U.S. patent application number 10/098400 was filed with the patent office on 2002-08-01 for biological signal transmission apparatus.
This patent application is currently assigned to NIHON KOHDEN CORPORATION. Invention is credited to Hosaka, Hidehiro, Matsumura, Fumiyuki, Sakata, Hiroshi, Sekiguchi, Tetsushi.
Application Number | 20020103441 10/098400 |
Document ID | / |
Family ID | 26580800 |
Filed Date | 2002-08-01 |
United States Patent
Application |
20020103441 |
Kind Code |
A1 |
Matsumura, Fumiyuki ; et
al. |
August 1, 2002 |
Biological signal transmission apparatus
Abstract
An electrode 4 for detecting a biological signal and a loop
antenna 3 are integrally mounted on a support 2 placed on the
surface of a living body and a transmitter 5 is placed on the
support 2. A biological signal detected on the electrode 4 is input
through a connector 11 to electric circuitry 10 of the transmitter
5 and an electric signal processed by the electric circuitry 10 is
output through connectors 12 and 13 to both ends of the loop
antenna 3 from which the biological signal is emitted to a
receiver. At this time, the opening face of the loop antenna 3 is
in a direction almost perpendicular to the surface of a living body
for improving sensitivity.
Inventors: |
Matsumura, Fumiyuki; (Tokyo,
JP) ; Sekiguchi, Tetsushi; (Tokyo, JP) ;
Sakata, Hiroshi; (Tokyo, JP) ; Hosaka, Hidehiro;
(Tokyo, JP) |
Correspondence
Address: |
SUGHRUE MION, PLLC
2100 Pennsylvania Avenue, NW
Washington
DC
20037-3213
US
|
Assignee: |
NIHON KOHDEN CORPORATION
|
Family ID: |
26580800 |
Appl. No.: |
10/098400 |
Filed: |
March 18, 2002 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10098400 |
Mar 18, 2002 |
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09657630 |
Sep 8, 2000 |
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6389309 |
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09657630 |
Sep 8, 2000 |
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09220751 |
Dec 28, 1998 |
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6161036 |
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Current U.S.
Class: |
600/509 |
Current CPC
Class: |
A61B 5/282 20210101;
Y10S 128/903 20130101; A61B 2560/045 20130101; A61B 5/0008
20130101; A61B 2560/0475 20130101; A61B 2560/0412 20130101; A61B
5/0006 20130101; A61B 5/332 20210101; A61B 5/335 20210101 |
Class at
Publication: |
600/509 |
International
Class: |
A61B 005/04 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 25, 1997 |
JP |
P. HEI. 9-358536 |
Dec 26, 1997 |
JP |
P. HEI. 9-359933 |
Claims
What is claimed is:
1. A biological signal transmission apparatus comprising: at least
one electrode for detecting a biological signal; a support for
supporting said electrode, said support being placed on a living
body surface; a transmitter having electric circuitry for
processing the biological signal detected on said electrode; and
two loop antennas for emitting the biological signal processed by
the electric circuitry to a receiver, said loop antennas being
disposed in such a manner that opening faces are placed in a
direction almost perpendicular to the living body surface and are
almost at right angles to each other.
2. The biological signal transmission apparatus as claimed in claim
1 wherein at least one of said loop antennas is contained in said
transmitter.
3. The biological signal transmission apparatus as claimed in claim
1 wherein at least one of said at least one loop antennas is
divided into two parts, wherein one loop antenna division part is
disposed in said support and the other is disposed in said
transmitter, such that when said transmitter is attached to said
support, the loop antenna division parts are connected into one
piece.
4. The biological signal transmission apparatus as claimed in claim
1 wherein said support and said transmitter have connection members
for connecting to each other and, wherein said loop antennas are
integral with said support and connected to an output of the
electric circuitry through said connection members when said
transmitter is placed on said support.
5. A biological signal transmission apparatus comprising: at least
one electrode for detecting a biological signal; a support for
supporting said electrode, said support being placed on a living
body surface; a transmitter having electric circuitry for
processing the biological signal detected on said electrode; at
least one loop antenna for emitting the biological signal processed
by the electric circuitry to a receiver, said loop antenna being
disposed so that an opening face is placed in a direction almost
perpendicular to the living body surface; and a microstrip antenna
having a radiation plate and a base plate opposed in parallel with
the living body surface, the base plate being placed nearer to the
living body surface.
6. A biological signal transmission apparatus comprising: at least
one electrode for detecting a biological signal; a support for
supporting said electrode, said support being placed on a living
body surface; a transmitter having electric circuitry for
processing the biological signal detected on said electrode; two
loop antennas for emitting the biological signal processed by the
electric circuitry to a receiver, said loop antennas being disposed
so that opening faces are placed in a direction almost
perpendicular to the living body surface and are almost at right
angles to each other; and a microstrip antenna having a radiation
plate and a base plate opposed in parallel with the living body
surface, the base plate being placed nearer to the living body
surface.
7. The biological signal transmission apparatus as claimed in claim
5 wherein at least one of said loop antennas and said microstrip
antenna is contained in said transmitter.
8. The biological signal transmission apparatus as claimed in claim
5 wherein at least one of said loop antennas and said microstrip
antenna is integral with said support and said loop antenna or said
microstrip antenna is connected to output of the electric circuitry
through a connection member and wherein said transmitter is placed
on said support.
9. A biological signal transmission apparatus comprising: at least
one electrode for detecting a biological signal; a support for
supporting said electrode, said support being placed on a living
body surface; a transmitter having electric circuitry for
processing the biological signal detected on said electrode; and a
microstrip antenna having a radiation plate and a base plate
opposed in parallel with the living body surface, the base plate
being placed nearer to the living body surface.
10. The biological signal transmission apparatus as claimed in
claim 9 wherein said microstrip antenna is contained in said
transmitter.
11. The biological signal transmission apparatus as claimed in
claim 9 wherein said microstrip antenna is integral with said
support and is connected to output of the electric circuitry
through a connection member and wherein said transmitter is placed
on said support.
12. The biological signal transmission apparatus as claimed in
claim 8, wherein at least one of said two loop antennas and said
microstrip antenna is contained in said transmitter.
13. The biological signal transmission apparatus as claimed in
claim 8, wherein at least one of said two loop antennas and said
microstrip antenna is integral with said support and wherein one of
either said loop antenna and said microstrip antenna integral with
said support is connected to an output of the electric circuitry
through a connection member and wherein said transmitter is placed
on said support.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] This invention relates to a biological signal transmission
apparatus of a medical telemeter for transmitting a biological
signal from a transmitter through an antenna to a receiver and in
particular to a biological signal transmission apparatus using a
loop antenna, a microstrip antenna as an antenna.
[0003] 2. Related Art
[0004] A system for transmitting by radio a biological signal
detected on an electrode placed on a subject to a nearby computer
diagnostic apparatus, etc., via an antenna for diagnosis is known.
Hitherto, various propositions have been made as a transmission
apparatus used with such a system.
[0005] In a proposition described in JP-A-60-97103U, two electrodes
502 and 503 attached to a chest belt 501 and a transmitter main
unit 504 placed on a wrist of a subject are connected by electrode
leads 505 and 506, as shown in FIG. 34. An antenna line 507 from
the transmitter main unit 504 is placed closely on the leads 505
and 506 in parallel therewith and an end of the antenna line 507 is
buried in the chest belt 501. The electrode leads 505 and 506 and
the antenna line 507 are insulated from each other and the end of
the antenna line 507 is also electrically insulated so as not to
touch the body surface of the subject.
