JP3880057B2 - Sample characteristic measurement device - Google Patents

Description

  The present invention relates to a specimen characteristic measuring apparatus that applies light to a colored test paper that develops color when a specimen is applied, and measures the characteristics of the specimen based on the reflectance.

  Color test paper is used as a means for easily analyzing components contained in human or animal body fluids, such as blood, sweat, urine, or the like, or components contained in water and sewage, factory wastewater, or soil. Color test paper is well known as litmus paper, but a test piece containing a reagent that develops color when a specimen is applied is attached to the tip of stick-shaped paper. Yes, it is possible to analyze the components contained in the specimen from the change in color tone.

  For example, to analyze the characteristics of urine from the color change of the test piece over urine, such as butter sugar (urine sugar), protein, occult blood, urinary urobrinogen, ketone bodies, bilirubin, nitrite, leukocytes, etc. Different test pieces or test papers are commercially available for each detection target. Also, test paper for detecting metal ion concentration in drinking water and industrial wastewater, test paper for detecting nitrous acid concentration in food additives, test paper for detecting vitamin C concentration in fruit juice, etc., for chemical analysis Test papers for detecting zinc components, residual chlorine, tin components, hexavalent chromium components and the like are used.

  In order to analyze the characteristics of the specimen using these colored test papers, the inventor of the present application uses, in Patent Document 1, a portable type using a stick-like specimen component test paper having a test piece that develops color when the specimen is applied. A sample analyzer is proposed. Here, the light emitting element and the light receiving element are combined, the specimen component test paper is irradiated with light, and the reflection intensity of the returned light is detected to analyze the specimen component.

JP 2004-151082 A

  There are various ways of coloring these colored test papers. For example, a so-called urine sugar test paper that develops color by a urine sugar component contained in urine exhibits a green color and changes from light green to dark green as the urine sugar value increases. Therefore, in this case, the urine sugar value can be detected by distinguishing the shade of the color within the same color tone range.

  On the other hand, there is also a colored test paper that teaches the difference in the characteristics of the specimen by changing the color tone of the color. A typical example is a pH test paper. As is well known, when an acidic sample is applied, it develops an orange color, and when an alkaline sample is applied, it develops a blue color. Therefore, in this case, the difference in pH may not be distinguished by simply distinguishing between the shades of colors.

  Therefore, depending on the color test paper, it may not be sufficient for analysis of the specimen to simply illuminate the light and simply compare the reflected light intensity.

  An object of the present invention is to provide a specimen characteristic measuring apparatus capable of measuring specimen characteristics in more detail using a colored test paper whose color tone changes depending on the specimen characteristics.

1. Principle of the Present Invention The present invention is based on an investigation and experiment on how color development differs depending on the pH of a specimen on a pH test paper, and the following results are obtained. FIG. 1 is a diagram showing a change in coloration due to a difference in pH in a pH test paper. In this example, the color change from orange to blue is drastically changed with respect to a difference from pH5 to pH9. It has been shown. Therefore, it is easy to discriminate between acidic and alkaline when viewed qualitatively with the naked eye. However, there is a problem to distinguish this by the difference in reflectance.

  FIG. 2 shows experimentally the wavelength characteristics of the pH test paper of FIG. 1, the horizontal axis representing the wavelength of light and the vertical axis representing the reflectance at that wavelength, and the difference in pH. Thus, it has been found that the wavelength characteristics are complicatedly changed due to the difference in pH. For example, at a wavelength of 450 nm, the reflectance is the highest when a specimen having a pH of 9 is applied, and the reflectance is smallest when a specimen having a pH of 5 is applied. On the other hand, at a wavelength of 650 nm, the reflectance is the highest when a specimen having a pH of 5 is applied, and the reflectance is smallest when a specimen having a pH of 9 is applied. Further, in the wavelength range from 500 nm to 550 nm, the change in reflectance is not unidirectional with respect to the change in pH, and the order of change is disturbed.

  As described above, it was found that the order of the change in reflectance with respect to the change in pH is greatly different depending on how the detection wavelength band is taken. Therefore, it is difficult to distinguish the pH of the specimen by simply comparing the reflectances.

