JP2798069B2 - Skin impedance input device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a skin impedance measuring device, and more particularly to a skin impedance input device.

[0002]

2. Description of the Related Art Studies have been made on using the skin impedance of a living body as an index of arousal level. In order to measure this kind of skin impedance, for example, a measuring device of an AC conduction method shown in FIG. 14 is used. Here, the electrodes for measurement are a measurement electrode EL ₁ , a current-carrying electrode EL _2, and a reference electrode EL.
Are used three electrodes R, the palm of the hand measurement electrodes EL _1, and energizing the electrode EL _2, a reference electrode ELR attached to the forearm. The output voltage from the sine wave oscillator 1 is converted into an in-phase current by the voltage / current converter 2 and the skin is energized. The change in skin impedance is extracted as a potential drop by the current, and is amplified by the differential amplifier 3. This is synchronously rectified by a multiplier 4 using a reference signal, and a component having a frequency component twice that of the reference signal is removed through a low-pass filter (LPF) 5 having a cutoff frequency of 3.5 Hz.
A DC signal is extracted from the F output, and a voltage (SIL) proportional to the equivalent series resistance component R of the skin impedance Z is obtained.
Becomes Further, this SIL is cut off at a frequency of 0.05 Hz.
By passing through a high-pass filter 6, a waveform (SIR) proportional to the fluctuation component of skin impedance can be extracted [Reference: IEICE Technical Report MBE]
-54 (1993-07), Electron Theory C113, Vol. 7, 1993 P527].

[0003]

In the above-described conventional methods for measuring skin impedance, there is no sufficient suggestion regarding the location of the electrode and the change in the contact state.
Therefore, for example, the electrode arrangement for measuring the skin impedance of the palm of the hand and the contact conditions between the electrode and the skin are not known, and the measurement reliability, data interpretation, and reproducibility are insufficient. There is.

[0004] In general, there is a pregel electrode as an electrode when a current is applied to a living body for measurement. This pregel electrode has the merit of ensuring the degree of adhesion to the skin and enables stable measurement, but has problems in durability, feeling of contact with the skin, and workability. The present invention has been made in view of the above problems, and provides a skin impedance input device having electrodes capable of performing stable measurement and having excellent durability, contact with skin, and excellent workability. It is an object.

[0005]

Means for Solving the Problems The inventors of the present application have
As shown in FIG. 3, using the conventional energizing device shown in FIG.
And three electrodes on the palm, namely the measuring electrode EL₁, Energizing
Extreme EL_TwoAnd the reference electrode ELR, and the current I₁Energize
The output V of the differential amplifier 3 is
_OUTIs the measurement electrode EL₁Contact resistance R in₁In
Only heavily dependent. The following shows the reason
Referring to the equivalent circuit of the E portion of FIG. 3 (FIG. 13),
explain.

Here, in the circuit of FIG. 3, the voltage / current converter 2 has a built-in current servo function for maintaining a target current value represented by an input voltage value. Therefore, even if the contact resistance variation between the current supply electrode EL ₂ and the skin, the value of the current crowded flowed into the hands through the energizing electrode EL ₂ is due to the operation of the current servo function, unchanged.
The voltage / current converter 2 is in a state which gave this current servo function, for example to pass the contact area of the powered electrode EL ₂ and is extremely small constant current, that the infinitely output voltage increases To prevent this, a voltage limiter is built in.

[0007] The input impedance of the differential amplifier 3 is very large and can be regarded as substantially infinite. From the above, the circuit of the portion E in FIG. 3 can be represented by the equivalent circuit in FIG. Incidentally, R ₁ is the contact resistance between the measuring electrode EL ₁ and the skin, R ₂ is the contact resistance between the powered electrode EL ₂ and the skin, R _R is the contact resistance between the reference electrode ELR and the skin (internal resistance of the hand The value was 0).

In this equivalent circuit, the following circuit equation is established. -V _OUT = V _R -V ₀ (1) V _T = R ₁ · I ₁ + V ₀ (2) V _R = V _T (3) Equation (3) holds for the differential amplifier 3. since the input impedance of infinity, a resistor R _R current is because not flow.

