water.
[0094] Thus, for instance, when a water droplet adheres to one
detection electrode, the intensity of a detection signal from the
detection electrode to which a water droplet has adhered is
increased, and thus the detection signal is excluded. Since the
intensity of a detection signal from each of the remaining
detection electrodes remains low, an operation signal for operating
the device is not generated. On the other hand, for instance, when
a user puts its finger or palm closer to the operation switch to
operate it, the intensities of detection signals from all the three
detection electrodes (or the most part) are increased. Therefore,
the intensities of the remaining detection signals excluding a
signal having a maximum intensity are also increases, and thus an
operation signal is generated. In this manner, with the operation
switch according to this aspect, the accuracy of determination as
to whether the detection target is water or human is increased, and
thus it is possible to avoid malfunction of the device.
[0095] For instance, the operation switch according to an aspect of
the present disclosure may further include a reference electrode
that is disposed at a position away from the three or more
detection electrodes, and that outputs a detection signal
indicating change in the capacitance generated between the
detection target and the detection electrode. The determination
circuit may determine whether or not the detection target is a
living body based on the other one or more detection signals and
the detection signal for reference.
[0096] Thus, for instance, the reference signal from a reference
electrode indicates approach or contact of a detection targets
other than water, and thus the accuracy of determination as to
whether the detection target is water or human is increased. Thus,
with to the operation switch according to this aspect, it is
possible to avoid malfunction of the device.
[0097] The dressing table according to an aspect of the present
disclosure includes the operation switch.
[0098] Thus, the operation switch is included, and it is possible
to avoid malfunction of the device. The dressing table according to
this aspect is particularly useful when utilized for a bathroom
vanity to which water is likely to adhere, for instance.
[0099] The present disclosure can be utilized for an operation
switch that can avoid malfunction of the device, and is applicable
to various switches used in, for instance, a bathroom, a wash
stand, a toilet, a kitchen, a dressing table to which a water
droplet is likely to adhere.
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