[0006] According to the proposition, the antenna line 507 is placed
closely on the leads 505 and 506 and thus can be made 1 m or longer
without disturbing any motion, and the efficiency of the
transmitter 504 can be improved and miniaturized for enhancing
portability of the transmitter.
[0007] In a proposition described in JP-A-62-202804U, a pair of
electrodes 201 and 202 is placed in unit cases 203 and 204, which
are opened at bottoms for exposing the electrodes 201 and 202, and
both ends of an antenna line 205 are connected to the electrodes
201 and 202, as shown in FIG. 35. The unit cases 203 and 204 are
coupled by a connection cable 206 and the antenna line 205 is
inserted into the connection cable 206.
[0008] According to the proposition, the electrodes 201 and 202
placed in a pair of unit cases 203 and 204 are fitted to a heart
rate detection part of a living body and a signal from the antenna
line 205 is transmitted, so that the device is easily attached and
detached and moreover can be placed without an oppressive feeling
or a feeling of wrongness on the chest of the subject.
[0009] In a proposition described in JP-A-63-32501U, a device
comprises a pair of electrodes 301 and 302, a transmitter main unit
303 having electric circuitry for processing an
electrocardiographic signal detected on the electrodes 301 and 302,
and an antenna 304 for sending the resultant signal to a receiver
by a radio wave, as shown in FIG. 36. The antenna 304 is covered
with water-repellent fibers and is put on the surface of a human
body.
[0010] According to the proposition, the antenna 304 is covered
with water-repellent fibers and is connected to the transmitter
main unit 303 so that it is put on the surface of a human body.
Thus, when the device is attached to a subject, clothes of the
subject do not swell locally and moreover it is not feared that the
electrode 301, 302 maybe off the attachment point. Resultantly,
sufficiently strong radio waves can be sent to the receiver in
addition to ease of use.
[0011] In a proposition described in JP-A-9-108194, a base sheet
401 placed on the anterior chest wall of a subject is formed like
an L letter, a longwise portion 401a is put along the breast bone
line of the subject, and a widthwise portion 401c is directed
toward the heart side from a corner 401b positioned near the
xiphisternum of the subject, as shown in FIG. 37. The base sheet
401 is formed on a rear with an adhesion layer made to adhere to
the anterior chest wall. A first electrode 402 is attached in the
proximity of the corner 401b, a second electrode 403 is attached in
the proximity of the upper end part of the longwise portion 401a,
and a third electrode 404 is attached in the proximity of a side
end part of the widthwise portion 401c. Further, a fourth electrode
405 is attached slantingly below the second electrode 403 and a
fifth electrode 406 is attached above the third electrode 404.
[0012] Of the five electrodes arranged as described above, .alpha.
induction is detected between the electrodes 402 and 403 and .beta.
induction is detected between the electrodes 403 and 404. .gamma.
induction for ischaemia of side and front and rear walls in a
high-potential direction week in sensitivity only with a induction
and .beta. induction is detected by means of the electrodes 405 and
406. The electrocardiographic signals induced to the electrodes are
amplified and modulated by a circuit unit 407 attached to the base
sheet 401 and are transmitted to the receiver through an antenna
408 attached along the longwise portion 401a.
[0013] According to the proposition, the electrodes 402 to 406, the
circuit unit 407, and the antenna 408 are mounted integrally on the
base sheet 401, so that the device is easily placed on the subject
and action is not limited.
[0014] In the examples in the related arts described above, the
antennas are monopole antennas using the electricity length of a
quarter the wave length. For example, assuming that the
transmission frequency is 300 MHz, the wave length is 1 m and the
antenna length becomes 25 cm. To place the monopole antenna so that
it is not affected by a human body as much as possible, the
monopole antenna may be placed in a direction perpendicular to the
surface of a human body and distant from the human body. However,
the antenna length is long (in this case, 25 cm), thus when the
transmitter is placed on a human body, it disturbs the motion of
the human body. If the transmitter is placed along the surface of
the human body so as to facilitate the motion, radio waves radiated
from the antenna are affected by the human body as described above,
thus the gain is easily degraded. Also, although employing small
and compact transmitter and electrode, there is still a problem
that long using for standard limb lead (II) between electrodes
disturb patient.
SUMMARY OF THE INVENTION
[0015] It is therefore an object of the invention to provide a
small-sized biological signal transmission apparatus that can emit
a biological signal detected on an electrode placed on the surface
of a living body to a receiver with stable and good sensitivity and
can be easily placed on the living body.
[0016] According to an aspect of the present invention, there is
provided a biological signal transmission apparatus comprising an
electrode for detecting a biological signal, a support for
supporting the electrode, the support being placed on a living body
surface, a transmitter having electric circuitry for processing the
biological signal detected on the electrode, and at least one loop
antenna for emitting the biological signal processed by the
electric circuitry to a receiver, the loop antenna being disposed
so that an opening face is placed in a direction almost
perpendicular to the living body surface.
[0017] According to another aspect of the present invention, there
is provided a biological signal transmission apparatus comprising
an electrode for detecting a biological signal, a support for
supporting the electrode, the support being placed on a living body
surface, a transmitter having electric circuitry for processing the
biological signal detected on the electrode, and two loop antennas
for emitting the biological signal processed by the electric
circuitry to a receiver, the loop antennas being disposed so that
opening faces are placed in a direction almost perpendicular to the
living body surface and are almost at right angles to each
other.
[0018] According to another aspect of the present invention, in the
biological signal transmission apparatus, at least one of the loop
antennas is contained in the transmitter.
[0019] According to another aspect of the present invention, in the
biological signal transmission apparatus, at least one of the loop
antennas is divided into two parts, one loop antenna division part
is placed in the support and the other is placed in the
transmitter, and the transmitter is placed on the support, thereby
putting the loop antenna division parts into one piece.
[0020] According to another aspect of the present invention, in the
biological signal transmission apparatus, the loop antenna is
integral with the support and is connected at both ends to output
of the electric circuitry through connection members and the
transmitter is placed on the support.
[0021] According to another aspect of the present invention, there
is provided a biological signal transmission apparatus comprising
an electrode for detecting a biological signal, a support for
supporting the electrode, the support being placed on a living body
surface, a transmitter having electric circuitry for processing the
biological signal detected on the electrode, at least one loop
antenna for emitting the biological signal processed by the
electric circuitry to a receiver, the loop antenna being disposed
so that an opening face is placed in a direction almost
perpendicular to the living body surface, and a microstrip antenna
having a radiation plate and a base plate opposed in parallel with
the living body surface, the base plate being placed nearer to the
living body surface.
[0022] According to another aspect of the present invention, there
is provided a biological signal transmission apparatus comprising
an electrode for detecting a biological signal, a support for
supporting the electrode, the support being placed on a living body
surface, a transmitter having electric circuitry for processing the
biological signal detected on the electrode, two loop antennas for
emitting the biological signal processed by the electric circuitry
to a receiver, the loop antennas being disposed so that opening
faces are placed in a direction almost perpendicular to the living
body surface and are almost at right angles to each other, and a
microstrip antenna having a radiation plate and a base plate
opposed in parallel with the living body surface, the base plate
being placed nearer to the living body surface.
[0023] In the biological signal transmission apparatus of the
present invention, at least one of the loop antennas and the
microstrip antenna is contained in the transmitter.