  However, by examining the data in FIG. 2 in detail, it can be seen that the following method is possible. For example, it is convenient to use a blue to green wavelength test paper for analysis of urine sugar components. For example, when paying attention to a wavelength of 530 nm, the order of the magnitude of the pH and the order of the reflectance for the pH of 6 or less. However, when the pH is 7 or higher, the reflectivity decreases as the pH increases. On the other hand, when focusing on an orange wavelength, for example, 650 nm, which is often used as an LED (Light Emission Diode), the change in reflectance due to the difference in pH is close to saturation at pH 8 or higher, but the reflectance decreases as pH decreases at pH 7 or lower. Becomes bigger.

  In other words, when an acidic sample with a low pH is applied, the reflectance changes in one direction due to the difference in pH, and when an alkaline sample with a high pH is applied, the difference in pH As a result, the reflectance changes in one direction in the blue wavelength band. Otherwise, the change in reflectance due to the difference in pH is difficult to use. Therefore, instead of using one detection wavelength band over the entire range of pH change, a detection wavelength band that is easy to use at a low pH and a detection wavelength band that is easy to use at a high pH are complemented. Thus, the pH of the specimen can be detected in more detail.

  The color of the colored test paper changes from moment to moment. Therefore, it is possible to detect the state when the color development is saturated and evaluate the characteristics of the specimen. However, it takes time to wait until saturation, and the definition of saturation is troublesome. Therefore, it is more suitable for quick and quantitative processing to determine the time from when the specimen is applied and compare the color change with time. Therefore, the time from when the specimen was put on the pH test paper was measured, and the change in reflectance over time was investigated. The results are qualitatively shown in FIGS.

In FIGS. 3 and 4, the horizontal axis indicates the time from when the specimen is placed on the pH test paper, and the vertical axis indicates the reflection intensity, and shows the time variation of the reflection intensity. Between time _{T 1} and time _{T 2,} it is about 1 second. The reflection intensity is determined by shining light on a pH test paper from a light emitting element having light emission characteristics in a wide wavelength range, and reflecting the reflected light in a blue detection wavelength band λ ₁ and an orange detection wavelength band. received at the same time and the light receiving sensitivity is good orange detecting photodiode lambda _2, it is shown by normalized output voltage value. Standardization was made so that the reflection intensity when the specimen was not applied was the same. FIG. 3 shows a state in which an acidic specimen having a low pH is put on a pH test paper, and FIG. 4 shows a state in which an alkaline specimen having a high pH is put on a pH test paper. The blue detection wavelength band λ ₁ is, for example, 530 nm, and the orange detection wavelength band λ ₂ is, for example, 650 nm.

From FIG. 3, when an acidic specimen having a low pH is placed on a pH test paper, the difference in the temporal change in reflectance due to the difference in pH is clearly seen in the orange detection wavelength band λ ₂ , but the blue detection wavelength In the band λ ₁ , the temporal change in reflectance due to the difference in pH is almost the same, and the difference is hardly recognized. On the other hand, from FIG. 4, when an alkaline specimen having a large pH is placed on a pH test paper, a difference in reflectance over time is clearly seen due to a difference in pH in the blue detection wavelength band λ ₁ . time of the reflectance due to the difference in the pH change is almost the same the difference is hardly observed in the detection wavelength band lambda _2.

A summary of the results of FIGS. 3 and 4 is shown in FIG. Here, the change rate between the time T ₁ and the time T ₂ due to the difference in pH of the specimen is shown for each detection wavelength band. Time rate of change of reflectivity, are determined based on the reflectance at time T _1. As shown in FIG. 5, in the blue detection wavelength band λ ₁ , there is no difference in the temporal change in reflectance at a low pH, but there is a difference in the temporal change in reflectance as the pH increases. Come. On the other hand, in the orange detection wavelength band λ ₂ , there is no difference in the temporal change in reflectance where the pH is high, but there is a difference in the temporal change in reflectance as the pH decreases. That is, the change in reflectance in the blue detection wavelength band λ ₁ is used for a specimen having a large pH, and the change in reflectance in the orange detection wavelength band λ ₂ is used for a specimen having a low pH. Thus, a difference in pH should be easily detectable.

