WO2020110730A1

WO2020110730A1 - Apparatus that determines achievement degree of process, determination system, determination method, and program

Info

Publication number: WO2020110730A1
Application number: PCT/JP2019/044549
Authority: WO
Inventors: Daisuke Kaneko; Motohiro Furusawa; Yasuhiro Kawasaki
Original assignee: Canon Kabushiki Kaisha
Priority date: 2018-11-28
Filing date: 2019-11-13
Publication date: 2020-06-04
Also published as: JP2020081540A

Abstract

A determination apparatus includes: measuring means for measuring a color value of a discoloration area of a test paper; holding means for holding a plurality of reference color values and thresholds, the plurality of reference color values indicating a plurality of colors of the discoloration area that correspond to a plurality of achievement degrees of a predetermined process, the thresholds respectively corresponding to pairs of two neighboring achievement degrees included among the plurality of achievement degrees; and determining means for determining the achievement degree of the predetermined process based on the measured color value of the discoloration area of the test paper measured by the measuring means, the plurality of reference color values, and the thresholds respectively corresponding to the pairs of the two neighboring achievement degrees included among the plurality of achievement degrees.

Description

APPARATUS THAT DETERMINES ACHIEVEMENT DEGREE OF PROCESS, DETERMINATION SYSTEM, DETERMINATION METHOD, AND PROGRAM

The present invention relates to a technique for determining an achievement degree of a predetermined process.

Sterilization of a sterilization target inside a container has been performed by exposing the sterilization target to such an atmosphere as high-pressure steam and hydrogen peroxide. At this time, in order to determine an achievement degree of a sterilization process for the sterilization target, a so-called chemical indicator (hereinafter, CI) for sterilization is used. The CI has a discoloration area that changes in color in accordance with a degree of achievement of a condition necessary for the sterilization process that uses a sterilizing agent (e.g., steam and hydrogen peroxide). An achievement degree of the sterilization process is determined by determining a change in the color of the discoloration area of the CI; however, when the determination is made visually, an error may occur in the determination. For this reason, Japanese Patent Laid-Open No. 2003-325646 discloses a measurement apparatus that measures an achievement degree of a sterilization process by optically reading the color of a discoloration area of a CI.

As Japanese Patent Laid-Open No. 2003-325646 is intended to determine an achievement degree of a sterilization process using a color difference between the color of the discoloration area of the CI (test paper) in an initial state and the color of the same measured after the sterilization process, it is applicable only in a case where the color of the discoloration area of the CI changes linearly in a color space. Therefore, the configuration of Japanese Patent Laid-Open No. 2003-325646 cannot be applied to arbitrary CIs that include a CI having a discoloration area whose color does not linearly change in a color space.

According to an aspect of the present invention, a determination apparatus that determines an achievement degree of a predetermined process using test paper having a discoloration area that changes in color in accordance with the achievement degree of the predetermined process is provided. The determination apparatus includes: measuring means for measuring a color value of the discoloration area of the test paper; holding means for holding a plurality of reference color values and thresholds, the plurality of reference color values indicating a plurality of colors of the discoloration area that correspond to a plurality of achievement degrees of the predetermined process, the thresholds respectively corresponding to pairs of two neighboring achievement degrees included among the plurality of achievement degrees; and determining means for determining the achievement degree of the predetermined process based on the measured color value of the discoloration area of the test paper measured by the measuring means, the plurality of reference color values, and the thresholds respectively corresponding to the pairs of the two neighboring achievement degrees included among the plurality of achievement degrees.

Further features of the present invention will become apparent from the following description of exemplary embodiments with reference to the attached drawings.

FIGS. 1A to 1C are configuration diagrams of a determination apparatus according to an embodiment.

FIG. 2 is a diagram showing a CI according to an embodiment.

FIG. 3 is a diagram showing the coordinates of a plurality of achievement degrees in a color space according to an embodiment.

FIG. 4 is an explanatory diagram of a method for determining an achievement degree according to an embodiment.

FIG. 5 is an explanatory diagram of a method for determining an achievement degree according to an embodiment.

FIG. 6 is an explanatory diagram of a method for determining an achievement degree according to an embodiment.

FIG. 7 is an explanatory diagram of a method for determining an achievement degree according to an embodiment.

FIG. 8 is an explanatory diagram of a method for determining an achievement degree according to an embodiment.

FIG. 9 is an explanatory diagram of a method for determining an achievement degree according to an embodiment.

FIG. 10 is a flowchart of processing for determining an achievement degree according to an embodiment.

