JP2012088232A - Water quality inspection test paper measurement apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an apparatus which image-processes a water quality inspection test paper on the basis of imaged color information by using a color imaging part and displays numerically the degree of reaction colors of the water quality inspection test paper.SOLUTION: A water quality inspection test paper measurement apparatus comprises: imaging means which images water quality inspection test paper in color, in which one or several kinds of charta are attached on a mount of the test paper; color information calculation means which calculates color information of the charta part imaged by the imaging means; color information comparison means which compares the color information of the charta part calculated by the color information calculation means with preset calibration curve data; and measured value display means which displays measured values obtained on the basis of the color information compared by the color information comparison means.

Description

  TECHNICAL FIELD The present invention relates to a water quality test paper measuring device, and more specifically, a water quality test paper measuring device that performs image processing on the reaction color of a water quality test paper using reflected light and displays the degree of the reaction color numerically. About.

For example, when performing pH measurement, chlorine concentration measurement, or urine inspection using water quality test paper in the prior art, often use water quality test paper and visually determine the color and density of the reaction color. Are inspecting.
For example, a water quality test is to measure 3 items of free residual chlorine, pH, and total alkalinity with a single water quality test paper, and the measurement principle of the free residual chlorine is Cirrin that specifically detects free residual chlorine. Based on the Gardazine method, it is distributed under the name Aquacheck (registered trademark).
The method of measurement is very simple. The test is performed by immersing a water quality test paper in water to be inspected, reacting for a certain period of time, and checking the coloration by visual comparison with a colorimetric table prepared separately.

JP 2006-234455 A

However, as explained in the prior art, the reaction color judgment using the water quality test paper is visually compared with the printed colorimetric chart (color chart) and the water color test paper. There is a problem that it is difficult to obtain an accurate value and that the judgment varies depending on the person.
Therefore, in order to solve these problems, the present measuring device has a problem that must be solved by a device that uses a color CCD (imaging means) and displays the degree of reaction color numerically by image processing. .

  In order to solve the above-mentioned problems, the water quality test strip measuring device of the present invention is configured as follows.

(1) The water quality test paper measuring device includes: an imaging unit that performs color imaging of a water quality test paper having one to several types of chemical papers mounted on a mount; and color information of the drug paper part imaged by the imaging unit The color information calculating means for calculating the color information, the color information comparing means for comparing the color information of the medicine paper portion calculated by the color information calculating means with the calibration curve data set in advance, and the color information comparing means Measurement value display means for displaying a measurement value obtained based on the color information.
(2) The water quality according to (1), wherein the color information calculation means provides a white portion as a reference in a portion other than the drug paper, and regards these fixed positions as a white portion as a reference white. Inspection test paper measuring device.
(3) The water quality test paper measuring apparatus according to (1), wherein the imaging means is installed in an oblique direction with respect to a water quality test paper that is a member to be measured.

As in the present invention, the water quality test paper is immersed in the water to be inspected, and the water quality test paper after a lapse of a certain period of time is inserted from the insertion portion, picked up by the imaging portion, image processed, and based on the color information subjected to the image processing By displaying the results numerically, it is possible to eliminate individual differences due to visual comparison with the colorimetric table as in the past.
In addition, in the past, for each one of the test papers, the coloration was determined visually, but in the invention of the present application, since it is not a visual determination, a plurality of test papers can be simultaneously imaged and numerically displayed. Inspection efficiency can be improved and rapid processing can be performed.

It is the perspective view which showed the external appearance of the water quality test paper measuring device of this invention. FIG. 2 is an explanatory view showing the internal structure of Example 1 in a sectional view. It is explanatory drawing which showed the internal structure by sectional drawing. It is explanatory drawing which showed the internal structure by sectional drawing. It is a top view of the water quality inspection test paper which affixed three types of medicine paper on the mount. It is a side view of a water quality test paper. It is explanatory drawing which shows a mode that the part of a medical paper and the part of a mount are identified from the image taken in with the imaging means. It is a flow which shows a mode that the water quality test paper taken in with the imaging means is measured. It is explanatory drawing which showed the internal structure of Example 2 with sectional drawing.