Therefore, for example, a liquid having a known pH is applied to a pH test paper, and a color sample of a color corresponding to a color for a predetermined time is prepared for the reflectance that changes with time. Then, the reflectance of the color sample is measured using a reflection type optical sensor having two detection wavelength bands, and a standard table as shown in FIG. 5 is created. Next, by using the same reflective optical sensor, an unknown specimen is placed on a pH test paper, and the result of the change in reflectance with time is compared with a standard table, whereby the pH of the specimen can be specified. For example, if the measured data of the reflectance change over time is 35% in the blue detection wavelength band λ ₁ and 50% in the orange detection wavelength band λ ₂ , the characteristic of the specimen is compared with FIG. By interpolating data of the blue detection wavelength band λ ₁ having a larger reflectance change rate with respect to the difference, it can be specified that pH = 7.5. For another sample, if the blue detection wavelength band λ ₁ is 50% and the orange detection wavelength band λ ₂ is 25%, the reflectance change rate with respect to the difference in sample characteristics is large compared to FIG. By interpolating the orange detection wavelength band λ ₂ data, it can be specified that pH = 4.5.

  Based on the experimental results described above, when using a colored test paper whose color tone changes due to differences in the characteristics of the specimen, the reflectance in a plurality of detection wavelength bands is detected, and the reflectance time in each detection wavelength band Based on the change, it was found that the characteristics of the specimen can be specified in more detail. The specimen characteristic measuring apparatus according to the present invention is configured based on this principle.

2. Problem solving means The specimen characteristic measuring apparatus according to the present invention applies light to a colored test paper that develops colors with different color bands in accordance with differences in specimen characteristics when the specimen is applied, and based on the reflectance. A specimen characteristic measuring apparatus for measuring a specimen characteristic, wherein at least one of a light emitting device and a light receiving device is composed of a plurality of elements having different wavelength band characteristics, and a plurality of detection wavelengths for a colored test paper irradiated with light during a reflection type optical sensor for detecting the reflectance at the band, among the data of the reflectance at each detection wavelength band detected for color test paper sample is applied, when the reflectance with respect to differences in the characteristics of the sample And a characteristic measuring unit that selects reflectance data in a detection wavelength band having a large degree of change and obtains characteristics of the specimen from the selected reflectance data .

  In addition, the characteristic measurement unit includes a means for obtaining the time change data of the reflectance after the specimen is applied to the color test paper for each detection wavelength band, and different characteristics of the specimen with respect to the color change of the color test paper. For each of the multiple detection wavelength bands, a means for retaining the standard reflectance time variation data, and for comparing the obtained reflectance time variation data with the standard reflectance time variation data. Based on this, it is preferable to have comparison specifying means for specifying the characteristics of the specimen.

In addition, the reflective optical sensor combines a light emitting device having one light emitting element and a light receiving device having a plurality of light receiving elements having different light receiving characteristics depending on the wavelength band, or a plurality of light emitting characteristics different from each other depending on the wavelength band. A light emitting device having a light emitting element and a light receiving device having one light receiving element are preferably combined.

  In addition, the color test paper is preferably a color test paper that exhibits different color development depending on the difference in the characteristics of the specimen and has different wavelength characteristics of the color depending on the difference in the characteristics of the specimen. In addition, the color test paper is preferably a pH test paper that exhibits different color development depending on the difference in pH of the specimen and has different color characteristics of the color depending on the difference in pH of the specimen.

  As described above, according to the specimen characteristic measuring apparatus according to the present invention, the specimen characteristics can be measured in more detail using the color test paper whose color tone changes depending on the specimen characteristics.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the following, a portable device that performs pH measurement when the sample is urine will be described. However, a type other than the portable type, for example, a stationary sample characteristic measuring device may be used. Further, instead of measuring urine pH, it is possible to use a colored test paper that teaches a difference in specimen characteristics by color change. For example, as shown in FIG. 6, it may be one using a urine sugar component test paper that shows a change in urine sugar value due to a color tone change from red purple to blue purple.