Below, exemplary embodiments of the present invention will be described with reference to the drawings. Note that the following embodiments are examples, and the present invention is not limited to the contents of the embodiments. Furthermore, in each of the diagrams mentioned below, constituent elements that are not necessary for the description of the embodiments are omitted.

First Embodiment
FIGS. 1A and 1B are a side view and a front view of a determination apparatus 1 that determines a sterilization level according to the present embodiment. Also, FIG. 1C is a cross-sectional view taken along the line A-A in FIG. 1B. The determination apparatus 1 includes an insertion portion 4 for a CI 2, and a conveyance roller pair 6 that conveys the CI 2 inserted into the insertion portion 4 to a measuring position on the downstream side. As shown in FIG. 1A, when a measurer has inserted the CI 2 from the insertion portion 4, the conveyance roller pair 6 conveys the CI 2 to the measuring position indicated by a solid line in FIG. 1C. A spectrometer 3 is disposed so as to face the measuring position. The spectrometer 3 irradiates a front surface of the CI 2 with light 7, and measures a spectral reflectance of a discoloration area of the CI 2 by receiving light reflected by the same. After the measurement, the CI 2 is discharged from the determination apparatus 1 through inverse rotation of the conveyance roller pair 6. A control unit 8 controls the determination apparatus 1. The control unit 8 includes a storage unit 9 that holds various types of information used in determination of an achievement degree of a sterilization process, and a computational processing unit 10 that performs various types of computational processing and the like. The computational processing unit 10 determines a color value of the discoloration area based on the spectral reflectance measured by the spectrometer 3. Furthermore, the computational processing unit 10 determines the achievement degree of the sterilization process based on the color value of the discoloration area. The determination apparatus 1 also includes a display unit 5. The control unit 8 displays the result of determination of the achievement degree of the sterilization process on the display unit 5.

FIG. 2 shows the CI 2 according to the present embodiment. The CI 2 is sheet-shaped test paper, and has a discoloration area 21 whose front surface has been subjected to chemical treatment. The discoloration area 21 changes in color in accordance with an achievement degree of a sterilization process. In the present embodiment, the discoloration area 21 of the CI 2 is configured to have a color value C#1 in an initial state, change to a color value C#2 through a color value C#9 in accordance with the achievement degree of the sterilization process, and eventually stay constant at a color value C#10. Note that the discoloration area 21 changes continuously from the color value C#1 to the color value C#10. That is to say, the discoloration area can take color values other than the color value C#1 to the color value #10. In the following description, a degree of achievement of a condition for a color value C#k (k is an integer from 1 to 10) is regarded as an achievement degree #k. In FIG. 3, the color values C#1 to C#10 of the discoloration area 21 at the respective achievement degrees #1 to #10 are shown as coordinates in an L*a*b* color space. Note that FIG. 3 also shows the coordinates of a measured color value Ct of the discoloration area 21 of the CI 2 measured by the determination apparatus 1 in this color space.

In the following description, the color values C#1 to C#10 corresponding to the achievement degrees #1 to #10 are referred to as reference color values. Furthermore, a line segment connecting between a reference color value C#m (m is an integer from 1 to 9) and a reference color value C#m+1 in the color space is expressed as a line segment Lm(m+1). In the present embodiment, a boundary point Tm(m+1) is set in advance on the line segment Lm(m+1). Also, in the following description, a color difference between a reference color value C#k and the measured color value Ct is expressed as ΔEk. In addition, in the following description, a color value is also expressed simply as a color.

In the present embodiment, the control unit 8 determines a reference color that has the smallest color difference from the measured color Ct. In the following description, a reference color that has the smallest color difference from the measured color Ct is referred to as a first selected reference color, and an achievement degree corresponding to the first selected reference color is referred to as a first selected achievement degree. Subsequently, the control unit 8 determines whether the number of achievement degrees that neighbor the first selected achievement degree is two or one. The number of achievement degrees that neighbor the first selected achievement degree is one only when the first selected achievement degree is the achievement degree #1 or the achievement degree #10. If there is one achievement degree neighboring the first selected achievement degree, the control unit 8 uses this neighboring achievement degree as a second selected achievement degree. On the other hand, if there are two achievement degrees neighboring the first selected achievement degree, the control unit 8 uses an achievement degree corresponding to a reference color that has a smaller color difference from the measured color Ct among the reference colors corresponding to these two achievement degrees as the second selected achievement degree. Note that in the following description, a reference color corresponding to the second selected achievement degree is referred to as a second selected reference color. In FIG. 3, the reference color C#8 is the first selected reference color, and the reference color C#7 is the second selected reference color. Note that in the following description, the first selected reference color and the second selected reference color are collectively referred to as selected reference colors, and the first selected achievement degree and the second selected achievement degree are collectively referred to as selected achievement degrees. Furthermore, in the following description, a line segment between the selected reference colors is referred to as a selected line segment, and a boundary point set on the selected line segment is referred to as a selected boundary point.