  An embodiment of a water quality test strip measuring device according to the present invention will be described below with reference to the drawings.

  As shown in FIGS. 1 to 4, the water quality test paper measuring device according to the present invention is connected to an information device 11 such as a personal computer via a USB cable 12. An insertion positioning unit 14 that inserts and positions the water quality test paper 21 in a removable manner, and a medicine paper that is a reaction part of the water quality test paper 31 mounted on the insertion positioning unit 14 at the upper part of the base 13 is imaged. An imaging unit 15 provided at an upper position where the imaging unit 15 can be provided, and an irradiation unit 15 that irradiates light in the direction of the water quality test paper 31 positioned on both sides of the imaging unit 15 are provided.

  The insertion positioning unit 14 is provided in a concave shape on the base 13, and the water quality test paper 21 is inserted into the area that can be imaged by the imaging unit 15 inside the cover 17, and the tip side comes into contact therewith. A reference white detection unit 19 is provided which is formed by surface-treating the position adjacent to the position where the test paper 21 is positioned in white so that the water quality inspection test paper 31 does not fall off at the end of the cover 17. A mold-shaped test paper drop prevention plate 18 is provided, and a guide portion 22 formed in a recess is provided on the rear end side where the water quality test paper 31 is inserted so that the water quality test paper 31 can be easily held by hand. It has become.

  The imaging unit 15 is a so-called color CCD, is attached to the substrate 23, and has a configuration in which an imaging direction is fixed and imaging can be performed from above the test paper 31 mounted on the insertion positioning unit 14.

  The irradiating unit 16 is configured by a so-called LED, and has a configuration in which two LEDs are provided with the imaging unit 15 interposed therebetween, and has a configuration in which a diffusion plate 24 is provided on the irradiation side of the LED. With the configuration in which the diffusion plate 24 is provided, the light beam emitted from the LED is diffused by the diffusion plate 24, and the light beam toward the water quality test paper 31 is uniformly irradiated.

As shown in FIGS. 5 and 6, the water quality test paper 31 is formed in a stick shape, and is formed on a base 32 formed mainly in white, with a first medicine paper 33 a and three medicine papers that are three medicine papers at equal intervals. A second medicine paper 33b and a third medicine paper 33c are attached to each other. The number of the medical papers is determined according to the one to be inspected, and there is one paper.
In the embodiment, three medicine sheets, a first medicine paper 33a, a second medicine paper 33b, and a third medicine paper 33c are attached to the mount 32, and the first medicine paper 33a has a pH, The second chemical paper measures free residual chlorine, and the third chemical paper measures total alkalinity.

  In such a configuration, when the water quality test paper 31 is inserted into the insertion positioning unit 14, the distal end side comes into contact with the wall of the recess and is positioned at a position where the imaging unit 15 can capture an image.

Data of the water quality test paper 31 photographed by the image capturing unit 15 is taken into the information device 11 via the USB cable 12. The data on the test paper 31 is processed by the processing software installed in the information device 11.
The information device 11 such as a personal computer captures R / G / B data, which is data of the test paper 31 photographed by the imaging unit 15, and compares the background color difference between the portion of the base 32 of the test paper 31 and the main body of the test paper 31. , Detecting the shadow outline generated by the thickness of the medicine paper (first medicine paper 33a, second medicine paper 33b, third medicine paper 33c) affixed to the mount 31, and the medicine of the test paper 31 The medicine paper judgment flow for judging that the paper portion is present is installed.
Further, since the reference white differs due to individual differences between the irradiation unit 16 and the imaging unit 15, a white correction flow is mounted to correct this. Specifically, the reference white detection unit 19 that is a portion between the medicine sheets 33a, 33b, and 33c attached to the mount 32 of the mounted test paper 31 or adjacent to the positioned test paper 21 is used. The surface is treated with white and these fixed positions are defined as white portions as reference whites.
Further, measurement is performed by taking R, G, B data of each of the medical papers 33a, 33b, 33c of the test paper 31 based on the imaged R, G, B data and calculating a measurement value based on a predetermined calibration curve. A value calculation flow is installed.
And the display flow which displays the calculated measured value is mounted.