  Further, the target sample for pH measurement may not be urine, but may be drinking water, industrial waste water, fruit juice, or other measurement target liquid. In addition, it is not necessary to use pH test paper as long as it teaches the specimen characteristics by color change. For example, semi-quantitative ion test paper, analytical test paper, simple water quality test paper, and the like can be targeted. Semi-quantitative ion test paper includes nitrite ion test paper for detecting nitrite concentration in food additives, nitrate ion test paper for detecting nitrate nitrogen concentration in soil, metals in drinking water and industrial wastewater. It includes a test paper for aluminum ions for detecting ion concentration, a test paper for copper ions, a test paper for metal ions such as a test paper for nickel ions, an ascorbate test paper for detecting vitamin C concentration contained in fruit juice and the like. The test paper for analysis includes zinc test paper for analyzing zinc components, chlorine test paper for analyzing residual chlorine, tin test paper for analyzing tin components, and hexavalent chromium test paper for analyzing hexavalent chromium components. Etc.

  As a sample to be applied to the color test paper, for example, a liquid such as factory waste water can be used as it is as a sample. Also, for example, when targeting soil components, dry the soil to be inspected, add purified water and stir well, filter the soil solution with a suitable filter paper, etc., and use this as the sample. Can do.

  To put a sample on a color test paper, literally pour the sample onto the color test paper, and for example, collect a sample such as industrial wastewater in a container and attach the color test paper to the sample in the container. Alternatively, the specimen characteristic measuring device may be immersed.

  FIG. 7 is a diagram showing the configuration of the color test paper 100 and the portable sample characteristic measuring apparatus 110. FIG. 7A is a plan view of the sample characteristic measuring apparatus 110 and the color test paper 100 attached thereto. FIG. 7B is a cross-sectional view when the urine 104 as the specimen is put on the specimen characteristic measuring apparatus 110 to which the color test paper 100 is attached, and FIG. 7C is a specimen characteristic measuring apparatus. It is the figure which looked at 110 from the back.

  The colored test paper 100 is a stick-shaped test paper having a test piece 102 containing a reagent that develops color according to its pH when urine is applied. As described with reference to FIG. 1, the relationship between pH and coloration is such that the color tone changes according to pH.

  The portable specimen property measuring apparatus 110 includes a housing 112 that can be grasped with one hand, and has a guide groove 114 that inserts and holds a colored test paper along its longitudinal direction. In addition, a recess 116 for pouring and holding urine as a specimen is provided near the tip. The housing 112 has a waterproof structure, and a reflection type optical sensor 10 and a control IC 120 for specifying and measuring the specimen characteristic are attached to and stored in the circuit board. As will be described later, the reflection type optical sensor 10 includes a light emitting element having light emission characteristics in a wide wavelength range and a light receiving element including two light receiving elements having different detection wavelength bands. Where the reflection type optical sensor 10 is disposed, a detection window having a waterproof structure is provided, and the test piece 102 of the colored test paper 100 is set so as to come to a position corresponding to the position of the detection window. On the back side of the housing 112, a small display 118 for displaying the measurement result of the specimen characteristic is provided together with the operation buttons.

  The operation of this configuration will be described. The colored test paper 100 is inserted into the guide groove 114 and positioned so that the test piece 102 faces the detection window for the reflective optical sensor 10. Then, the user of the specimen characteristic measuring apparatus 110 holds the housing 112 with one hand and pours the urine 104 toward the recess 116. The urine 104 poured into the depression 116 passes through the gap between the guide groove 114 and the colored test paper 100, reaches the test piece 102, and causes the test piece 102 to develop color. The reflective optical sensor 10 applies light to the test piece 102 that has developed color through the detection window, receives the returned light, detects the reflectance in the two detection wavelength bands, and outputs the data to the control IC 120. The control IC 120 includes the standard table described with reference to FIG. 5 and specifically measures the pH of urine based on this and the data from the reflective optical sensor 10, and outputs the result to the small display 118.