[0024] In the biological signal transmission apparatus of the
present invention, at least one of the loop antennas and the
microstrip antenna is integral with the support and the loop
antenna or the microstrip antenna is connected to output of the
electric circuitry through a connection member and the transmitter
is placed on the support.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] In the accompanying drawings:
[0026] FIG. 1 is a block diagram to show a configuration example of
a first embodiment of a biological signal transmission apparatus of
the invention;
[0027] FIG. 2 is a longitudinal sectional view to show the
configuration of a living body placement section in FIG. 1;
[0028] FIG. 3 is an exploded perspective view of the living body
placement section shown in FIG. 2;
[0029] FIG. 4 is an external perspective view of the living body
placement section and a transmitter in FIG. 1;
[0030] FIG. 5 is a plan view to show the form of a modified example
of a support in FIG. 3;
[0031] FIG. 6 is a perspective view to show the structure of a loop
antenna in FIG. 3;
[0032] FIG. 7 is a perspective view to show the structure of a
modified example of the loop antenna in FIG. 3;
[0033] FIG. 8 is an exploded longitudinal sectional view to show
the attachment structure of an electrode in FIG. 2 and FIG. 3;
[0034] FIG. 9 is a block diagram to show a configuration example of
a second embodiment of the invention;
[0035] FIG. 10 is an exploded perspective view to show a
configuration example of a living body placement section and a
transmitter in FIG. 9;
[0036] FIG. 11 is an external perspective view of the living body
placement section and the transmitter in FIG. 9;
[0037] FIG. 12 is a block diagram of a living body placement
section to show a configuration wherein electrodes in FIG. 9 are
replaced with a transducer;
[0038] FIG. 13 is a longitudinal sectional view to show a
configuration example of a third embodiment of the invention;
[0039] FIG. 14 is a block diagram to show the configuration of a
fourth embodiment of a biological signal transmission apparatus of
the invention;
[0040] FIG. 15 is an exploded perspective view to show a
configuration example of a living body placement section in FIG.
14;
[0041] FIG. 16 is an external perspective view of the living body
placement section shown in FIG. 15 and a transmitter placed
thereon;
[0042] FIG. 17 is a plan view to show the form of a modified
example of a support in FIG. 15;
[0043] FIG. 18 is an exploded longitudinal sectional view to show
the attachment structure of an electrode in FIG. 17;
[0044] FIG. 19 is an external perspective view to show another
configuration example of the living body placement section in FIG.
14;
[0045] FIG. 20 is an external perspective view of the living body
placement section shown in FIG. 19 and a transmitter placed
thereon;
[0046] FIG. 21 is a block diagram to show a configuration example
of a fifth embodiment of the invention;
[0047] FIG. 22 is an exploded perspective view to show a
configuration example of a living body placement section in FIG.
21;
[0048] FIG. 23 is an external perspective view of the living body
placement section shown in FIG. 22 and a transmitter placed
thereon;
[0049] FIG. 24 is a schematic representation to show placement of
antennas when the transmitter in FIG. 23 is placed on the living
body placement section;
[0050] FIG. 25 is a block diagram to show a configuration example
of a sixth embodiment of the invention;
[0051] FIG. 26 is an exploded perspective view to show a
configuration example of a living body placement section in FIG.
25;
[0052] FIG. 27 is an external perspective view of the living body
placement section shown in FIG. 26 and a transmitter placed
thereon;
[0053] FIG. 28 is a block diagram to show a configuration example
of a seventh embodiment of the invention;
[0054] FIG. 29 is an exploded perspective view to show a
configuration example of a living body placement section and a
transmitter in FIG. 28;
[0055] FIG. 30 is an illustration to show an example of placing the
biological signal transmission apparatus of the invention on a
living body;
[0056] FIG. 31 (a) is a plan view of an illustration to compare a
loop antenna and a monopole antenna placed on a human body in
directivity and FIG. 31 (b) is side view of the arrangement of the
loop antenna and the monopole antenna attached with the human body
along with FIG. 31 (a);
[0057] FIG. 32 (a) is a plan view of an illustration to show the
directivity of one loop antenna placed on a human body, and FIG. 32
(b) is side view of the arrangement of one loop antenna attached
with the human body along with FIG. 32 (a);
[0058] FIG. 33 (a) is a plan view of an illustration to show the
directivity of two loop antennas placed on a human body, and FIG.
33 (b) is side view of the arrangement of two loop antennas
attached with the human body along with FIG. 33 (a);
[0059] FIG. 34 is a front view to show the configuration of a first
example of a biological signal transmission apparatus in a related
art;
[0060] FIG. 35 is a plan view to show the configuration of a second
example of a biological signal transmission apparatus in a related
art;
[0061] FIG. 36 is a front view to show the configuration of a third
example of a biological signal transmission apparatus in a related
art;
[0062] FIG. 37 is a plan view to show the configuration of a fourth
example of a biological signal transmission apparatus in a related
art;
[0063] FIG. 38 is a front view of the water-containing gels
positioned through midclavicular line and parallel to a clavicle;
and
[0064] FIG. 39 is a front view of the water-containing gels
attached on a chest defiend between a xiphoid process and a navel
through and perpendicular to a midsternal line.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0065] Referring now to the accompanying drawings, there are shown
preferred embodiments of a biological signal transmission apparatus
of the invention. FIG. 1 is a block diagram to show a configuration
example of a first embodiment of the invention. FIG. 2 is a
longitudinal sectional view to show the configuration of a living
body placement section in FIG. 1. FIG. 3 is an exploded perspective
view of the living body placement section shown in FIG. 2. FIG. 4
is an external perspective view of the living body placement
section and a transmitter in FIG. 1.
[0066] In FIG. 1, a living body placement section 1 comprises a
loop antenna 3 and an electrode 4 integrally mounted on a flat
support 2 formed of an insulating material. A transmitter 5
comprises electric circuitry 10 made up of an amplification section
6, a modulation section 7, a power supply section 8, and a
transmission section 9. The electrode 4 and the amplification
section 6 and the loop antenna 3 and the transmission section 9 are
electrically connected through connectors 11, 12, and 13. Numeral
14 is an electrode placed on another part of a living body. The
electrode 14 is connected to the amplification section 6 by a
connector 15.
[0067] Power is supplied from the power supply section 8 to the
amplification section 6, the modulation section 7, and the
transmission section 9. When the support 2 is placed on the living
body surface of a subject, a biological signal detected on the
electrode 4 is amplified by the amplification section 6 and is
modulated by the modulation section 7, then is sent from the
transmission section 9 to the loop antenna 3. The biological signal
is transmitted by radio from the loop antenna 3 to a receiver (not
shown).
[0068] In FIG. 2 and FIG. 3, the support 2 is formed of an
insulating material like a square plate. The loop antenna 3 formed
of a conductive material like a belt is placed along one side of
the lower face of the support 2 and the loop antenna 3 is folded at
both ends back to the upper face of the support 2 so as to sandwich
the support 2. Convex hooks 16 and 17 forming a connector are fixed
at both ends of the loop antenna 3.
[0069] The electrode 4 passes through the support 2 from the lower
face thereof, projects upward, and is fixedly secured in the
portion of the support 2 where the loop antenna 3 is not placed.
Conductive water-containing gel 18 is applied to the lower end face
of the electrode 4. A hook 19 is attached to one end of the
electrode 4 passing through the support 2 from the lower face
thereof and projecting upward. An insulating sheet 20 covering the
loop antenna 3 is bonded to the full lower face of the support 2
and the electrode 4 is exposed to the lower face through a hole 20a
made in the insulating sheet 20. An adhesive 21 is applied to the
lower face of the insulating sheet 20. The upper face of the
support 2 is also covered with an insulating sheet 22 and the hooks
16, 17, and 19 pass through the insulating sheet 22 and project
upward.