From the above equations (1) to (3), -V _OUT = R ₁ · I ₁ (4) and R ₁ = ρ · S ₁ (5) Therefore, the equation (4) can be transformed into -V _OUT = ρ · S ₁ · I ₁ (6).

Therefore, the output V _OUT is affected only by the skin contact resistance R ₁ , that is, the skin contact resistance of the measuring electrode EL ₁ , and an attempt is made to obtain an output V _OUT correctly corresponding to the skin contact resistance ρ per unit area. if it is necessary to keep the contact area S ₁ stably. The invention of this application has been made based on the above-described findings, and in the skin impedance input device, a constant contact area is obtained between the measurement electrode and the skin so that measurement can be performed most stably. It is configured as follows.

A skin impedance input device according to claim 1 of the present specification is a device for measuring skin impedance using three electrodes of a measuring electrode, a conducting electrode and a reference electrode. Is
It is arranged so as to be in contact with the base of the thumb or the base of the fifth finger of the subject's hand. Further, the skin impedance input device according to claim 2 measures skin impedance using three electrodes of a measurement electrode, a conduction electrode, and a reference electrode, wherein the measurement electrode is a thumb electrode of a hand of a subject. The base is arranged so that the energizing electrode is in contact with the base of the fifth finger, and the reference electrode is so arranged as to be in contact with the palm region other than the base of the thumb and the base of the fifth finger.

According to a third aspect of the present invention, there is provided a skin impedance input device for measuring skin impedance using three electrodes of a measuring electrode, a conducting electrode and a reference electrode, wherein the measuring electrode is provided at a base of a fifth finger. The current-carrying electrode is arranged so as to contact the base of the thumb, and the reference electrode is arranged so as to contact the palm region other than the base of the thumb and the base of the fifth finger.

According to a fourth aspect of the present invention, there is provided a skin impedance input device for measuring skin impedance using three electrodes, a measuring electrode, a conducting electrode, and a reference electrode. At the base of the thumb, the reference electrode is arranged so as to contact the base of the fifth finger, and the energizing electrode is arranged so as to contact the palm base other than the base of the thumb and the base of the fifth finger. .

According to a fifth aspect of the present invention, there is provided a skin impedance input device for measuring skin impedance using three electrodes of a measuring electrode, a conducting electrode, and a reference electrode, wherein the measuring electrode is provided at a base of a fifth finger. The reference electrode is arranged so as to contact the base of the thumb, and the energizing electrode is arranged so as to contact the palm region other than the base of the thumb and the base of the fifth finger.

The skin impedance input device according to claim 6 is the first, second, third, or fourth aspect of the present invention.
Alternatively, in the device according to claim 5, the measurement electrode, the current-carrying electrode, and the reference electrode are formed on an upper surface of a base having a flat upper surface. A skin impedance input device according to a seventh aspect of the present invention is the skin impedance input device according to the sixth aspect, wherein the positioning means for positioning the palm of the hand at a predetermined position when the hand is placed on the upper surface of the base. It is provided above.

Further, the skin impedance input device according to claim 8 is the first, second, third, or fourth aspect of the present invention.
Alternatively, in the device according to claim 5, the measurement electrode, the current-carrying electrode, and the reference electrode are formed on a surface of a joystick-like substrate having a surface formed so that the palm surface of the hand fits the surface when gripped. It is. Claim 9
The game machine according to the third aspect uses the skin impedance input device according to the sixth, seventh or eighth aspect as an input means.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in more detail with reference to embodiments. FIG. 1 is a plan view showing a skin impedance input device according to an embodiment of the present invention.
In the skin impedance input device of this embodiment, a right hand handprint 11 is formed on the upper surface of a flat rectangular substrate 10, and when the subject places his right hand on the handprint 11 of the substrate 10, the thumb 21 b A where the base of
Measuring electrode EL ₁ is disposed, also the fifth finger (child finger) 25
position B to the reference electrode ELR which b the base of the contacts are arranged, further to the position C where the base of the second finger 22b~ fourth finger 24b in contact, the energizing electrode EL ₂ are arranged. Here, the base of the thumb is, for example, the thumb 21 of the left palm shown in FIG.
b and the area a of the area a bulging from the center of the palm extending between the wrist 26b and the base of the fifth finger is between the fifth finger 25b of the left palm and the wrist 26b shown in FIG. It is a part of a region b which is flat and bulges from the center of the palm. In FIG. 1, 21a,..., 25a are the thumbs,.