FIG. 8 is a block diagram of a portion relating to the specimen characteristic measurement of the specimen characteristic measuring apparatus 110. The reflective optical sensor 10 includes a light emitting element 20, a light guide 30 that guides light emitted from the light emitting element 20 to the outside, and light that is emitted from the light guide 30 and strikes the test piece 102 of the colored test paper 100. Light receiving elements 50a and 50b. The light emitting element 20 is an element having light emission characteristics in a wide wavelength range, and can be constituted by an LED, for example. The light guide 30 is formed of, for example, a transparent resin in a predetermined shape, receives light from the light emitting element 20 from the bottom, and has a metal outer surface necessary to prevent light from leaking to the upper light emission port. What was coated with the film can be used. As the two light receiving elements 50a and 50b, photodiodes having different light receiving characteristics depending on the wavelength band can be used. For example, one of the light receiving element 50a and a photodiode having a detection wavelength band lambda ₁ for blue, using other light receiving element 50b as a photodiode having a detection wavelength band lambda ₂ of orange. A phototransistor can be used instead of the photodiode.

Control IC120 includes a CPU 122, a light emitting I / F 124 is an interface circuit between the light emitting element 20, and λ ₁ I / F126 is an interface circuit between the light receiving element 50a of the detection wavelength band lambda _1, detection wavelength band lambda Λ ₂ I / F 128 that is an interface circuit between the _two light receiving elements 50b, a display I / F 130 that is an interface circuit with the small display 118, and a storage unit 132 that stores a standard table having the contents described in FIG. It is comprised including. Each of these elements is connected by an internal bus.

  The CPU 122 of the control IC 120 includes a function of the teaching unit 140 for creating a standard table in advance, and a function of a characteristic measuring unit 142 for specifying the characteristics of the specimen in comparison with the standard table. These functions can be realized by software, specifically, by executing a corresponding specimen characteristic measurement program. Moreover, you may comprise so that a part of each function may be implement | achieved by hardware.

  The operation of such a configuration, particularly the contents of each function of the CPU 122, will be described with reference to the flowcharts of FIGS. FIG. 9 is a flowchart of the teaching procedure for creating the standard table, and shows the contents of the processing procedure in the teaching unit of the CPU 122. FIG. 10 is a flowchart of the characteristic measurement procedure, and shows the contents of the processing procedure in the characteristic measurement unit of the CPU 122.

The standard table can also be created by using a reflection type optical sensor having two detection wavelength bands and measuring a change in reflectance with time by placing a specimen having a known pH on a pH test paper. However, it is preferable that teaching is performed as necessary, and that the change with time of the reflective optical sensor can be calibrated at all times. Therefore, instead of applying the specimen to the pH test paper every time teaching is performed, a color sample having a value equal to the rate of change in reflectance with time at each pH is prepared in advance, and this color sample is divided into two detection wavelength bands. Teaching is performed by measuring with a reflective optical sensor. To prepare a color sample, first place a specimen whose pH is known in advance on a pH test paper, measure the color development at the time T ₁ from when the specimen was placed as a standard, and make it the same color as that. A T ₁ color sample is prepared, and similarly, the color development at the time T ₂ elapsed from when the specimen is applied is measured as a standard, and the T ₂ color sample is prepared so as to have the same color. That is, the color sample, for each pH, is prepared and T ₁ color samples and T ₂ color samples as a set. The times T ₁ and T ₂ are preferably set within a period in which the color of the test piece 102 changes suddenly. For example, T ₁ can be set 1 second after applying the sample, and T ₂ can be set 1 second after T ₁ , that is, 2 seconds after applying the sample. Hereinafter, a teaching procedure using this color sample will be described.

In the teaching process, first, a new color test paper is prepared (S10). Specifically, a pH test paper that is the color test paper 100 is set in the specimen property measuring apparatus 110. Here, initial setting of the specimen characteristic measuring apparatus 110 is performed. The initial setting includes sensitivity adjustment of the two light receiving elements 50a and 50b. Specifically, sensitivity adjustment is performed to normalize the reflectance output values of the two light receiving elements 50a and 50b by applying light from the light emitting element 20 using the color test paper 100 on which no specimen is applied. Done. As a result, the calculation of the reflectance change rate is standardized. When the initial setting is completed, the reflectance of the color sample in the detection wavelength band λ ₁ and the detection wavelength band λ ₂ is measured. Color samples, as described above, and T ₁ color samples for each pH, two of T ₂ color samples used. Here, since color samples having different pH values are used sequentially, they are distinguished by order i. First, a color sample of i = 1 is prepared (S12). Specifically, in response to pH = 4,5,6,7,8,9, and _{T 1} color samples respectively, _{T 2} and intended to comprise color samples as one set, if used in this order, First, one set of pH 4 color samples is prepared with i = 1.