[0070] The transmitter 5 is placed on and fixed to the described
living body placement section 1, as shown in FIG. 4. At this time,
the hooks 16, 17, and 19 are connected to the corresponding
connectors (not shown) of the transmission section 9 and the
amplification section 6 in the transmitter 5. As shown in FIG. 30,
when the living body placement section 1 is bonded to the surface
of the living body of a subject via the adhesive 21, a biological
signal detected on the electrode 4 is sent through the hook 19 to
the transmitter 5 and is processed by the electric circuitry 10 in
the transmitter 5, then is sent through the hooks 16 and 17 to the
loop antenna 3 from which the biological signal is transmitted to
the receiver (not shown) by radio.
First Embodiment
[0071] Next, specific structures and materials of the parts of the
first embodiment shown in FIG. 1 to FIG. 4 will be discussed in
detail. The support 2 is several ten .mu.m to several mm thick, for
example, and has reasonable rigidity for holding the living body
placement section 1. In the above-described example, the support 2
is shaped like a square plate, but may be of any shape like a
center-constricted plate, for example, as shown in FIG. 5. For
example, the support 2 is formed of a material of paper or a
macromolecular dielectric substance, such as vinyl chloride,
polyurethane, polystyrene, polycarbonate, polypropylene,
fluororesin, silicone resin, cellulose acetate, polyester, rayon,
nylon, vinylon, epoxy resin, or ceramics.
[0072] The loop antenna 3 is several .mu.m to several mm thick, for
example, has a surrounding length of about a several'th to a
several tenth the wave length, and is formed of an elongated
conductive film. The planar shape is not limited; for example, the
loop antenna 3 may be narrow as shown in FIG. 6 or may be wide as
shown in FIG. 7. For example, metal, carbon, a macromolecular
conductive substance, or resin to which conductive plating is given
is used as the material of the loop antenna 3.
[0073] The electrode 4 is fixed to the support 2 through the
connector 11, is a conductive substance itself, and acts as an
electrode for deriving a living body electricity phenomenon. It may
be of any structure if it can be stably fixed to the hook 19 as the
connector, for example, as shown in FIG. 8. The material of the
electrode 4 may be a conductive substance similar to connector
described later, and is not limited. For example, a macromolecular
conductive substance, such as conductive rubber or water-containing
resin, metal, such as copper, stainless steel, or aluminum, carbon,
such as carbon fibers or graphite, resin to which conductive
plating is given (for example, a conductive metal film of gold,
silver, copper, nickel, aluminum, palladium, platinum, etc., is
formed on the surface of a macromolecular insulating substance or a
macromolecular conductive substance by means of sputtering
evaporation, electrolytic plating, electroless plating, etc.,) is
used as the material of the electrode 4.
[0074] The water-containing gel 18 makes electric conduction
between the electrode 4 and a living body surface and preferably it
has adhesion to a living body. For example, gelatin, polyacrylic
acid, its salt, karaya gum, any other water-soluble or
water-dispersable acrylic-family polymer, water-soluble or
water-dispersable polymer of polyacrylamide, polyvinyl alcohol,
carboxymethyl cellulose, polyurethane, etc., or the like can be
named as the base material for forming the gel layer.
[0075] In the above-described example, the hooks 16, 17, and 19 are
used as the parts forming the connectors 11, 12, and 13, but the
scope of the invention is not limited to them. For example, a
structure of a general-purpose electric connector, a contact-type
connector, etc., may be used. A material similar to that of the
electrode 4 described above can be used.
[0076] The insulating sheets 20 and 22 are provided so that a human
body and the loop antenna 3 do not come in direct contact with each
other. They may be made of any material if the material has an
insulating property; the material is not limited.
[0077] The adhesive 21 is provided for strongly fixing the living
body placement section 1 to a living body; preferably it is a
substance not giving an impetus to the living body. For example, a
known adhesive material excellent in intimate contact with the
living body placement section 1, such as double-sided adhesive
tape, an acrylic family, a rubber family, or a vinyl ether family,
can be used.
[0078] According to the embodiment, the loop antenna 3 is placed
near the surface of a living body through the support 2 and
moreover the opening face of the loop antenna 3 is almost at right
angles to the living body surface, so that the sensitivity can be
improved and the gain can be increased because of the known loop
antenna characteristics.
Second Embodiment
[0079] FIG. 9 to FIG. 11 show a configuration example of a second
embodiment of the invention. Parts identical with or similar to
those previously described with reference to FIG. 1 to FIG. 4 are
denoted by the same reference numerals in FIG. 9 to FIG. 11 and
will not be discussed again in detail.
[0080] In the second embodiment, the number of electrodes 4 is two
and biological signals detected on electrodes 4a and 4b are sent
through connectors 11a and 11b to an amplification section 6, as
shown in FIG. 9. Other components and functions are almost similar
to those of the first embodiment previously described with
reference to FIG. 1 to FIG. 4.
[0081] FIG. 10 is an exploded perspective view to show a
configuration example of a living body placement section 1 and a
transmitter 5 in FIG. 9. FIG. 11 is an external perspective view of
the living body placement section 1 and the transmitter 5 in FIG.
9. In FIG. 10, ends of conductive terminals 18c and 18d disposed on
the lower face of a support 2 are electrically connected to
caulking devices 31a and 31b respectively, and conductive
water-containing gels 18a and 18b are attached to opposite ends of
the conductive terminals 18c and 18d. The caulking devices 31a and
31b pass through the support 2 and project upward and are fixed to
the support 2 together with the conductive terminals 18c and
18d.
[0082] A loop antenna 3 is placed on the lower face of the support
2 between the conductive terminals 18c and 18d and is folded at
both ends back to the upper face of the support 2 so as to sandwich
the support 2. An insulating sheet 20 for covering the loop antenna
3, the caulking devices 31a and 31b, and the conductive terminals
18c and 18d is bonded to the space between the conductive
water-containing gels 18a and 18b on the lower face of the support
2, and an adhesive 21 is applied to the lower face of the
insulating sheet 20.
[0083] The upper face of the support 2 is also covered with an
insulating sheet 22. Convex hooks 19a and 19b placed at the upper
ends of the caulking devices 31a and 31b and convex hooks 16 and 17
fixed to both ends of the loop antenna 3 pass through the
insulating sheet 22 and project upward. A transmitter 5 is made up
of an upper lid 40a and a lower lid 40b making up a cabinet 40, a
board 41 housed therein, and electric circuitry 10 mounted on the
board 41. The board 41 is formed on a surface with four lands 42
connected to the electric circuitry 10. It is fixed to the lower
lid 40b through the lands 42 by a caulking device 43 and a concave
hook 44. Also in the embodiment, as shown in FIG. 11, the
transmitter 5 is placed on and fixed to a living body placement
section 1 through the convex hooks 16, 17, 19a, and 19b and the
concave hook 44, and the functions and advantages similar to those
of the first embodiment previously described with reference to FIG.
1 to FIG. 4 can be provided. The structures and materials of the
members shown in FIG. 9 to FIG. 11 are almost similar to those of
the first embodiment previously described with reference to FIG. 1
to FIG. 4.
[0084] In the second embodiment, the number of the electrodes 4 is
two, but three or more electrodes 4 may be used. In this case, the
electrodes 4 are placed at appropriate positions of the living body
placement section 1 and are related to the connectors 11 and the
amplification section 6 and a modulation section 7 in the electric
circuitry 10, whereby a large number of biological signals can be
derived and amplified, then transmitted from a transmission section
9, needless to say.
[0085] As shown in FIG. 12, the electrodes 4 are replaced with a
transducer 23, whereby the temperature, blood pressure, etc., of a
living body can also be detected.
