U.S. patent application number 15/319473 was filed with the patent office on 2017-10-26 for feces color detection device.
This patent application is currently assigned to SETECH CO., LTD.. The applicant listed for this patent is SETECH CO., LTD.. Invention is credited to Hirokazu SEKINE.
Application Number | 20170303901 15/319473 |
Document ID | / |
Family ID | 54935392 |
Filed Date | 2017-10-26 |
United States Patent
Application |
20170303901 |
Kind Code |
A1 |
SEKINE; Hirokazu |
October 26, 2017 |
FECES COLOR DETECTION DEVICE
Abstract
A plurality of color sensing sections are attached to a toilet
seat so as to test a health state or a fecal occult blood portion
every time by capturing the feces surface color during defecation.
Before feces which have been excreted from a body sink into a
water-seal portion, the circumference of the feces is optically
captured to detect the color of the surface of the feces. By
monitoring changes in color, the health state of the defecator is
monitored. In particular, by checking the presence/absence of an
occult blood portion, the present invention assists in early
detection of colorectal cancer and allows a fecal occult blood test
to be performed in a hygienic manner without burdening the
user.
Inventors: |
SEKINE; Hirokazu; (Kanagawa,
JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
SETECH CO., LTD. |
Kanagawa |
|
JP |
|
|
Assignee: |
SETECH CO., LTD.
Kanagawa
JP
|
Family ID: |
54935392 |
Appl. No.: |
15/319473 |
Filed: |
June 7, 2015 |
PCT Filed: |
June 7, 2015 |
PCT NO: |
PCT/JP2015/066420 |
371 Date: |
December 16, 2016 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
G01N 33/4833 20130101;
G01N 21/314 20130101; A61B 10/0038 20130101; G01N 2021/3144
20130101; G01N 21/84 20130101 |
International
Class: |
A61B 10/00 20060101
A61B010/00; G01N 21/31 20060101 G01N021/31; G01N 21/84 20060101
G01N021/84; G01N 33/483 20060101 G01N033/483 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 18, 2014 |
JP |
2014-125844 |
Claims
1. A feces color detection device comprising: a color sensing unit
provided on a toilet seat or an upper portion of a toilet bowl and
configured to capture an image of feces; and a color detection unit
configured to detect a color of the feces based on output signals
of the color sensing unit, the feces color detection device further
comprising: at least two different illuminators configured to
illuminate the feces, including a second illuminator emitting light
of a wavelength from 600 nm to 800 nm and a first illuminator
emitting light of a wavelength outside the wavelength region of the
second illuminator.
2. The feces color detection device according to claim 1, wherein
the color sensing unit includes an illuminator configured to
illuminate the feces, a color image-capturing camera configured to
capture an image of the feces, and a control section configured to
control the illuminator and the color image-capturing camera.
3. The feces color detection device according to claim 2, wherein
the color image-capturing camera is a linear sensor of which
light-receiving pixels are arranged in a linear array.
4. The feces color detection device according to claim 1, wherein
the color sensing unit is provided on a bottom surface of the
toilet seat.
5. The feces color detection device according to claim 1, further
comprising a color indicator unit configured to indicate a result
of the color detection unit.
6. The feces color detection device according to claim 1, wherein
the wavelength of the first illuminator is 600 nm or less and 800
nm or more, and the wavelength of the second illuminator includes
670 nm.
7. The feces color detection device according to claim 6, wherein
the color detection unit further comprises a differential signal
generation unit configured to generate a differential signal
between a first image-capturing signal obtained with light emitted
from the first illuminator and a second image-capturing signal
obtained with light emitted from the second illuminator.
8. The feces color detection device according to claim 1, further
comprising a motion detection unit configured to detect a dropping
motion of the feces.
9. The feces color detection device according to claim 1, further
comprising a recording unit configured to record the color
detection results as time-series data.
10. The feces color detection device according to claim 1,
comprising the toilet seat, and the toilet seat further comprising
a pressure sensor configured to measure a body weight.
11. The feces color detection device according to claim 1, further
comprising an excreting part washing unit, and a washed position
adjustment unit configured to adjust a position to be washed by the
excreting part washing unit based on calculated position
information, the position information representing a position of an
excreting part based on a plurality of image-capturing signals
captured by a plurality of the sensing units.
Description
TECHNICAL FIELD
[0001] The present invention relates to a device for detecting the
color of feces in the everyday life environment, monitoring the
daily health state. Particularly, the present invention relates to
a device for automatically detecting occult blood on the feces
surface.
BACKGROUND ART
[0002] Detecting occult blood in feces is effective at finding
colorectal diseases such as colorectal cancer. Fecal occult blood
detection has been employed as a test in a regular medical checkup
or a thorough medical examination and conducted in many public
institutions and medical institutions for early detection and
treatment of colorectal cancer and gastrointestinal diseases.
Methods for testing fecal occult blood include chemical methods
such as the benzidine method, the orthotolidine method and the
guaiac method, the latex agglutination method using latex particles
sensitized for an antibody and the chromatography method using a
pigment bound on an antibody.
[0003] With these fecal occult blood test methods, the user lays
sheets of paper such as toilet paper in the toilet bowl of a flush
toilet to thereafter defecate onto the toilet paper, and the user
scrapes the defecated feces with the fecal sampling pick of the
container.
[0004] With a western-style toilet, however, feces easily sink into
the water-seal portion of the toilet bowl to be mixed with urine,
making it difficult to sample feces in the toilet bowl, and the
hand may touch the feces when trying to sample the feces with the
fecal sampling pick, which is unpleasant and unsanitary.