The measuring electrode EL ₁ has an elliptical shape having a major axis of about 20 mm and a minor axis of about 10 mm, and protrudes about 5 mm from the upper surface of the substrate 10. Other energizing electrode ELR and the reference electrode EL ₂ is also almost the same. In addition, a metal such as stainless steel or conductive rubber is used as an electrode material. On the upper surface of the substrate 10, when the person to be measured places the right hand on the handprint 11, the boss 12 comes to the thumb 21 and the fork of the second finger so that the palm of the hand is positioned. I have. Further, although in the substrate 10 is not shown, the measuring electrode EL _1, powered electrode EL _2, and the lead lines are provided to the reference electrode ELR is connected, when measuring the skin impedance, shown in FIG. 3 Connected to the circuit section of the measuring device. The circuit section is not particularly different from the conventional one. The substrate 10 is made of, for example, an electrical insulating material such as a resin. In this embodiment, the positioning boss 12 is located between the thumb and the second finger.
2 may be provided at another position, for example, between the second and third fingers. In this case, the boss 12 and the energizing electrode EL ₂ may be integrally formed. As described later, when the electrodes arranged at the bases of the second to fourth fingers are the reference electrodes ELR, the electrodes ELR and the boss 12 may be integrated.

When the subject measures the skin impedance, the right hand is placed on the substrate 10 so that the space between the thumb 21b and the second finger 22b hits the position of the boss 12. Thus, the entire measuring electrode EL ₁ is flattened and bulging area a
Since contact (see FIG. 4), and a predetermined electrode EL ₁ protrudes into the coin-like, do not change the contact area with respect to any body movement. Therefore, stable measurement is possible. Further, since the subject only needs to put his / her hand on the subject, there is no trouble and the restraint can be eased. Further, since the electrodes are made of metal, the feeling of contact, durability and workability are improved, and the application range of the skin impedance input device can be expanded.

As another embodiment, when the right hand is put on the bill 11 as shown in FIG. 5 instead of FIG. 1, the measurement electrode EL ₁ is placed at the position B where the base of the fifth finger 25b contacts.
1 and the reference electrode ELR is arranged at the position A where the base of the thumb 21b contacts, the same effect as the electrode arrangement of FIG. 1 can be obtained. Also, as in the case of FIG. 5, the measuring electrode EL ₁
At the position B where the base of the fifth finger 25b contacts, and the energizing electrode E at the position A where the base of the thumb 21b contacts.
The L ₂ is arranged, the reference electrode ELR may be disposed in the base of the second to fourth finger. Furthermore, as in the case of FIG. 1, with the measuring electrode EL ₁ is the base of the thumb 21b disposed at a position A in contact, the energizing electrode EL ₂ to position B where the base of the fifth finger 25b contacts disposed, the reference The electrode ELR may be arranged at the base of the second to fourth fingers. The measurement electrode EL ₁
Base of only the thumb 21b or placed at the base of the fifth finger 25b, another current electrode EL ₂ and the reference electrode ELR, is
Regardless of the position on the palm, stable measurement is possible.

FIG. 6 shows a left hand bill 1 on the upper surface of the substrate 10.
1, the measuring electrode EL _1, energizing electrode EL ₂ and the reference electrode EL
Is obtained by forming the R, similarly to FIG. 1, but arranged as the base of the thumb 21b comes into contact with the measuring electrode EL _1. As in the case of the right hand, various deformation arrangements can be considered in the case of the left hand. The measurement electrode EL ₁ is thumb 21b
If it is arranged so as to be in contact with the base of the second finger or the base of the fifth finger 25b, a sufficiently stable impedance can be measured, and the other energized electrodes EL ₂ and the reference electrode ELR are arranged in any area I can't wait. For example,
As shown in FIG. 7, the reference electrode ELR energization electrode EL ₂ 5
The finger 25b may be arranged so as to be in contact with the base of the finger 25b.