Third Embodiment
[0086] FIG. 13 is a longitudinal sectional view to show a
configuration example of a third embodiment of the invention. Parts
identical with or similar to those previously described with
reference to FIG. 1 to FIG. 4 are denoted by the same reference
numerals in FIG. 13 and will not be discussed again in detail. The
third embodiment is characterized by the fact that a part of a loop
antenna 3 is formed according to a thin film technology of silk
print, etc. As shown in FIG. 13, through holes are made near two
opposed sides of a support 2 and are filled with conductive
material 24. The support 2 is formed on both faces with conductive
thin films 25 according to the thin film technology and the upper
conductive thin film 25 is divided into two portions. The upper and
lower conductive thin films 25 are electrically connected at both
ends to the conductive material 24 with which the through holes are
filled, forming the loop antenna 3.
[0087] The upper and lower faces of the support 2 are covered with
insulating sheets 20 and 22 for covering the conductive thin films
25 and the upper insulating sheet 22 is cut at the center for
exposing the conductive thin film 25 at both ends thereof. When a
transmitter 5 is placed on a living body placement section 1, a
pair of conductive contact connectors 26 projecting from the lower
face of the transmitter 5 abuts the exposure parts of the
conductive thin film 25 at both ends thereof for introducing a
signal transmitted from the transmitter 5 into the loop antenna
formed of the conductive thin films 25. A hook 19 fixed to an
electrode 4 is coupled to a connector 11 like a concave hook to the
transmitter 5, as in the first embodiment.
[0088] According to the third embodiment, the manufacturing process
is simplified and costs can be reduced as compared with the case
where the loop antenna 3 is formed as a thin-film separate body and
is folded at both ends back to the support 2 and fixed as in the
configuration examples of the first and second embodiments.
[0089] In FIG. 13, one electrode 4 is shown, but the third
embodiment can also be applied to the case where the number of the
electrodes 4 is two or more as in the configuration example of the
second embodiment shown in FIG. 9 and FIG. 10 and the case where
the electrode 4 is the transducer 23 as shown in FIG. 12; similar
advantages can be provided.
Fourth Embodiment
[0090] FIG. 14 is a block diagram to show a configuration example
of a fourth embodiment of the invention. FIG. 15 is an exploded
perspective view to show a specific configuration example of a
living body placement section in FIG. 14. FIG. 16 is an external
perspective view of the living body placement section shown in FIG.
14 and a transmitter placed thereon. FIG. 17 is a plan view to show
the form of a modified example of a support in FIG. 15. FIG. 18 is
a drawing to show the attachment structure of an electrode in FIG.
17.
[0091] In FIG. 14, a living body placement section 101 comprises
division parts 103a and 104a of two antennas 103 and 104 each
divided into two parts and two electrodes 105a and 105b mounted on
a flat support 102 formed of an insulating material. In the
embodiment, the antenna 103 is a loop antenna and the antenna 104
is a microstrip antenna (MSA). A transmitter 106 comprises electric
circuitry 111 made up of an amplification section 107, a modulation
section 108, a power supply section 109, and a transmission section
110 and other division parts 103b and 104b of the two antennas 103
and 104. The electrodes 105a and 105b and the amplification section
107 are connected through connectors 112a and 112b, one end of the
part 103a of the antenna 103 and one end of the part 103b of the
antenna 103 are connected through a connector 113a, and the
opposite end of the part 103a of the antenna 103 and the
transmission section 110 are connected through a connector 113b.
The opposite end of the part 103b of the antenna 103 is connected
to the transmission section 110. The part 104a of the antenna 104
(MSA) is a base plate and the part 104b of the antenna 104 is a
radiation plate. The base plate 104a is connected to the
transmission section 110 through a connector 114 and the radiation
plate 104b is directly connected to the transmission section
110.
[0092] Power is supplied from the power supply section 109 to the
amplification section 107, the modulation section 108, and the
transmission section 110. When the support 102 is placed on the
living body surface of a subject, biological signals detected on
the electrodes 105a and 105b are amplified by the amplification
section 107 and are modulated by the modulation section 108, then
are sent from the transmission section 110 to the antennas 103 and
104. The biological signals are transmitted by radio from the
antennas 103 and 104 to a receiver (not shown).
[0093] In FIG. 15 and FIG. 16, the support 102 is formed of a
dielectric material like a rectangular plate. The loop antenna 103
formed of a conductive material like a belt is divided into two
parts. One loop antenna part 103a is placed on one side of the
lower face of the support 102 and caulking devices 115a and 115b
are inserted into both ends of the loop antenna part 103a. The
caulking devices 115a and 115b pass through the loop antenna part
103a from the lower face thereof and further pass through the
support 102 and project upward. Hooks 116a and 116b are fixed to
the projection ends of the caulking devices 115a and 115b by
caulking. The loop antenna part 103b is connected at one end to the
hook 116a. The hook 116b is connected to the transmission section
110.
[0094] As described above, the MSA 104 consists of the base plate
104a and the radiation plate 104b, which are opposed to each other
in parallel. As shown in FIG. 15, the base plate 104a is fixed
almost at the center of the lower face of the support 102 and is
formed with a projection 141a at the center of one side opposite to
the loop antenna part 103a. A caulking device 117 is inserted into
the projection 141a; it passes through the base plate 114a from the
lower face thereof and further passes through the support 102 and
projects upward. A hook 118 for the base plate is fixed to the
projection ends of the caulking device 117 by caulking.
[0095] A pair of plate-like conductive terminals 121c and 121d is
placed at both sides of the projection 141a of the base plate 104a
in parallel with one side of the base plate 104a and are fixed to
the lower face of the support 102. Caulking devices 119a and 119b
are inserted into opposed ends of the conductive terminals 121c and
121d; they pass through the conductive terminals 121c and 121d from
the lower faces thereof and further pass through the support 102
and project upward. Hooks 120a and 120b for deriving
electrocardiographic signals are fixed to the projection ends of
the caulking devices 119a and 119b by caulking. Conductive
water-containing gels 121a and 121b are attached to outer ends of
the conductive terminals 121c and 121d. Further, the lower faces of
the loop antenna part 103a, the base plate 104a, and the conductive
terminals 121c and 121d are covered with an insulating sheet 122
and an adhesive 123 is applied to the lower face of the insulating
sheet 122.
[0096] The transmitter 106 is shaped like a square can as shown in
FIG. 16 and contains a board (not shown) on which the electric
circuitry 111 is mounted. On the board, the loop antenna part 103b
and the radiation plate 104b are placed at the positions
corresponding to the loop antenna part 103a and the base plate 104a
in the living body placement section 101, as shown in FIG. 15. When
the transmitter 106 is attached to the living body placement
section 101, the hook 116a projecting from the top of the support
102 of the living body placement section 101 is fitted to one end
of the loop antenna part 103b and the convex hooks 118, 120a, and
120b are connected to concave hooks 124, 125a, and 125b formed at
predetermined positions of the board. The concave hooks 124, 125a,
and 125b are connected to the electric circuitry 111. Further, the
opposite end of the loop antenna part 103b is also connected to the
electric circuitry 111.
[0097] Next, specific structures and materials of the parts of the
fourth embodiment shown in FIG. 14 to FIG. 18 will be discussed in
detail. The support 102 is formed of a dielectric substance which
is several ten .mu.m to several mm thick, for example, and has
reasonable rigidity and dielectric constant for holding the living
body placement section 101. In the above-described example, the
support 102 is shaped like a rectangular plate, but may be of any
shape like a hand drum, for example, as shown in FIG. 17. The
support 102 may be formed of a material of a dielectric substance
having a dielectric constant fitted to the use frequency and the
shapes of the base plate 104a and the radiation plate 104b, for
example, paper or a macromolecular dielectric substance, such as
vinyl chloride, polyurethane, polystyrene, polycarbonate,
polypropylene, fluoroplastics, silicone resin, cellulose acetate,
polyester, rayon, nylon, vinylon, epoxy resin, or ceramics.