[0005] Moreover, another problem with this method is that it is
only possible to detect an occult blood reaction from positions
where the fecal sampling pick scraped, failing to detect occult
blood in other portions, resulting in a low 50% detection rate for
early-stage colorectal cancer. Also with the low testing frequency,
i.e., thorough medical examinations and regular medical checkups,
the death rate for colorectal cancer has now risen to the third
highest for men and the highest for women, and is still on the
rise. Under such circumstances, there is an increasing demand for
the development of an examination technique that can be used in
everyday life with a high accuracy.
[0006] Methods of conducting a fecal occult blood test in a
bathroom in a hygienic manner without burdening the user include
those of Patent Document No. 1 and Patent Document No. 2, in which
feces excreted from a body are collected before the feces sink into
the water-seal portion and the collected feces are dissolved in a
solution, and the solution is transferred to detect the occult
blood in the feces-dissolved solution by an immunoassay. However,
these methods have problems such as the bad odor when collecting
the feces, cleaning of the collecting device, and the complexity in
the maintenance of the detection section.
[0007] Another method of conducting a fecal occult blood test in a
bathroom is a method in which the defecation gas discharged from
the human body during defecation is sucked in and the amine gas
contained in the sucked defecation gas is detected with an amine
sensor to detect an occult blood reaction based on the fact that
the amount of amine gas increases when there is an occult blood
reaction, as in Patent Document No. 3. With this method, the
detection accuracy is not high when no defecation gas is discharged
during defecation, and it is necessary to have a defecation gas
suction part in the vicinity of the feces and it is also necessary
to clean the tip of the suction part.
[0008] On the other hand, Patent Document No. 4 discloses an
excrement checking device for capturing the image of an excrement
in the toilet bowl and displaying the image so that the user can
view the image while in a seated position. It captures the image of
the inside of the toilet bowl with a camera, and the user can
observe the shape and the color of feces in a seated position by
looking at the monitor screen. This method merely allows the user
to look at the feces in a seated position and is not different from
looking directly at the feces with naked eyes, and there is a
problem in that the user feels reluctant to observe with naked eyes
every time.
[0009] As a method for monitoring the blood, pulse oximeters are
well known in the art that examine the degree of oxygen saturation
in the blood. This is a method of examining the blood oxygen
concentration by using the transmission intensities of near
infrared emissions of different wavelengths through blood vessels
at a finger tip, based on the difference in absorption spectrum
between oxygenated hemoglobin and deoxygenated hemoglobin. FIG. 1
shows typical absorption coefficient spectra. The vertical axis
represents the absorption coefficient, and oxygenated hemoglobin
has no absorption at 670 nm and therefore the transmitted light
appears red. Deoxygenated hemoglobin has increased absorption,
thereby appearing blackish. A pulse oximeter is a method of
examining the blood oxygen concentration based on transmitted
light.
CITATION LIST
Patent Literature
[0010] Patent Document No. 1: Japanese Laid-Open Patent Publication
No. H10-31016
[0011] Patent Document No. 2: Japanese Laid-Open Patent Publication
No. H10-260182
[0012] Patent Document No. 3: Japanese Laid-Open Patent Publication
No. 2006-132948
[0013] Patent Document No. 4: Japanese Laid-Open Patent Publication
No. 2006-61296
SUMMARY OF INVENTION
Technical Problem
[0014] With the occult blood test method using a fecal sampling
pick, which is commonly conducted in regular medical checkups and
thorough medical examinations, the test frequency is as low as one
or twice a year. Moreover, if the sampling area to be sampled with
the fecal sampling pick is small, the occult blood portion may not
be found, resulting in a low detection rate for early-stage
colorectal cancer. The method of sampling the feces with a fecal
sampling pick also has a problem of being unsanitary.
[0015] Methods in which the detection is performed during
defecation in a household toilet bowl have a problem in that the
detection is done only rarely due to the high maintenance cost of
the test, as well as other problems: the feces are sampled or the
defecation gas is sampled during defecation, not only making is
necessary to clean the sampling area, but also complicating the
maintenance of the sensor and making it necessary to provide a
means for preventing cross contamination with the subject
immediately before the test.
[0016] The color of feces is sometimes visually observed at home,
but it is a sensual determination, and it is not possible to
observe changes over days. With the fecal occult blood
determination relating to colorectal cancer, one will not notice it
until the disease advances to such a degree that it can be
recognized with naked eyes, and one may possibly overlook
early-stage cancer. Beside the occult blood determination, there is
a problem in that when the color of feces changes gradually, one
may not notice the change until the disease reaches an advanced
stage.
Solution to Problem
[0017] According to an embodiment of the present invention, a
plurality of color cameras are provided on the reverse side portion
of the toilet seat so as to capture an image of the feces surface
from a plurality of directions and observe the color of the feces
surface. The data of the feces color is recorded as time-series
data to quantitatively grasp changes in feces color. Particularly,
the presence/absence of occult blood, which is highly correlated to
colorectal cancer, is determined on a daily basis. The detection
accuracy is improved by comparison with other wavelength ranges
based on the wavelength spectrum distribution of oxygenated
hemoglobin corresponding to an occult blood reaction.