Then, the T ₁ color sample is set in the specimen characteristic measuring apparatus 110, and the reflectances in the detection wavelength band λ ₁ and the detection wavelength band λ ₂ are measured (S14). Specifically, the control unit 120 issues a light emission instruction to the light emitting element 20 via the light emission I / F 124, shines light on the T ₁ color sample through the detection window, and sets the reflectance of the returning light to λ _1. Obtained via I / F 126 and λ ₂ I / F 128. Next, similarly, the T ₂ color sample is set in the specimen characteristic measuring apparatus 110, and the reflectances in the detection wavelength band λ ₁ and the detection wavelength band λ ₂ are measured (S16).

When the reflectance in the detection wavelength band λ ₁ and the detection wavelength band λ ₂ is detected and acquired at T ₁ and T ₂ , respectively, the change rate of the reflectance in the detection wavelength band λ ₁ and the detection wavelength band λ ₂ is obtained from these. Is calculated (S18). As the change rate of the reflectivity, {(reflectance at T ₂ ) − (reflectance at T ₁ )} / (reflectance at T ₁ ) expressed in% of absolute value can be used. The calculated result is recorded (S20). Specifically, it is recorded as the contents of a standard table stored in the storage unit 132.

  When the above processing is completed for the color sample having the characteristic i = 1, that is, the pH 4 color sample, the next color sample, that is, one set of the pH 5 color sample is prepared again as i = 2, and the above processing is performed. And record. This is repeated (S24), and it is determined whether or not the recording for all the characteristics is completed (S22). When all the recording is completed, the teaching process ends. As a result, the standard table described with reference to FIG. 5 is completed and stored in the storage unit 132.

  Next, a characteristic measurement processing procedure will be described. First, a new color test paper 100 is prepared, and an initial setting of the specimen characteristic measuring apparatus 110 is performed. This step is the same as S10 in FIG. When the initial setting is completed, a sample to be measured, that is, a sample whose pH is unknown is poured into the indent 116 of the sample characteristic measuring apparatus 110, whereby a sample whose pH is unknown is poured into the test piece 102 of the color test paper 100. (S30).

Then, as described with reference to FIGS. 3 and 4, the reflectance in the detection wavelength band λ ₁ and the detection wavelength band λ ₂ is measured at an elapsed time T ₁ after applying the specimen (S32). Specifically, the control unit 120 issues a light emission instruction to the light emitting element 20 via the light emission I / F 124, passes light through the detection window, shines light on the test piece 102 on which the specimen is applied, and reflects the returned light. The rate is obtained via λ ₁ I / F 126 and λ ₂ I / F 128. Similarly, the reflectance in the detection wavelength band λ ₁ and the detection wavelength band λ ₂ is measured at an elapsed time T ₂ after applying the specimen (S 34). Time T ₁ and T ₂ is the same as that defined when preparing a color sample. For example, T ₁ can be set 1 second after applying the sample, and T ₂ can be set 1 second after T ₁ , that is, 2 seconds after applying the sample.

Then, similarly to S18 described in FIG. 9, sample to be measured per the change rate of the reflectance at the detection wavelength band lambda ₁ and the detection wavelength band lambda ₂ is calculated (S36), and compared with the standard table ( S38). Specifically, a standard table is read from the storage unit 132 and compared with data on the sample to be measured. Based on the comparison result, the characteristics of the sample to be measured are specified (S40). In the example described above, if the reflectance change rate in the detection wavelength band λ ₁ is 35% and the reflectance change rate in the detection wavelength band λ ₂ is 50%, the characteristics of the specimen are compared with the standard table of FIG. The data of the detection wavelength band λ ₂ having the larger reflectance change rate with respect to the difference is interpolated to specify pH = 7.5. The characteristic of the specified specimen, that is, the pH value is output to the small display 118 via the display I / F 130.

  In this way, when using a color test paper such as a pH test paper whose color tone changes depending on the characteristics of the specimen, the reflectance in a plurality of detection wavelength bands is detected, and the reflectance in each detection wavelength band is detected. Based on this time change, it is possible to specify the characteristics of the specimen in more detail.