FIG. 8 is a perspective view showing a skin impedance input device according to another embodiment of the present invention. The skin impedance measuring apparatus according to this embodiment is of a joystick type, and has a substantially cylindrical base 30 with a curved surface 31 so that a palm and a finger fit when the subject grips the base with a hand. When the subject grasps the base 30, the palm surface comes into close contact with the surface of the base. The measurement electrode EL is placed at a position where the base of the thumb 21b contacts the surface of the base 30.
_1, also the reference electrode ELR a position proximal to the contact of the fifth finger 25b are further arranged conducting electrode EL ₂ at a position proximal of the second finger to the fourth finger 22b~25b contacts.

[0023] a Placing the skin impedance input device also measuring electrodes EL ₁ of the joystick-type base or the base of the fifth finger 25b of thumb 21b is required,
Other reference electrode ELR and the energizing electrode EL ₂ may be disposed in any region of the palm. As described above, in the embodiments described above, the base or the base of the fifth finger of the measuring electrode EL ₁ always thumb is in contact. This base Ai thumb of the palm that is flat and bulging in the base of the fifth finger, by contacting the measuring electrode EL _1, reduces the change in the contact area, fatal to the measurement state by poor contact This is to prevent any adverse effects.

Next, note that to reduce the change in the contact area of the measuring electrode EL ₁ mentioned above, other criteria electrode E
Change of the LR and the contact area of the powered electrode EL _2, illustrating a good reason it is not necessary to consider the words instability. 9 and 1
0 and FIG. 11 show the case where the input device of FIG. 1 is used for the energizing device shown in FIG. 3, and about half of only one electrode of the measuring electrode EL ₁ , the energizing electrode EL ₂ and the reference electrode ELR at the start of measurement. FIG. 11 is a characteristic diagram showing the absolute value SIL and the variation SIR of impedance when the palm of the hand is placed in a state where the area of the hand is covered with paper and the paper is rapidly pulled out when the measurement output is stabilized.

As shown in FIG. 9, when suddenly pull the paper measuring electrode EL _1, the absolute value SIL itself greatly changes the impedance, the influence to the measurement of the biological reaction change in the contact area as a disturbance I do. In contrast, the current-carrying electrode E
For L _2, almost no effect on the absolute value SIL impedance as shown in FIG. 10, small (short) and stabilizing delay of energization current of the circuit may be causing the output change pulse P is generated However, it is much shorter than the biological reaction period T (at least 2 seconds to several seconds at least) due to the paper being pulled out. In the case of the reference electrode ELR, FIG.
As shown in FIG. 1, there is almost no change in the output signal in both SIR and SIL.

FIG. 12 is a perspective view showing a game machine using the skin impedance input device of the embodiment shown in FIG. In this game machine, a player puts his / her left hand on a bill, thereby inputting skin impedance, capturing changes in skin impedance due to a difference in sweating state or the like, and performing a fortune-telling game, a psychological game, or the like. In this game machine, a handprint and three electrodes may be formed on the operation surface 41 of the game machine 40 by using the skin impedance input device 10.
May be inserted.

[0027]

[Effects of the Invention] Claims 1 and 2 in the claims of this application
According to the second, third, fourth, and fifth aspects of the present invention, the measurement electrode is disposed so as to be in contact with the base of the thumb or the base of the fifth finger, so that stable skin impedance is obtained. Can be measured, and a metal can be used as the electrode, so that the contact feeling, durability and workability can be improved, and the application range of skin impedance can be expanded.

Further, according to the invention of claim 6, since it is only necessary to place the palm on the upper surface of the planar base, measurement can be easily performed without restricting the subject. According to the seventh aspect of the present invention, the palm can be set at an appropriate position by the positioning means. Further, according to the invention according to claim 8, the measurement can be easily performed only by gripping with the hand.

According to the ninth aspect of the present invention, the skin impedance can be accurately input by a simple operation, that is, by putting a hand on a handprint or holding the hand, and a game can be enjoyed.

[Brief description of the drawings]

FIG. 1 is a plan view showing a skin impedance input device according to an embodiment of the present invention.