Advantageous Effects of Invention
[0018] With a feces color detection device of the present
invention, it is possible to easily observe changes in the color of
the feces surface upon defecation on a daily basis, and to detect
changes in the color of the feces surface, which is correlated to
health, particularly, occult blood, in a hygienic manner. With this
method of optically detecting occult blood on the feces surface,
cameras are provided on the reverse side of the toilet seat,
thereby enabling detection at locations away from the position of
defecation, only requiring simple maintenance of processing signals
of images captured by the cameras and requiring no special
reagents, thus facilitating daily monitoring. It also enables the
feces surface observation from a plurality of directions, making it
unlikely to overlook an occult blood reaction on the surface. An
advantage is that a test can be conducted without the user being
aware of it during defecation on a daily basis, leading to early
detection of colorectal cancer and thus decreasing the death
rate.
[0019] By using a linear sensor including three color filters of
red, blue and green as the image sensor in each color camera, it is
possible to alleviate the feeling of reluctance of being captured
by cameras during defecation. This is due to the fact that although
a linear sensor can only capture an image of a stationary object on
the same line each time, thus failing to grasp the entire image, it
can capture the surface conditions of a moving object.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] FIG. 1 shows absorption coefficient spectra of oxygenated
hemoglobin and deoxygenated hemoglobin in blood.
[0021] FIG. 2 is a side view of a toilet showing how the feces
surface is observed during defecation according to the first
embodiment of the present invention.
[0022] FIG. 3(a) is a bottom view of a toilet seat according to the
first embodiment of the present invention, FIG. 3(b) is a front
view of the toilet seat, and FIG. 3(c) is a front view of a toilet
bowl, and FIG. 3(d) is a side view of the toilet seat.
[0023] FIG. 4 is a structure diagram of a color sensing section
including an image-capturing camera, showing a light-output area
for outputting illumination light and a light-input area for
receiving image-capturing light, according to the first embodiment
of the present invention.
[0024] FIG. 5 is a view illustrating a lighting illuminator and a
light-output area for outputting illumination light according to
the first embodiment of the present invention.
[0025] FIG. 6 is a structure diagram of an image-capturing camera
in which an area sensor is used as the image-capturing element
according to the first embodiment of the present invention.
[0026] FIG. 7 is a view showing an optical relationship between a
single color sensing section of FIG. 4 and FIG. 6 and feces as the
subject, as seen from the side direction, according to the first
embodiment of the present invention.
[0027] FIG. 8 is a view showing an optical relationship between a
plurality of color sensing sections and feces as the subject, as
seen from the toilet seat bottom surface direction, according to
the first embodiment of the present invention.
[0028] FIG. 9 is a structure diagram of an image-capturing camera
in which a linear sensor and a cylindrical lens are used as the
image-capturing element according to the second embodiment of the
present invention.
[0029] FIG. 10 is a structure diagram of a color sensing section
including an image-capturing camera, showing the relative positions
over time between the light-output area for outputting illumination
light, the line of image-capturing light to be received by pixels
of the linear sensor, and feces as the subject, according to the
second embodiment of the present invention.
[0030] FIG. 11 is a diagram showing output waveforms over time of
the linear sensor according to the second embodiment of the present
invention.
[0031] FIG. 12(a) is a diagram showing conceptual output waveforms
over time of the linear sensor when the illumination wavelength is
in a wavelength range (.lamda.1) where the absorptance in blood is
high, according to the third embodiment of the present
invention.
[0032] FIG. 12(b) is a diagram showing conceptual output waveforms
over time of the linear sensor when the illumination wavelength is
in a wavelength range (.lamda.2) where the absorptance in blood is
low, according to the third embodiment of the present
invention.
[0033] FIG. 12(c) is a diagram showing conceptual differential
output waveforms over time of the linear sensor between when the
illumination wavelength is in one of two wavelength ranges
(.lamda.1 and .lamda.2) and when the illumination wavelength is in
the other wavelength range, according to the third embodiment of
the present invention.
[0034] FIG. 13(a) is a diagram showing conceptual output waveforms
over time of the linear sensor of the sensing section 3(a) in the
layout shown in FIG. 8 when the illumination wavelength is in the
wavelength range (.lamda.1) where the absorptance in blood is high,
according to the fourth embodiment of the present invention.
[0035] FIG. 13(b) is a diagram showing conceptual output waveforms
over time of the linear sensor of the sensing section 3(b) in the
layout shown in FIG. 8 when the illumination wavelength is
.lamda.1, according to the fourth embodiment of the present
invention.
[0036] FIG. 13(c) is a diagram showing conceptual differential
output waveforms over time between the linear sensors of the
sensing section 3(a) and the sensing section 3(b) in the layout
shown in FIG. 8 when the illumination wavelength is .lamda.1,
according to the fourth embodiment of the present invention.
[0037] FIG. 14(a) is a diagram showing conceptual output waveforms
over time of the linear sensor when the illumination light is
turned ON, according to the fifth embodiment of the present
invention.
[0038] FIG. 14(b) is a diagram showing conceptual output waveforms
over time of the linear sensor when the illumination light is
turned OFF, according to the fifth embodiment of the present
invention.
[0039] FIG. 14(c) is a diagram showing conceptual differential
output waveforms over time of the linear sensor between when the
illumination light is turned ON and when the illumination light is
turned OFF, according to the fifth embodiment of the present
invention.
[0040] FIG. 15 is a view showing a color indicator section
according to the seventh embodiment of the present invention.
DESCRIPTION OF EMBODIMENTS
[0041] A method for arranging cameras at positions along the toilet
seat according to an embodiment of the present invention, and a
method for detecting occult blood of a feces surface portion based
on the arrangement will now be described with reference to the
drawings. In the following description, like parts will be denoted
by like reference signs and like process names, and they will be
described in detail at first, thereafter omitting redundant
description of like parts.