The following describes how to determine an achievement degree of a sterilization process based on the measured color Ct. The following description is premised on the color space shown in FIG. 3, and the reference colors C#1 to C#10, the measured color Ct, a point of intersection, and so forth in the following description are used in the same sense as a point, that is to say, coordinates in this color space.

First, in the present embodiment, as shown in FIG. 4, a point of intersection M between a selected line segment L78 and a perpendicular line O drawn from the measured color Ct to the selected line segment L78 is obtained. Then, in the present embodiment, if the point of intersection M is located between a selected boundary point T78 and the selected reference color C#8 as shown in FIG. 4, the achievement degree #8 is determined as the achievement degree of the sterilization process based on the measured color Ct. On the other hand, if the point of intersection M is located between the selected boundary point T78 and the selected reference color C#7 as shown in FIG. 5, the achievement degree #7 is determined as the achievement degree of the sterilization process based on the measured color Ct.

The position of the boundary point Tm(m+1) on each line segment Lm(m+1) is decided through an advance experiment and the like so that the result of determination of the achievement degree is close to the actual achievement degree. With this configuration, the achievement degree can be determined with high accuracy no matter how the color of the discoloration area 21 of the test paper changes in accordance with the achievement degree, for example, even when the color does not change linearly in the color space in accordance with the achievement degree.

Note that FIGS. 4 and 5 show a case where the point of intersection between the selected line segment and the perpendicular line O from the measured color Ct to the selected line segment exists on the selected line segment. However, when an internal angle of a vertex corresponding to the first selected reference color in a triangle having vertices at the measured color Ct and two selected reference colors is an obtuse angle, that is to say, greater than 90 degrees, the perpendicular line O that has been drawn from the measured color Ct perpendicularly to the selected line segment is outside the selected line segment, and there is no point of intersection M between the perpendicular line O and the selected line segment. FIG. 6 shows such a state. In FIG. 6, there is no point of intersection between a perpendicular line O that has been drawn from the measured color Ct perpendicularly to a selected line segment L34 and the selected line segment L34. In this case, it can be determined that the achievement degree corresponding to the measured color Ct exceeds the achievement degree #4. Therefore, in the present embodiment, the selected reference colors are changed to the reference colors C#4 and C#5, and a point of intersection M between a selected line segment L45 and a perpendicular line O drawn from the measured color Ct to the selected line segment L45 is obtained as shown in FIG. 7. Then, as described above, the achievement degree of the sterilization process is determined based on a positional relationship between a selected boundary point T45 and the point of intersection M. In the example of FIG. 7, as the point of intersection M is located between the selected boundary point T45 and the selected reference color C#4, the achievement degree #4 is used as the achievement degree.

Note that in FIG. 6, as the first selected achievement degree is higher than the second selected achievement degree among the two selected achievement degrees, the achievement degree #5 that is immediately higher than the first selected achievement degree is used as a new second selected achievement degree. However, when the first selected achievement degree is lower than the second selected achievement degree among the two selected achievement degrees, an achievement degree that is immediately lower than the first selected achievement degree is used as a new second selected achievement degree. For example, assume a case where the first selected achievement degree is the achievement degree #3, the second selected achievement degree is the achievement degree #4, and an internal angle corresponding to the first selected reference color C#3 is an obtuse angle. In this case, the reference color C#2 corresponding to the achievement degree #2, which is an achievement degree neighboring the achievement degree #3 corresponding to the first selected reference color C#3 and is on the side opposite to the achievement degree #4 corresponding to the second selected reference color C#4, is used as a new selected reference color.

Note that when the first selected achievement degree is the achievement degree #1 and a vertex corresponding to the first selected reference color is an obtuse angle, there is no achievement degree that is lower than the achievement degree #1. In this case, the control unit 8 determines the first selected achievement degree as the achievement degree of the sterilization process. Similarly, when the first selected achievement degree is the achievement degree #10 and a vertex corresponding to the first selected reference color is an obtuse angle, there is no achievement degree that is higher than the achievement degree #10. In this case also, the control unit 8 determines the first selected achievement degree as the achievement degree of the sterilization process. Furthermore, in a case shown in FIG. 8, whether the selected line segment is the line segment L34 or the line segment L45, there is no point of intersection between a line O that has been drawn from the measured color Ct perpendicularly to the selected line segment and the selected line segment. In this case also, the control unit 8 determines the achievement degree #4 corresponding to the first selected reference color C#4 that has the smallest color difference from the measured color Ct as the achievement degree of the sterilization process.