[0098] The loop antenna 103 is several .mu.m to several mm thick,
for example, has a surrounding length of about a several'th to a
several tenth the wave length, and is formed of an elongated
conductive film. The planar shape is not limited. For example,
metal, carbon, a macromolecular conductive substance, or resin to
which conductive plating is given is used as the material of the
loop antenna 103.
[0099] The base plate 104a basically has a large area in the
allowable range and a structure for making a signal emitted from
the radiation plate 104b hard to be affected by a human body, etc.
For example, metal, carbon, a macromolecular conductive substance,
or resin to which conductive plating is given is used as the
material of the base plate 104a. The shape of the base plate 104a
also changes corresponding to the antenna characteristics.
[0100] The radiation plate 104b is formed of a conductive film
which is several .mu.m to several mm thick, for example, and has an
area determined by frequency. In the above-described example, the
radiation plate 104b is shaped like a rectangular plate, but may be
of any shape. For example, metal, carbon, a macromolecular
conductive substance, or resin to which conductive plating is given
is used as the material of the radiation plate 104b like the base
plate 104a.
[0101] The caulking devices 115a, 115b, 117, 119a, and 119b and the
conductive terminals 121c and 121d are fixed to the support 102
through the hooks 116a, 116b, 118, 120a, and 120b, are conductive
substances themselves, and act as electrodes for deriving a living
body electricity phenomenon and electrodes for transferring signals
to the base plate 104a. They may be of any structure if it can be
stably fixed to the hook 120 as the connector, for example, as
shown in FIG. 18. The material may be a conductive substance and is
not limited. For example, a macromolecular conductive substance,
such as conductive rubber or water-containing resin, metal, such as
copper, stainless steel, or aluminum, carbon, such as carbon fibers
or graphite, resin to which conductive plating is given (for
example, a conductive metal film of gold, silver, copper, nickel,
aluminum, palladium, platinum, etc., is formed on the surface of a
macromolecular insulating substance or a macromolecular conductive
substance by means of sputtering evaporation, electrolytic plating,
electroless plating, etc.,) is used as the material.
[0102] In the above-described example, the hooks 116a, 116b, 118,
120a, and 120b are used as the parts forming the connectors 112c,
112d, 113c, 113d, and 114, but the scope of the invention is not
limited to them. For example, a structure of a general-purpose
electric connector, a contact-type connector, etc., may be used. A
material similar to that of the caulking devices 115a, 115b, 117,
119a and 119b described above can be used.
[0103] The water-containing gel 121a, 121b makes electric
conduction between the conductive terminal 121c, 121d and a living
body surface and preferably it has adhesion to a living body. For
example, gelatin, polyacrylic acid, its salt, karaya gum, any other
water-soluble or water-dispersable acrylic-family polymer,
polyacrylic-family polymer, water-soluble or water-dispersable
polymer of polyacrylamide, polyvinyl alcohol, carboxymethyl
cellulose, polyurethane, etc., or the like can be named as the base
material for forming the gel layer. The length and breadth of the
water-containing gels 121a, 121b to be attached to living body is
the range from approximately 2 to 6 cm. But the shape of the
water-containing gels are not limited as described shape, and any
figure like a square, rectangle, circle, oval are applicapable.
[0104] Preferably, the distance between nearest of water-containing
gels 121a, 121b is the range from approximately 1.0 to 7.5 cm to
detect heat rate information and etc. And more specifically, it's
preferable to make the distance approximately 2.0 to 7.5 cm to
detect a small amplitude P wave of ECG sufficiently.
[0105] The insulating sheet 122 is provided so that a human body
and the radiation plate 104b and the base plate 104a making up the
antenna do not come in direct contact with each other. It may be
made of any material if the material has an insulating property;
the material is not limited.
[0106] The adhesive 123 is provided for strongly fixing the living
body placement section 101 to a living body; preferably it is a
substance not giving an impetus to the living body. For example, a
known adhesive material excellent in intimate contact with the
living body placement section 101, such as double-sided adhesive
tape, an acrylic family, a rubber family, a silicone family, or a
vinyl ether family, can be used.
[0107] The transmitter 106 is attached to the living body placement
section 101 as described above, whereby the loop antenna parts 103a
and 103b are connected, forming one loop antenna 103, and the base
plate 104a and the radiation plate 104b are connected through the
circuit on the board, forming the MSA 104. When the described
biological signal transmission apparatus is placed on a living body
surface as shown in FIG. 30, the living body placement section 101
is bonded to the surface of the living body of a subject via the
adhesive 123 and the water-containing gels 121a and 121b are
attached at a first intercostal space left sternal border on a left
chest along a position 800b in such a manner that the
water-containing gels 121a and 121b are positioned through
midclavicular line and are parallel to a clavicle, as shown in FIG.
38. Thus, there is obtained biological signals 801b which is highly
corrective to ECG detected in the method of standard limb lead
(II). In addition, the stable ECG having high correction with ECG
of standard limb lead (II) can be obtained as ling as the living
body placement section is attached to area within the range of 2.5
cm apart from the 800b, or second intercostal space and it's not
always needed to position water-containing gels 121a and 121b
through midclavicular line.
[0108] Upon the attachment, as shown in FIG. 39, the
water-containing gels 121a and 121b are attached on a chest defiend
between a xiphoid process and a navel through and perpendicular to
a midsternal line so as to obtain biological signals 801a which is
highly correlative to ECG detected in the method of standard limb
lead (II).
[0109] In addition, the stable ECG having high correlation to ECG
of standard limb lead (II) can be obtained as long as the living
body placement section is attached to area within the range of 2.5
cm apart from the 800a, and it's not always needed to position
water-containing gels 121a and 121b through midsternal line.
[0110] Biological signals detected on the conductive terminals 121c
and 121d are sent through the hooks 120a and 120b to the
transmitter 106 and are processed by the electric circuitry 111 in
the transmitter 106, then are sent through the hooks 116a and 116b
to the loop antenna 103 and through the hook 118 to the MSA 104
from which the biological signals are transmitted to the receiver
(not shown) by radio.
[0111] According to the embodiment, the biological signals detected
on the electrodes 105a and 105b are transmitted by radio through
the loop antenna 103 and the MSA 104 different in characteristics,
so that the directivity can be improved, the radiation capability
can be enhanced, and the radio wave band width can be enlarged. The
loop antenna 103 and the MSA 104 are each divided into two parts,
one of which is placed in the support 102 and the other in the
transmitter 106. Thus, the transmitter 106 can be miniaturized as
compared with the case where the whole antennas are installed in
the transmitter 106.
[0112] In the embodiment, the two electrodes 105 are used, but
similar functions and advantages can be provided if one electrode
105 is used. Two loop antennas 103 each divided into two parts
(103a and 103b and 103c and 103d) may be provided in place of the
MSA 104, as shown in FIG. 19 and FIG. 20. In this case, the 103a
and 103c are placed in a direction orthogonal to each other and the
103b and 103d are placed in a direction orthogonal to each other,
whereby the directivity can be improved. In this case, the hooks
116a and 116c are connected to ends of the loop antenna parts 103b
and 103c and the hooks 116d and 116b are connected to the
transmission section 110 of the electric circuitry 111. Opposite
ends of the loop antenna parts 103b and 103c are connected to the
transmission section 110 of the electric circuitry 111.