Embodiment 1
[0042] FIG. 2 and FIG. 3 are views illustrating the first
embodiment of the present invention, but the concept also applies
to other embodiments.
[0043] In FIG. 2, 1 denotes a toilet bowl, with a toilet seat 2
provided thereon. A plurality of color sensing sections 3a and 3b
are provided on the reverse side of the toilet seat. The structure
is such that before feces 5 excreted from a body 4 sink into a
water-seal portion (not shown) of the toilet bowl 1, the surface of
the feces 5 is observed from a plurality of directions by means of
the color sensing sections 3a and 3b.
[0044] In the figures, broken line portions of the toilet seat 2
correspond to the end position of the opening of the toilet seat on
the inner side thereof.
[0045] The structure of the toilet seat 2 will be described in
greater detail with reference to FIG. 3. FIG. 3(a) shows the
configuration of the reverse side (the toilet bowl side) of the
toilet seat 2. A plurality of color sensing sections 3a, 3b, 3c and
3d are arranged on the reverse side of the toilet seat 2. Normally,
in order to keep the toilet seat 2 clean, a plurality of spacer
portions are provided on the reverse side portion of the toilet
seat 2 to give a spacing between the upper portion of the toilet
bowl 1 and the toilet seat 2. In FIG. 2 and FIG. 3, the color
sensing sections 3a, 3b, 3c and 3d also serve as the spacer
portions.
[0046] FIG. 3(b) is a front view of the toilet seat 2, and the
color sensing sections 3a, 3b, 3c and 3d, to serve as spacers, are
provided on the reverse side of the toilet seat 2. FIG. 3(c) is a
front view of the toilet bowl 1. The toilet seat 2 is arranged in
contact with an upper peripheral portion 1' of the toilet bowl 1
with the color sensing sections 3a, 3b, 3c and 3d therebetween.
FIG. 3(d) is a side view of the toilet seat 2.
[0047] In the figure, the broken line portions of the toilet seat 2
and the toilet bowl 1 correspond to the end portion of the opening
of the toilet seat and the toilet bowl on the inner side
thereof.
[0048] The structure of the color sensing section 3a of the toilet
seat 2 will be described with reference to FIG. 4. The structure is
also the same for the other color sensing sections 3b, 3c and 3d.
The color sensing section 3a includes, provided inside a housing 6,
an image-capturing system and an illumination system, wherein the
image-capturing system includes an image-capturing camera 7, a lens
portion 8 of the image-capturing camera and an optical window 9,
and the illumination system includes an illumination section 10 for
outputting illumination light. A light-output area 11 for
illumination light output from the illumination section 10 is
denoted by a broken line in FIG. 4, and a light-input area 12 for
receiving image-capturing light from the subject is denoted by a
dotted line in FIG. 4. A control section 13 is provided in the
housing 6, thereby synchronizing the illumination section 10 and
the image-capturing camera 7 with each other to obtain a captured
image corresponding to the illumination light.
[0049] The illumination section 10 in FIG. 4 may use a white LED,
the image-capturing camera 7 may use a Bayer-type color camera
including an arrangement of color filters of the three primary
colors (red, blue and green), a color camera of such an arrangement
that an infrared light filter is provided in a portion of the color
filter, or a filter configuration in which a portion of the color
filter is transparent light.
[0050] Ambient light coming from the gap under the toilet seat may
be used, while omitting the white LED.
[0051] The image-capturing camera may use a black-and-white camera
with no color filter, and LED illumination sections of three colors
(red, blue and green) may be successively illuminated to capture
images in a time division manner.
[0052] As for the detection of the color of feces, the color of
feces can be easily determined using conventional techniques by
calculating signal levels for the three colors (red, blue and
green) based on the captured signals of the three colors, and
comparing them with respect to the reference signal level (range)
of the color to be determined, as with ordinary color cameras.
[0053] The control section 13 of FIG. 4 is capable not only of
controlling the illumination system and the image-capturing system
of the single color sensing section 3a, but also of performing a
control in cooperation with the illumination systems and the
image-capturing systems of the color sensing sections 3b, 3c and
3d.
[0054] The structure of the illumination section 10 of FIG. 4 will
be described with reference to FIG. 5. The illumination section 10
includes illuminators 15a and 15b provided on a circuit board 14,
and a lens-shaped transparent resin 16 is used to align the output
direction of the illumination light output from the illuminator
(15a in the figure). Thus, it is possible to narrow the width of
the light-output area 11 for outputting illumination light and to
increase the intensity of the illumination light.
[0055] When LEDs are used as the illuminators 15a and 15b in the
illumination section 10 of FIG. 5, the size of the illuminator is
sufficiently smaller than the size of the lens-shaped transparent
resin 16. Therefore, by arranging the illuminators 15a and 15b in
the vicinity of each other, the light-output areas 11 for the
individual illuminators can be substantially aligned with each
other. Herein, by varying the emission wavelength between the
illuminators 15a and 15b, it is possible to obtain the output from
each pixel with respect to illumination light of different
wavelength ranges.
[0056] The structure of the image-capturing camera 7 of FIG. 4 will
be described with reference to FIG. 6. In FIG. 6, an area sensor 18
is provided, as the image-capturing element, on a circuit board
(not shown) of an image-capturing camera housing 17, and the area
sensor 18 corresponds to the lens portion 8 of FIG. 4, with a lens
19 arranged in a lens barrel 20. The image of the subject on the
lens 19 forms an image on pixels (not shown) of the area sensor.