FIG. 2 is a diagram for explaining a base of a thumb and a base of a fifth finger of a palm;

FIG. 3 is a block diagram showing a circuit of an energization device for measuring palm skin impedance using the input device of FIG. 1;

FIG. 4 is a side view showing a state where a hand is placed on the skin impedance input device according to the embodiment.

FIG. 5 is a diagram showing another example of the electrode arrangement of the skin impedance input device.

FIG. 6 is a plan view showing a skin impedance input device for the left hand.

FIG. 7 is a diagram showing another example of the electrode arrangement of the skin impedance input device for the left hand.

FIG. 8 is a perspective view showing a skin impedance input device according to another embodiment of the present invention.

FIG. 9 is a diagram illustrating the energization output when half of the measurement electrode is covered with paper and the contact area is changed by suddenly removing the paper.

FIG. 10 is a diagram showing the energization output when half of the energization electrode is covered with paper, and the paper is suddenly removed to change the contact area.

FIG. 11 is a diagram showing the energization output when half of the reference electrode is covered with paper, and the paper is suddenly removed to change the contact area.

FIG. 12 is a perspective view of the game machine when the planar skin impedance input device is incorporated in the game machine.

FIG. 13 is a circuit diagram showing an equivalent circuit of a portion E of the circuit shown in FIG. 3;

FIG. 14 is a block diagram of an energizing device for explaining a conventional skin impedance measuring method using three electrodes.

[Explanation of symbols]

10 substrate (substrate) 11 bills 21a, ..., finger EL ₁ measuring electrode EL ₂ energization electrode ELR reference electrode 25a bills

Claims (9)

(57) [Claims] 1. A skin impedance input device for measuring skin impedance using three electrodes of a measuring electrode, a conducting electrode and a reference electrode, wherein at least the measuring electrode is at the base of the thumb or the fifth finger of the hand of the subject. A skin impedance input device, which is arranged so as to be in contact with a base of the skin impedance. 2. A skin impedance input device for measuring skin impedance using three electrodes of a measuring electrode, a conducting electrode, and a reference electrode, wherein the measuring electrode is connected to the base of the thumb of the hand of the subject. A skin impedance input device, wherein an electrode is arranged so as to contact a base of a fifth finger, and said reference electrode is arranged so as to contact a palm region other than a base of said thumb and a base of said fifth finger. 3. A skin impedance input device for measuring skin impedance using three electrodes of a measuring electrode, a conducting electrode and a reference electrode, wherein the measuring electrode is located at the base of a fifth finger, and the conducting electrode is located at the base of a thumb. The skin impedance input device, wherein the skin impedance input device is arranged so as to be in contact with the base electrode and the palm region other than the base of the thumb and the base of the fifth finger. 4. A skin impedance input device for measuring skin impedance using three electrodes, a measuring electrode, a conducting electrode, and a reference electrode, wherein the measuring electrode is provided at the base of the thumb of the hand of the subject. A skin impedance input device, wherein an electrode is arranged so as to be in contact with a base of a fifth finger, and said energizing electrode is arranged so as to be in contact with a palm region other than a base of said thumb and a base of said fifth finger. 5. A skin impedance input device for measuring skin impedance using three electrodes, a measuring electrode, a conducting electrode, and a reference electrode, wherein the measuring electrode is at a base of a fifth finger, and the reference electrode is at a base of a thumb. A skin impedance input device, wherein the current-carrying electrode is disposed so as to contact the palm region other than the base of the thumb and the base of the fifth finger. 6. The measuring electrode, the conducting electrode and the reference electrode,
6. The skin impedance input device according to claim 1, wherein the upper surface is formed on the upper surface of a planar substrate. 7. The skin impedance input device according to claim 6, further comprising positioning means for positioning the palm of the hand at a predetermined position when the hand is placed on the upper surface of the base. 8. The measuring electrode, the conducting electrode and the reference electrode,
The joystick is formed on the surface of a joystick-like base body whose surface is formed so that the palm surface of the hand fits the surface when gripped.
Or the skin impedance input device according to claim 5. 9. A game machine using the skin impedance input device according to claim 6, 7 or 8 as input means.