  A flow for calculating a measurement value from the test paper 31 using the information device 11 equipped with these various flows will be described below with reference to the CCD test paper / measurement flow shown in FIG.

  First, when starting the measurement, the water quality test paper 31 immersed in the water to be inspected is inserted into the insertion positioning unit 14 and positioned and set (step ST1).

  Next, on the information equipment 11 side, the test paper 31 is mounted by acquiring R / G / B data imaged by the imaging unit 15 that the water quality test paper 31 is mounted on the insertion positioning unit 14. Is detected (step ST2).

Then, the position of the test paper 31 is detected based on the R, G, B data acquired from the imaging unit 15 in step ST2 (step ST3).
That is, as shown in FIG. 7, from the R, G, B data acquired from the imaging unit 15, the color information of the mount portion of the test paper 31 and the difference in the background color of the test paper, and the medical paper pasted on the mount 32 A shadow outline or the like generated by the thicknesses 33a, 33b, and 33c is detected, and it is determined that the portion is a medicine paper portion.
By recognizing in this way, accurate R / G / B data of the reaction color portion (medical paper portion) is measured even if there is a slight misalignment.

Next, R, G, B data within a certain range of the chemical paper portion of the water quality test paper 31 is extracted (step ST4).
This is because, among the R, G, and B data of the portions of the medical paper 33a, 33b, and 33c, the data at the corners of the medical paper 33a, 33b, and 33c is not preferable as the reaction color, and thus the medical paper 33a, 33b, The R, G, B data of the central portion 33c is extracted.

Next, the R, G, B data of the central part of the medical papers 33a, 33b, 33c is homogenized (step ST5).
If the reaction color is a spotted pattern or the like, the reaction color can be made accurate by homogenization.

Next, the position of the white portion is detected using the R / G / B data of the imaged water quality test strip 31 (step ST6).
In the embodiment, the white portion is a portion adjacent to the mount between the medicine paper 33a (, 33b, 33c) and the medicine paper 33b (, 33c) attached to the mount 32, or the test paper 21 that is positioned. The reference white detection unit 19 is surface-treated in white, and the color information of these fixed positions is set as a white part. Therefore, R · G · The position of the white part is detected by extracting the B data or by extracting the R, G, B data of the reference white detection unit 19.

After detecting the position of the white part, R, G, B data of the white part is acquired (step ST7).
The reference white differs depending on individual differences such as the light source of the irradiation unit 16 and the CCD of the imaging unit 15. For this reason, since this is corrected, a white portion is provided at a fixed position, and every time RGB data is acquired, this portion of R, G, B data is taken in and used as a reference white.
This white portion can be realized by providing it in the photographing stage of the measuring instrument or by considering the mount 32 of the test paper 31 as the white portion. In the embodiment, the portion of the mount 32 is regarded as the white portion.

  Next, the obtained white, R, G, B data is homogenized (step ST8).

  A deviation value between the homogenized R, G, B data of the white portion and the true white data is calculated (step ST9).

  Then, the medicine paper is corrected by correcting the homogenized R, G, B data obtained by imaging the medicine papers 33a, 33b, 33c based on the deviation value of the white data calculated in step ST9. R, G and B data of 33a, 33b and 33c are calculated (step ST10).

Next, a measured value is calculated based on the calibration curve data belonging to the respective medicine papers 33a, 33b, and 33c attached to the mount 32 of the test paper 31 (step ST11).
In this method of calculating the measurement value, the color differs for each of the various test papers 31, and therefore, calibration curve data exists for each of the test papers 31. When determining the calibration curve data, the test paper 31 reacted with at least three different concentrations is prepared. Next, these R / G / B data is acquired from the image pickup unit (CCD) 15, homogenized R / G / B data for each density is determined, and the R / G / B data is calculated by the least square method or the like. Each calibration curve is obtained.
When calculating the measurement value, R / G / B data of the test paper 31 set each time is calculated from the calibration curve data.