The use of the area sensor 18 as the image-capturing element is a
characteristic of the image-capturing camera of Embodiment 1.
[0057] FIG. 7 is a view showing an optical relationship between the
single color sensing section 3a of FIG. 4 and FIG. 6 and the feces
5 as the subject, as seen from the side direction, according to the
first embodiment of the present invention. A light-output area 11a
for illumination light, denoted by a broken line, output from the
color sensing section 3a of the toilet seat 2 is reflected on the
surface of the feces 5 as the subject to be received by the color
sensing section 3a as a light-input area 12a denoted by a dotted
line. Inside the color sensing section 3a, the image of the subject
received via the optical window forms an image on pixels of the
area sensor via the lens portion.
[0058] FIG. 8 is a view showing an optical relationship between the
color sensing sections 3a, 3b, 3c and 3d of FIG. 3 and the feces 5
as the subject, as seen from the toilet seat bottom surface
direction, according to the first embodiment of the present
invention. The light-output area 11a for illumination light,
denoted by a broken line, output from the color sensing section 3a
of the toilet seat 2 is reflected on the surface of the feces 5 as
the subject to be received by the color sensing section 3a as the
light-input area 12a denoted by a dotted line. This similarly
applies to the other color sensing sections 3b, 3c and 3d, with
their light-output areas denoted as 11b, 11c and 11d and their
light-input areas as 12b, 12c and 12d.
[0059] As shown in FIG. 8, with the light-output areas for
outputting illumination light, denoted as 11a, 11b, 11c and 11d,
the entire circumference of the feces 5 as the subject is
illuminated. The light-input areas 12a, 12b, 12c and 12d for
receiving, into the color sensing section, the reflected light from
the feces 5, denoted by dotted lines, capture the entire
circumference of the feces 5 as the subject with overlap with one
another.
[0060] In FIG. 8, an occult blood area 25 is partially present on
the surface of the feces 5. With such an optical system, the occult
blood portion 25 can be detected in edge portions of the images
from the image-capturing cameras of the color sensing sections 3b
and 3d, as well as by the image-capturing camera of the color
sensing section 3a. Since the image-capturing camera is capable of
color image-capturing, such an optical system can determine the
presence/absence of blood based on the color information of the
occult blood area 25 of the feces surface.
[0061] In FIG. 5, by varying the wavelength between the
illuminators 15a and 15b, it is possible to improve the accuracy in
sensing the occult blood area 25 on the surface of the feces 5.
That is, the occult blood area can be irradiated with illumination
light of a wavelength range of red and illumination light of a
wavelength range of the complementary color of red (cyan), and it
is possible to grasp the characteristic of the color of the occult
blood area based on the output values of pixels corresponding to
the respective color filters.
Embodiment 2
[0062] As the second embodiment of the present invention, a
structure in which a linear sensor is used as the image-capturing
element of the image-capturing camera 7 of the color sensing
section will be described with reference to FIG. 9. In FIG. 9, a
linear sensor 22 is provided, as the image-capturing element, on a
circuit board 21, and with pixels 23 on the linear sensor in a
linear arrangement, it is possible to obtain linear images. For the
lens of the linear sensor, a cylindrical lens 24 is used as the
component, of which the lens size in the vertical direction and
that in the horizontal direction are significantly different from
each other as shown in FIG. 9.
[0063] FIG. 10 shows a diagram showing the structure of the color
sensing section 3a of the toilet seat 2 and the structure of the
color sensing section including the image-capturing camera
according to the second embodiment of the present invention. FIG.
10 is similar to FIG. 4 and FIG. 7 of Embodiment 1, and the
light-output area 11 for illumination light output from the
illumination section 10 is the same, but FIG. 10 is characteristic
in that the input light to be input on the pixels in a linear
arrangement, of the light-input area 12 from the feces 5 as the
subject to be received by the pixels of the linear sensor, does not
have a width and is in a linear shape, as opposed to Embodiment 1.
The light-input area 12 is denoted as a light-input area line 12'
in FIG. 10 and denoted by a one-dot-chain line so as to be
distinguished from FIG. 7 of Embodiment 1.
[0064] FIG. 10 illustrates an optical system of the color sensing
section 3a capable of detecting the occult blood portion 25 of the
feces 5 as the subject. In the figure, the elapse of time during
the downward movement of the feces 5 is represented by times t1,
t2, t3, t4 and t5. While the light-input area line 12' which can be
captured by the pixels of the linear sensor is denoted by a
one-dot-chain line, the occult blood portion 25 of the feces 5 is
captured by the linear sensor at time t3. The feces 5 as the
subject are not captured at times t1 and t5, and a part of the
feces 5 as the subject where the occult blood portion 25 is absent
is captured at times t2 and t4.
[0065] The illumination light output from the illumination section
10 and the image-capturing camera 7 for capturing an image of the
subject are synchronized with each other by means of the control
section 13 in the housing 6, as in FIG. 7, thereby making it
similarly possible to obtain a captured image corresponding to the
illumination light.
[0066] FIG. 11 shows output waveforms of the linear sensor at times
t1, t2, t3, t4 and t5 of FIG. 10. At times t1 and t5, when an image
of the feces of the subject is not being captured, a background
output is output. In the figures, the opposite ends of the pixel
output period are represented by the first pixel output (Pixel 1)
and the last pixel output (end pixel), respectively.