  In the above description, the reflective optical sensor has been described as a combination of a light emitting element having light emission characteristics in a wide wavelength range and a plurality of light receiving elements having different light reception characteristics depending on the wavelength band. A plurality of different light emitting elements may be combined with a light receiving element having light receiving characteristics in a wide wavelength range. Further, the light guide may be omitted if light is applied from the light emitting element to the color test paper and the reflected light is received by the light receiving element, and the efficiency is within a desired range.

It is a figure showing the change of the coloration by the difference in pH in pH test paper. It is a figure which shows the wavelength characteristic of the color change of pH test paper by the difference in pH. It is a figure explaining the mode of the time change of a reflectance when an acidic sample with small pH is put on pH test paper. It is a figure explaining the mode of the time change of a reflectance when an alkaline sample with large pH is put on pH test paper. It is a figure which shows the example of the standard table in embodiment which concerns on this invention. It is a figure explaining the urine sugar component test paper which shows the change of a urine sugar value by the color tone change from red purple to blue purple. 1 is a plan view, a cross-sectional view, and a rear view of a portable specimen characteristic measuring apparatus according to an embodiment of the present invention. It is a block diagram of the specimen characteristic measuring apparatus in the embodiment according to the present invention. It is a flowchart of the procedure of teaching in embodiment which concerns on this invention. It is a flowchart of the procedure of the characteristic measurement in embodiment which concerns on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Reflective type optical sensor, 20 Light emitting element, 30 Light guide, 50a, 50b Light receiving element, 100 Color test paper, 102 Test piece, 104 Urine, 110 Specimen characteristic measuring device, 112 Housing, 114 Guide groove, 116 Indentation, 118 small display, 120 control IC, 122 CPU, 124 light emission I / F, 126 λ ₁ I / F, 128 λ ₂ I / F, 130 display I / F, 132 storage unit, 140 teaching unit, 142 characteristic measurement unit.

Claims (5)

A specimen property measuring apparatus that illuminates a colored test paper that develops colors with different tones according to differences in specimen characteristics when the specimen is applied, and measures the specimen characteristics based on the reflectance. ,
A reflection type optical sensor, wherein at least one of the light emitting device or the light receiving device is composed of a plurality of elements having different wavelength band characteristics, and detects reflectance in a plurality of detection wavelength bands with respect to the colored test paper to which light is applied,
Among the data of the reflectance at each detection wavelength band detected for color test paper sample is applied, the reflectance of the detection wavelength band degree between a large change when the reflectance to differences in the characteristics of the sample data A characteristic measuring unit for obtaining the characteristics of the specimen from the selected reflectance data ;
A specimen characteristic measuring apparatus comprising: In the specimen characteristic measuring device according to claim 1,
The characteristic measurement unit
Means for obtaining, for each detection wavelength band, reflectance change over time after the specimen is placed on the color test paper;
For color change of the color test paper, means for holding time-dependent data of reflectance that becomes a standard for each different characteristic of the specimen and for each of a plurality of detection wavelength bands;
Based on a comparison between the obtained reflectance change over time and standard reflectance change over time, a comparison and identification means for identifying the characteristics of the specimen,
A specimen characteristic measuring apparatus characterized by comprising: In the specimen characteristic measuring device according to claim 1,
Reflective light sensor
A light emitting device having one light emitting element and a light receiving device having a plurality of light receiving elements having different light receiving characteristics depending on the wavelength band, or a light emitting device having a plurality of light emitting elements having different light emitting characteristics depending on the wavelength band; A specimen characteristic measuring apparatus comprising a light receiving device having a single light receiving element. In the specimen characteristic measuring device according to claim 1,
2. A specimen characteristic measuring apparatus, wherein the colored test paper is a colored test paper that exhibits a different color development due to a difference in characteristics of the specimen and has a different wavelength characteristic of coloration due to a difference in characteristics of the specimen. In the specimen characteristic measuring device according to claim 4,
The specimen characteristic measuring apparatus, wherein the color test paper is a pH test paper that exhibits different color development depending on a difference in pH of the specimen, and has a different wavelength characteristic of coloration due to a difference in pH of the specimen.

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