Fifth Embodiment
[0113] FIG. 21 to FIG. 24 show a configuration example of a fifth
embodiment of the invention and FIG. 25 to FIG. 27 show a
configuration example of a sixth embodiment of the invention. Parts
identical with or similar to those previously described with
reference to FIG. 14 to FIG. 16 are denoted by the same reference
numerals in FIG. 21 to FIG. 27 and will not be discussed again in
detail.
[0114] FIG. 21 is a block diagram to show a configuration example
of the fifth embodiment of the invention. FIG. 22 is an exploded
perspective view to show a specific configuration example of a
living body placement section in FIG. 21. FIG. 23 is an external
perspective view of the living body placement section shown in FIG.
22 and a transmitter placed thereon. FIG. 24 is a schematic
representation to show placement of antennas when the transmitter
in FIG. 23 is placed on the living body placement section.
[0115] The embodiment is characterized by the fact that one antenna
603 of two antennas 603 and 604 is divided into two parts, that one
antenna division part 603a, an electrode 105, and the whole antenna
604 are placed on a support 102, and that the other antenna
division part 603b is placed in a transmitter 106, as shown in FIG.
21. In the embodiment, one electrode 105 is used and a connector
151 placed on another part of a living body is connected to an
amplification section 107 through a connector 152, but two or more
electrodes 105 may be used. In the embodiment, the antennas 603 and
604 are MSAs, one antenna 603 is divided into two parts, and only
the radiation plate 603b of the divided antenna 603 is placed in
the transmitter 106.
[0116] In FIG. 22, a radiation plate 604b like a semi-disk is fixed
to the upper face of the support 102 formed of a dielectric
material like a disk and a base plate 153 like a disk is fixed to
the lower face of the support 102 concentrically. A caulking device
154 is inserted into the radiation plate 604b of the MSA 604 from
the lower face thereof and a hook 155 for the radiation plate is
fixed to the upper end of the caulking device 154 projecting from
the radiation plate 604b by caulking.
[0117] A caulking device 156 is inserted into the base plate 153
from the lower face thereof and passes through the support 102 and
projects upward. A hook 118 for the ground plate is fixed to the
projection end by the caulking. The electrode 105 is inserted into
the center of the support 102 from the lower face thereof and
passes through the support 102 and projects upward. A hook 120 for
deriving an electrocardiographic signal is fixed to the projection
end by the caulking. Further, conductive water-containing gel 121
is attached to the lower end of the electrode 105.
[0118] The upper face of the support 102 is covered with a
disk-like insulating sheet 157 and the hooks 118, 120, and 155 pass
through the insulating sheet 157 and project upward. Likewise, the
lower face of the support 102 is covered with a disk-like
insulating sheet 122 and the electrode 105 and the water-containing
gel 121 pass through openings 153a and 122a made in the centers of
the base plate 153 and the insulating sheet 122 and project
downward.
[0119] On the other hand, the radiation plate 603b is placed in the
transmitter 106. When the transmitter 106 is placed on the support
102 through the hooks 118, 120, and 155, the radiation plate 603b
is opposed to the base plate 153 placed on the support 102, forming
one MSA 603. Since the radiation plate 604b and the base plate 153
are opposed to each other on the support 102, another MSA 604 is
formed on the support 102. The two MSAs 603 and 604 share the base
plate 153, as shown in FIG. 24.
[0120] According to the embodiment, functions and advantages almost
similar to those of the fourth embodiment can be provided. In the
fifth embodiment, one electrode 105 is installed in a living body
placement section 101, but if two electrodes 105 are installed,
they are placed in a similar manner to that shown in FIG. 15.
Sixth Embodiment
[0121] FIG. 25 is a block diagram to show a configuration example
of the sixth embodiment of the invention. FIG. 26 is an exploded
perspective view to show a specific configuration example of a
living body placement section in FIG. 26. FIG. 27 is an external
perspective view of the living body placement section shown in FIG.
26 and a transmitter placed thereon.
[0122] The embodiment basically has almost the same configuration
as the fifth embodiment except that an antenna 103 not divided into
two parts is placed in a transmitter 106 as shown in FIG. 25 or
that two electrodes 105 are provided. The number of the electrodes
105 may be one.
[0123] In FIG. 26 and FIG. 27, the antenna 103 is a loop antenna,
an antenna 104 is an MSA, the loop antenna 103 is placed in the
transmitter 106, and a base plate 104a and a radiation plate 104b
of the MSA 104 are placed in a living body placement section 101
and the transmitter 106 respectively. The attachment structure of
the base plate 104a, the electrodes 105, and an insulating plate
122 is similar to that in the fourth embodiment shown in FIG. 15.
When the transmitter 106 is placed on the living body placement
section 101, the base plate 104a and the radiation plate 104b are
opposed to each other, forming the MSA 104.
[0124] According to the embodiment, functions and advantages almost
similar to those of the fourth embodiment can be provided. In the
sixth embodiment, the number of the electrodes 105 is two, but if
one electrode 105 is used, it is placed in a similar manner to that
shown in FIG. 22.
Seventh Embodiment
[0125] A seventh embodiment of the invention will be discussed.
FIG. 28 is a block diagram to show a configuration example of the
seventh embodiment of the invention. FIG. 29 is an exploded
perspective view. In the embodiment, two loop antennas 103A and
103B and an MSA 104 are attached to a transmitter 106.
[0126] As shown in FIG. 28, a living body placement section 101
comprises a pair of electrodes 105a and 105b integrally mounted on
a support 102. The transmitter 5 contains electric circuitry 111
made up of an amplification section 107, a modulation section 108,
a power supply section 109, and a transmission section 110. The
loop antennas 103A and 103B and the MSA 104 are electrically
connected to the electric circuitry 111. The amplification section
107 and the electrodes 105 are connected electrically and
mechanically through connectors 112.
[0127] Power is supplied from the power supply section 109 to the
amplification section 107, the modulation section 108, and the
transmission section 110. When the support 102 is placed on the
living body surface of a subject, biological signals detected on
the electrodes 105a and 105b are amplified by the amplification
section 107 and are modulated by the modulation section 108, then
are sent from the transmission section 109 to the loop antennas
103A and 103B and the MSA 104. The biological signals are
transmitted by radio from the antennas 103A, 103B, and 104 to a
receiver (not shown).
[0128] As shown in FIG. 29, a board 731 is housed in a cabinet 773
consisting of an upper lid 773a and a lower lid 773b. The two loop
antennas 103A and 103B are installed so that their loop opening
faces are orthogonal to the board face of the board 731 and are
orthogonal to each other. The two loop antennas 103A and 103B are
placed in the proximity of the margins of the board 731 and are
connected to the electric circuitry 111.
[0129] The board 731 is provided with lands 732a and 732b for
guiding biological signals detected from water-containing gels 718a
and 718b and transferred through conductive terminals 718c and
718d, caulking devices 731a and 731b, and convex hooks 719a and
719b into the electric circuitry 111. The board 731 is fixed to the
lower lid 773b in parallel with the bottom face thereof by means of
caulking devices 733a and 733b inserted into holes made in the
centers of the lands 732a and 732b and holes made in projections of
the inside of the lower lid 773b from above and concave hooks 734a
and 734b corresponding to the caulking devices 733a and 733b. When
the apparatus is placed on a living body, the bottom face of the
lower lid 773b becomes almost parallel with the living body
surface, so that the opening faces of the two loop antennas 103A
and 103B become almost orthogonal to the living body surface.
[0130] Further, the MSA 104 consisting of a radiation plate 104b
and a base plate 104a placed in parallel on a dielectric support
member 735 is installed on the board 731. As described above, the
board 731 is fixed to the lower lid 773b in parallel with the
bottom face thereof. Thus, when the apparatus is placed on a living
body, the radiation plate 104b and the base plate 104a become
almost parallel with the living body surface. At this time, the
base plate 104a is nearer to the lower lid 773b side than the
radiation plate 104b is, and thus is nearer to the living body
surface than the radiation plate 104b is.