[0067] In FIG. 11, at times t2 and t4, when an image of the feces 5
of the subject in an area where the occult blood portion 25 is
absent, the illumination light output from the illumination section
10 is reflected by the surface of the feces 5 of the subject, which
is present at a shorter distance than the background, to return to
the sensing section. Therefore, as the output waveform, this
reflected light component from the feces surface ("feces output" in
the figures) appears, in addition to the background output, on the
light-input area line 12'. The feces output is determined by the
reflectivity of the illumination light at the feces surface and the
intensity of the illumination light at the feces surface
portion.
[0068] In FIG. 11, at time t3, when an image of the occult blood
portion 25 of the feces 5 is captured, the illumination light
output from the illumination section 10 passes through the occult
blood portion 25 adhering to the surface of the feces 5 and is
reflected by the feces surface to again pass through the occult
blood portion 25 and return to the sensing section. Therefore, as
the output waveform, this feces output of the occult blood portion
appears, in addition to the background output and the feces output,
on the light-input area line 12'. The feces output of the occult
blood portion is determined by the absorption coefficient of the
illumination light at the occult blood portion, the reflectivity of
the illumination light at the feces surface, and the intensity of
the illumination light at the feces surface portion. Herein, the
absorption coefficient of the illumination light at the occult
blood portion varies depending on the proportion of oxygenated
hemoglobin in the occult blood portion and the wavelength of the
illumination light, as shown in FIG. 1.
Embodiment 3
[0069] As the third embodiment of the present invention, where a
linear sensor is used as the image-capturing element of the
image-capturing camera 7 of the color sensing section, FIGS. 12(a)
and 12(b) show output waveforms of a linear sensor at times t1, t2,
t3, t4 and t5 of FIG. 10 when the wavelength of the illumination
light is varied.
[0070] Herein, sensing in which the wavelength of the illumination
light is varied in the infrared light region, which is not a
visible range, is also referred to as color sensing.
[0071] FIG. 12(a) shows output waveforms of the linear sensor at
times t1, t2, t3, t4 and t5 of FIG. 10, when the wavelength of the
illumination light is .lamda.1. The wavelength .lamda.1 of FIG.
12(a) corresponds to a wavelength range where the absorption
coefficient of the occult blood portion is large, and corresponds
to a visible range of 600 nm or less or a near infrared region
wavelength range of 800 nm or more in FIG. 1.
[0072] FIG. 12(b) shows output waveforms of the linear sensor at
times t1, t2, t3, t4 and t5 of FIG. 10, when the wavelength of the
illumination light is .lamda.2. The wavelength .lamda.2 of FIG.
12(b) corresponds to a wavelength range where the absorption
coefficient of the occult blood portion is small, and corresponds
to a wavelength range of around 670 nm in FIG. 1.
[0073] FIG. 12(c) shows output waveforms obtained as the difference
between the output waveforms of the linear sensor at times t1, t2,
t3, t4 and t5 of FIG. 10 when the wavelength of the illumination
light is .lamda.2 and those when the wavelength of the illumination
light is .lamda.1. It is possible to increase the detection
accuracy by extracting the signal of the occult blood portion
utilizing the difference depending on the wavelength of the
absorption coefficient of the occult blood portion. The signal
level difference in the absence of occult blood (deoxygenated
hemoglobin increases the absorption, appearing blackish) is
adjusted beforehand, including the difference in the sensitivity of
the image-capturing element to the wavelengths .lamda.2 and
.lamda.1, and the difference in the light intensity due to the
difference in the wavelength of the illumination light. Normally,
the adjustment is done in advance before shipping the product.
Then, when an image of the feces with occult blood is captured, it
is possible to accurately extract only the signal of the occult
blood portion as shown in FIG. 12(c).
[0074] As shown in FIG. 1, the absorptance of oxygenated hemoglobin
rapidly increases on the short wavelength side and on the long
wavelength side, with the absorptance minimized in a wavelength
range of around 670 nm. It is important to observe this portion for
the fecal occult blood reaction.
[0075] The absorption spectrum of blood is determined by hemoglobin
of red blood, which accounts for about a half the volume of blood,
as shown in FIG. 1. There are two types of hemoglobin in blood,
i.e., oxygenated hemoglobin and deoxygenated hemoglobin, and the
reflection spectrum varies depending on the amount of oxygen bound
to hemoglobin. The graph is characteristic in that oxygenated
hemoglobin has a local minimum point of absorption at 670 nm.
[0076] The typical blood oxygen saturation is 95% to 98% in the
arteries and 60% to 80% in the veins. Therefore, when occult blood
is adhering to the feces surface, if the adherent blood is arterial
blood, light is reflected by the feces surface without being
substantially absorbed in the wavelength range of 670 nm, thus
appearing red. Therefore, it is important to make a comparison
between 670 nm and other wavelength ranges.
[0077] Also when the adherent blood is venous blood, the main
component thereof is oxygenated hemoglobin, and there is a tendency
that the absorptance is locally minimized at 670 nm, but the
tendency is not as significant as that with arterial blood.