When the measurement values are calculated as described above, the measurement values are displayed together with the color information as shown in FIG. 7 (step ST12).
In FIG. 7, among the three types of medical papers 33a, 33b, and 33c, for example, pH is indicated as 7pH, free residual chlorine is indicated as 2.8mg / L, and total alkalinity is indicated as 0.1mg / L.

Next, Example 2 of the water quality test strip measuring apparatus according to the present invention will be described with reference to FIG.
The water quality test paper measuring device of the second embodiment has the same configuration as that shown in the first embodiment shown in FIGS. 2 to 4, but the water quality test paper whose shooting position from the imaging unit 15 is a member to be measured. 31 is configured to take an image from an oblique direction, and irradiation from the irradiation unit 16 is also configured to irradiate the water quality test paper 31 as a member to be measured from an oblique direction. In this way, when imaging and irradiation are performed from an oblique direction, illumination is performed in a state where light is easily diffusely reflected, for example, when the measurement surface of the member to be measured 31 leaks with a glossy material or liquid. Is directly reflected and the influence of the image due to entering the light receiving unit of the imaging unit 15 can be eliminated. As a technique for eliminating this, as shown in FIG. 9, the illumination generated on the surface of the object to be measured by setting the optical axis angle θ of the camera of the imaging unit 15 to 5 degrees or more with respect to the water quality test paper 31 as the member to be measured. It is possible to prevent the directly reflected light from entering the light receiving section.
Since the other points are the same as those shown in the first embodiment shown in FIGS. 2 to 4, the same reference numerals are given and the description thereof is omitted.

In the second embodiment, the imaging unit 15 and the irradiation unit 16 are inclined with respect to the member 31 to be measured. However, the imaging unit 15 is shown in the first embodiment without being limited thereto. As described above, even if the irradiation unit 16 is irradiated from the oblique direction to the member to be measured 31 as shown in the second embodiment, the light beam from the irradiation unit 16 is irradiated. It is possible to prevent direct reflection from directly entering the imaging unit 15.
Further, as shown in the second embodiment, the image pickup unit 15 is installed so as to pick up an image from an oblique direction with respect to the member to be measured 31, and the irradiation unit 16 is substantially at the upper position of the member to be measured 31 as shown in the first embodiment. Even in the configuration in which it is positioned in the vertical direction, direct reflection of light from the irradiation unit 16 can be prevented from directly entering the imaging unit 15.

  Provided is a device that uses a color imaging unit to perform image processing based on color information obtained by imaging a water quality test paper, and displays the degree of the reaction color as a numerical value.

DESCRIPTION OF SYMBOLS 11 Information apparatus 12 USB cable 13 Base 14 Insertion positioning part 15 Imaging part 16 Irradiation part 17 Cover 18 Test paper drop prevention plate 19 Reference | standard white detection part 22 Guide part 23 Board | substrate 24 Diffusion board 31 Water quality test paper 32 Mount 33a 1st Medicine paper 33b second medicine paper 33c third medicine paper

Claims (3)

An imaging means for color-imaging a water quality test paper having one to several kinds of medical paper attached to the mount;
Color information calculating means for calculating color information of the portion of the medicine paper imaged by the imaging means;
Color information comparing means for comparing the color information of the medicine paper portion calculated by the color information calculating means with preset calibration curve data;
Measurement value display means for displaying a measurement value obtained based on the color information compared by the color information comparison means;
A water quality test strip measuring instrument.   2. The water quality test paper according to claim 1, wherein the color information calculation means provides a white portion as a reference in a portion other than the medical paper, and regards these fixed positions as white portions as reference white. Measuring device.   2. The water quality test paper measuring apparatus according to claim 1, wherein the imaging means is installed in an oblique direction with respect to a water quality test paper that is a member to be measured.

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