[0131] A battery storage section is provided in the rear face of
the board 731 and a battery 734 is stored in the battery storage
section.
[0132] The support 102 is formed of an insulating material like a
plate and is narrow at the center. Projections of the caulking
devices 731a and 731b are inserted into the holes made in ends of
the conductive terminals 718c and 718d placed on the lower face of
the support 102 and are fixed to the support 102 together with the
conductive terminals 718c and 718d by means of the convex hooks
719a and 719b. The conductive water-containing gels 718a and 718b
are attached to the opposite ends of the conductive terminals 718c
and 718d. Insulating sheets 720a and 720b are attached to the
bottom faces of the caulking devices 731a and 731b for electrically
insulating from a living body.
[0133] The structures and materials of the members in the
embodiment are almost similar to those of the corresponding members
used with the above-described embodiments.
[0134] According to the embodiment, the two loop antennas 103A and
103B, which are orthogonal to each other, are excellent in
directivity, and since the opening faces of the loop antennas 103A
and 103B are orthogonal to the living body surface, the sensitivity
improves and the gain can be increased. In addition, all the
antennas 103A, 103B, and 104 are contained in the transmitter, thus
the living body placement section 101 can be removed from the
transmitter 106 so that only the living body placement section 101
can be made disposable; costs for use can be reduced.
[0135] FIG. 31 (a) shows radio wave directivity of a loop antenna
1001 and a monopole antenna 1002, affected by a human body. As
shown here, when the opening face of the loop antenna is placed at
right angles to the surface of a human body, remarkably excellent
directivity is provided as compared with the case where the
monopole antenna is placed in roughly parallel with the surface of
the human body. FIG. 31 (b) is side view of the arrangement of the
loop antenna and the monopole antenna attached with the human body
along with FIG. 31 (a). FIG. 32 (a) is an illustration to show
directivity provided when the opening face of one loop antenna 1001
is placed at right angles to the surface of a human body. FIG. 32
(b) is side view of the arrangement of one loop antenna attached
with the human body along with FIG. 32 (a). FIG. 33 (a) is an
illustration to show directivity provided when the opening faces of
two loop antennas 1001 are placed at right angles to the surface of
a human body and are orthogonal to each other. FIG. 33 (b) is side
view of the arrangement of two loop antennas attached with the
human body along with FIG. 33 (a). As shown here, if two loop
antennas 1001 are provided, they make a complement to each other in
directivity and are less affected by the human body.
[0136] According to the biological signal transmission apparatus of
the present invention, when the apparatus is placed on a living
body, it can be placed so that the loop opening face of the loop
antenna becomes almost at right angles to the living body surface.
Thus, the loop opening face can hold a constant direction relative
to the living body surface and the human body, etc., does not block
the opening face, so that attenuation of radio waves because of the
effect of the human body can be lessened, the gain can be improved,
and stable directivity can be provided.
[0137] According to the biological signal transmission apparatus of
the present invention, when the apparatus is placed on a living
body, the loop opening faces of the two loop antennas become almost
at right angles to the living body surface and are placed in a
direction almost perpendicular to each other. Thus, the loop
antennas make a complement to each other in directivity and the
gain can be improved.
[0138] According to the biological signal transmission apparatus of
the present invention, at least one loop antenna is contained in
the transmitter, thus the person on whom the apparatus is placed is
not restrained as compared with an antenna placed on the outside
such as a monopole antenna (.lambda./4 antenna). The manufacturing
cost of the support supporting the electrode and placed on the
living body surface can be reduced and can be made disposable.
[0139] According to the biological signal transmission apparatus of
the present invention, at least one of the loop antennas is divided
into two parts, one loop antenna division part is placed in the
support and the other is placed in the transmitter, and the
transmitter is placed on the support, thereby putting the loop
antenna division parts into one piece. Thus, the transmitter can be
miniaturized or the loop opening face can be enlarged as compared
with the case where all loop antennas are installed in the
transmitter. Since the loop antenna is closely fixed in the
proximity of a living body with the opening face orthogonal to the
living body surface, the gain is also improved.
[0140] According to the biological signal transmission apparatus of
the present invention, the loop antenna for emitting a biological
signal is integral with the support supporting the electrode, on
which the transmitter is placed, and when the support is placed on
the living body surface, the opening face of the loop antenna
becomes almost at right angles to the living body surface, thus
attenuation of radio waves of the loop antenna can be lessened and
the gain can be improved.
[0141] According to the biological signal transmission apparatus of
the present invention, the loop antenna disposed so that the
opening face is placed in a direction almost perpendicular to the
living body surface, and the microstrip antenna having a radiation
plate and a base plate opposed in parallel with the living body
surface, the base plate being placed nearer to the living body
surface, are placed, so that attenuation of radio waves because of
the effect of the human body can be lessened and the two antennas
make a complement to each other in directivity, thus the gain can
be improved.
[0142] According to the biological signal transmission apparatus of
the present invention, the two loop antennas disposed so that the
opening faces are placed in a direction almost perpendicular to the
living body surface and are almost at right angles to each other,
and a microstrip antenna having a radiation plate and a base plate
opposed in parallel with the living body surface, the base plate
being placed nearer to the living body surface, are provided, so
that the three antennas make a complement to each other in
directivity and the gain can be improved.
[0143] According to the biological signal transmission apparatus of
the present invention, at least one of the loop antennas and the
microstrip antenna is contained in the transmitter, so that the
person on whom the apparatus is placed is not restrained as
compared with a monopole antenna, etc., placed on the outside.
Further, the manufacturing cost of the support supporting the
electrode and placed on the living body surface can be reduced.
[0144] According to the biological signal transmission apparatus of
the present invention, the loop antenna or the microstrip antenna
can be placed on the support occupying a larger area than the
transmitter, so that the loop opening area of the loop antenna can
be enlarged and the areas of the radiation plate and the base plate
of the microstrip antenna can be made large. Thus, the gain and
band width can be improved.
[0145] According to the biological signal transmission apparatus of
the present invention, the microstrip antenna having a radiation
plate and a base plate opposed in parallel with the living body
surface, the base plate being placed nearer to the living body
surface, is provided, so that the microstrip antenna placed in
parallel with the living body surface can be thinned and a large
projection such as a monopole antenna is removed from the living
body surface. Since the base plate is placed between the radiation
plate and the living body surface, the antenna performance is less
affected by the living body.
[0146] According to the biological signal transmission apparatus of
the present invention, the microstrip antenna is contained in the
transmitter, whereby the patient is not restrained as compared with
an antenna placed on the outside such as a monopole antenna.
Further, the manufacturing cost of the support supporting the
electrode and placed on the living body surface can be reduced.
[0147] According to the biological signal transmission apparatus of
the present invention, the microstrip antenna is integral with the
support and is connected to output of the electric circuitry
through a connection member and the transmitter is placed on the
support. Thus, the radiation plate and the base plate can be placed
on the support occupying a larger area than the transmitter, so
that they can be formed largely and the gain and band width can be
improved.
[0148] According to positioning of biological signal transmission
apparatus of the present invention, ECG wave which is highly
correlative to ECG detected in the method of standard limb lead
(II) can be obtained by positioning two electrodes in the vicinity
of first and second intercostal space left sternal border parallel
to clavicle on a left chest or at area defined between a xiphoid
process and a navel perpendicular to a midsternal line on a chest
that help diagnosis of ECG wave easily.
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