Oxygenated hemoglobin and deoxygenated hemoglobin both have a
significant difference in absorptance between a wavelength range of
600 nm or less and a 670 nm wavelength range. As shown in FIG. 1,
it is preferred that the wavelength of the illumination light is in
a range from 600 nm to 800 nm, where there is a significant
hemoglobin difference, and is particularly a single wavelength
around 670 nm, where the half-value width is narrow (20 nm to 140
nm). Using a wavelength of 670 nm, there is an about 10 times
sensitivity difference, and when deoxygenated hemoglobin is
contained, the light absorption coefficient is large, resulting in
a low sensor output signal level. On the other hand, when no
deoxygenated hemoglobin is contained, the light absorption
coefficient is small, resulting in a high sensor output signal
level. It is possible to determine the presence/absence of occult
blood from the sensor output signal level, and it is possible to
effectively give a warning of colorectal cancer and
gastrointestinal diseases.
Embodiment 4
[0078] As the fourth embodiment of the present invention, where a
linear sensor is used as the image-capturing element of the
image-capturing camera 7 of the color sensing section, FIGS. 13(a)
and 13(b) show output waveforms of the linear sensor at times t1,
t2, t3, t4 and t5 of FIG. 10, when the sensing section position is
varied (the sensing sections 3(a) and 3(c) of FIG. 8) in the
sensing section layout of FIG. 8.
[0079] FIG. 13(a) shows output waveforms of the linear sensor of
the sensing section 3(a) at times t1, t2, t3, t4 and t5 of FIG. 10,
when the wavelength of the illumination light is .lamda.1. The
wavelength .lamda.1 of FIG. 13(a) corresponds to a wavelength range
where the absorption coefficient of the occult blood portion is
large, and corresponds to a wavelength range in a visible range of
600 nm or less in FIG. 1.
[0080] FIG. 13(b) shows output waveforms of the linear sensor of
the sensing section 3(c) at times t1, t2, t3, t4 and t5 of FIG. 10,
also when the wavelength of the illumination light is .lamda.1. The
occult blood portion 25 cannot be detected by the sensing section
3(c), which does not give the feces output of the occult blood
portion at time t3.
[0081] FIG. 13(c) shows output waveforms obtained as the difference
between the output waveforms of the linear sensor of the sensing
section 3(a) and those of the linear sensor of the sensing section
3(c) at times t1, t2, t3, t4 and t5 of FIG. 10, also when the
wavelength of the illumination light is .lamda.1. It is possible to
increase the accuracy in detecting the occult blood portion
utilizing the difference depending on the presence/absence of the
occult blood portion.
Embodiment 5
[0082] As the fifth embodiment of the present invention, where a
linear sensor is used as the image-capturing element of the
image-capturing camera 7 of the color sensing section, FIG. 14(a)
shows output waveforms of the linear sensor at times t1, t2, t3, t4
and t5 of FIG. 10, when illumination light of the sensing section
having a wavelength of .lamda.1 is emitted (ON) in the sensing
section (FIG. 3(a)) layout of FIG. 8. In this case, illumination
due to ambient light is superposed, in addition to the illumination
light from the sensing section, deteriorating the accuracy in
giving the feces output of the occult blood portion.
[0083] FIG. 14(b) shows output waveforms of the linear sensor at
times t1, t2, t3, t4 and t5 of FIG. 10, when the illumination light
of the sensing section is not emitted (OFF). Since the illumination
light is not emitted, there is only illumination from ambient
light, resulting in a weak lighting intensity and a low output.
Since there is only illumination from ambient light, the wavelength
has a broad wavelength band, resulting in a poor accuracy in giving
the feces output of the occult blood portion.
[0084] FIG. 14(c) shows differential output waveforms of the linear
sensor at times t1, t2, t3, t4 and t5 of FIG. 10 between when the
illumination light of the sensing section is emitted (ON) and when
it is not emitted (OFF). By obtaining the difference from the
output when the illumination light is not emitted, i.e., when there
is only illumination from ambient light, it is possible to cancel
out. This improves the accuracy in giving the feces output of the
occult blood portion.
Embodiment 6
[0085] As the sixth embodiment of the present invention, it is
possible to increase the occult blood detection accuracy based on
the frequency distribution of the location where the occult blood
portion is detected, by recording output waveforms from a plurality
of color sensing sections 3a, 3b, 3c and 3d shown in FIG. 8 every
time, and not determining occult blood portion information only
from one time but checking it against the recorded history of the
same person. This is based on the fact that a person normally sits
in the same direction during defecation and the fact that the feces
are unlikely to rotate during the feces peristaltic movement
through the large intestine, so that once an occult blood reaction
starts to be observed, the fecal occult blood portion is repeatedly
located in the same direction.
[0086] In the sixth embodiment of the present invention, a toilet
bowl/toilet seat used by a plurality of persons needs to identify
the same person. For this, it is possible to identify the person
based on the body weight by adding a pressure sensor (not shown) to
the color sensing sections 3(a), 3(b), 3(c) and 3(d), as well as by
using an input (not shown) made by the person for each use. Data of
deviation between the plurality of pressure sensors can also be
used for identifying the person, and the color of feces can be used
for identifying the person.
[0087] In the first to sixth embodiments of the present invention,
it is necessary not only to identify the same person but also to
record and read data for the same person at a point in time after
the color sensing section. For this, a recording means (not shown)
may be provided in the control section to store data therein, or a
communication means (not shown) may be provided in the control
section to send data to a main server or a portable information
terminal so that the data is recorded/stored in the main server or
the portable information terminal.
Embodiment 7
[0088] As the seventh embodiment of the present invention, FIG. 15
shows an indicator section for indicating the color determined by
the feces color detection device. This indicator section is built
in the control section of the washing device. As for the connection
with the color sensing section, detected color information is
transmitted via wire or radio. The washing device section includes
a section for controlling the temperature of the toilet seat, a
section for controlling the temperature of the spray water, and a
section for controlling the pressure of the spray water. The color
determined by the feces color detection device can be indicated by
lighting LED lamps. This includes an LED that indicates "normal",
and other LEDs for indicating typical colors (e.g., white (green),
black, red). On the color indicator sections for these three
colors, there is a label prompting the user to take a test at a
hospital. It further includes a memory (e.g., an SD card) section
for recording detected color information. This recorded data may
also record the signal levels for red, blue and green so that the
levels of these colors can be displayed on a personal computer.
This data can be submitted to a hospital to improve the test
accuracy by taking time-series data into consideration.
Embodiment 8
[0089] Embodiments of the present invention have been described
above while focusing on the presence/absence of an occult blood
portion on the feces surface to assist in early detection of
colorectal cancer. However, the method for observing the color of
the feces surface according to the present invention can be used
not only to simply determine the occult blood portion, but also to
follow changes in the color of the feces surface for the general
health care of the person.
[0090] That is, it is believed that the color of feces contains
information of the digestive system, and not only the red coloring
due to colorectal cancer, for example, but also gastric ulcer,
duodenal ulcer, and abnormalities of the pancreas, the small
intestine and the large intestine, etc., are correlated to the
color of feces. Other than by obtaining data by capturing color
images, it is possible to determine the health state by combining
it with the LED emission wavelength of the illumination section, as
in the spectral representation of an occult blood reaction.
[0091] A deep green color indicates the possibility of a bile stone
stuck in the bile duct, jaundice, pancreatic cancer or liver
cancer, a deep black coal tar color indicates the possibility of
bleeding of the stomach, and a black color is the color of oxidized
iron in blood, indicating the possibility of gastric ulcer,
duodenal ulcer or gastric cancer. Blood is mixed in the feces,
i.e., hemorrhagic feces, indicates the possibility of troubles of
the large intestine, as well as colorectal cancer. Moreover,
bright-red blood indicates the possibility of rectal cancer.
[0092] In any of these cases, the color indicator device indicates
the color and prompts the user to take a test at a hospital so that
the user will immediately take a formal test.
[0093] A normal color of feces is yellowish brown. Then, the color
detection results may be recorded and continued observation may
take place.
Embodiment 9
[0094] Embodiments of the present invention have been described
above regarding a system in which a camera is started to
continually capture the image after a pressure sensor detects a
user sitting in place or after a test start switch is turned
ON.
[0095] However, continually capturing the image increases the power
consumption. In view of this, it is possible to detect the motion
of feces by using the camera in a low power consumption mode by
performing a binning or thinned image-capturing operation in which
the number of output pixels is reduced to compare between image
signals from different capture times. Then, immediately after a
motion is detected, an image-capturing operation in the normal
capturing mode is performed, and after the color is detected, the
system is turned OFF, thus realizing a feces color detection device
capable of an energy saving operation.
Embodiment 10
[0096] While individual embodiments of the present invention have
been described above, it is understood that each embodiment can be
used in combination with others rather than alone.
[0097] While the description above is directed to cases where the
sensing sections are provided inside the spacer portions on the
bottom surface of the toilet seat, the sensing sections may be
provided other than in the spacer portions. As for the alternative
locations to provide the sensing sections, the sensing sections may
be provided on the upper edge portion of the toilet bowl or may be
embedded in the upper portion of the toilet bowl.
[0098] When an excreting part washing device is built in the toilet
seat according to the present invention shown in FIG. 2, it is
possible to accurately detect the position of the feces through a
three-dimensional image-capturing operation by using the plurality
of sensing sections of FIG. 8. By controlling the washing direction
toward which warm water is sprayed, based on the detected position,
using a direction control device, it is possible to accurately aim
at the position to be washed.
INDUSTRIAL APPLICABILITY
[0099] As described above, with the feces color detection device of
the present invention, which observes the color of the feces
surface every time the user defecates, it is possible to detect
occult blood on the feces surface without the user being aware of
it, as well as monitoring changes in the health state. Because it
can be implemented with a simple structure without any extensive
structure, it can be used for the purpose of general health care of
a user himself/herself or for testing the health state, and may
also be used as a toilet bowl (toilet seat) at a hospital or
installed in a public bathroom, allowing a fecal occult blood
reaction to be detected very inexpensively without using any
reagent.
[0100] This enables early detection of colorectal cancer, which
sits high in the cancer death rate rankings, thus saving the
medical expense and elongating the average life span.
REFERENCE SIGNS LIST
[0101] 1 Toilet bowl [0102] 2 Toilet seat [0103] 3 Color sensing
section [0104] 4 Body [0105] 5 Feces [0106] 6 Sensing section
housing [0107] 7 Image-capturing camera [0108] 8 Lens portion
[0109] 9 Optical window [0110] 10 Illumination section [0111] 11
Light-output area [0112] 12 Light-input area [0113] 12' Light-input
area line [0114] 13 Control section [0115] 14 Circuit board for
illuminator [0116] 15 Illuminator [0117] 16 Lens-shaped transparent
resin [0118] 17 Image-capturing camera housing [0119] 18 Area
sensor [0120] 19 Lens [0121] 20 Lens barrel [0122] 21 Circuit board
for linear sensor [0123] 22 Linear sensor [0124] 23 Linear sensor
pixel [0125] 24 Cylindrical lens [0126] 25 Occult blood portion
* * * * *