Note that when the measured color Ct is located on a selected line segment connecting between the selected reference colors, the determination is made using the coordinates of the measured color Ct as a point of intersection M. In FIG. 9, which shows an example of such a case, the measured color Ct is located on a selected line segment L89. In the example of FIG. 9, as the measured color Ct is located between the selected reference color C#8 and a selected boundary point T89, the achievement degree #8 is determined as the achievement degree of the sterilization process.

FIG. 10 is a flowchart of processing for determining an achievement degree of a sterilization process according to the present embodiment. In step S10, the control unit 8 obtains a measured color Ct by determining the color of the discoloration area 21 of the CI 2 based on the result of measurement by the spectrometer 3. In step S11, the control unit 8 selects two selected reference colors, namely the first selected reference color and the second selected reference color, based on the color differences between the respective reference colors and the measured color. In step S12, the control unit 8 determines whether there is a point of intersection M between a selected line segment, which is a line segment between the selected reference colors, and a line that has been drawn from the measured color Ct perpendicularly to this selected line segment. Note that when the measured color Ct is located on the selected line segment, the coordinates of the measured color Ct are determined as the point of intersection M. If there is a point of intersection M, the control unit 8 determines an achievement degree of a sterilization process based on a positional relationship between a selected boundary point on the selected line segment and the point of intersection M in step S16. On the other hand, if there is no point of intersection M in step S12, the control unit 8 changes the second selected reference color in step S13. Specifically, a reference color corresponding to an achievement degree that neighbors the first selected achievement degree and is on the side opposite to the current second selected achievement degree from the standpoint of the first selected achievement degree is used as a new second selected reference color.

In step S14, the control unit 8 determines whether there is a point of intersection M between a selected line segment and a line that has been drawn from the measured color Ct perpendicularly to this selected line segment. If there is a point of intersection M, the control unit 8 determines the achievement degree of the sterilization process based on a positional relationship between a selected boundary point on the selected line segment and the point of intersection M in step S16. On the other hand, if there is no point of intersection M, the control unit 8 determines that the achievement degree of the sterilization process is the first selected achievement degree corresponding to the first selected reference color in step S15.

Note that the position of the boundary point Tm(m+1) can be set at any position on the line segment Lm(m+1). For example, the position of the boundary point Tm(m+1) can also be the same position as one reference color C#m+1 out of the two selected reference colors. With this configuration, the achievement degree #m is determined as long as the position (point of intersection M) representing the position of the measured color Ct projected on a selected line segment does not coincide with the reference color C#m+1. Similarly, the position of the boundary point Tm(m+1) can also be the same position as the other reference color C#m out of the two selected reference colors. Note that the configuration may be such that, when the position of the point of intersection M is the same as the position of the boundary point Tm(m+1), either the achievement degree #m or the achievement degree #m+1 is determined as the achievement degree of the sterilization process.

As described above, a plurality of reference colors corresponding to a plurality of achievement degrees are set, and a boundary point (threshold) is set on a line segment connecting between reference colors corresponding to two neighboring achievement degrees in a color space. Then, two selected reference colors are selected based on the color differences from a measured color Ct, and an achievement degree of a sterilization process is determined based on a positional relationship between a boundary point on a selected line segment connecting between these selected reference colors and the measured color Ct. With this configuration, the achievement degree of the sterilization process can be determined with high accuracy by appropriately setting the boundary points, irrespective of a trajectory of a color change that is exhibited by the discoloration area 21 in a color space of a predetermined color system in accordance with the achievement degree of the sterilization process. That is to say, although the color change that is exhibited by the discoloration area 21 in accordance with the achievement degree of the sterilization process can vary depending on the type of the CI 2, the determination apparatus 1 according to the present embodiment can determine the achievement degree of the sterilization process with high accuracy simply by changing the settings of the boundary points, irrespective of the type of the CI 2.

Regarding CI
As shown in FIG. 2, in each of the above-described embodiments, the CI 2 has the quadrilateral discoloration area 21 that is different in color from a base, and the color of this discoloration area 21 changes in accordance with an achievement degree of a sterilization process. Note that the color of the discoloration area 21 can be transparent. That is to say, the "discoloration" or "color change" of the discoloration area 21 in the present invention also includes a case where the discoloration area 21 is initially transparent and a color appears thereon in accordance with the achievement degree of the sterilization process. Similarly, the "discoloration" or "color change" of the discoloration area 21 in the present invention also includes a case where the discoloration area 21 is initially non-transparent but the discoloration area 21 becomes transparent in accordance with the achievement degree of the sterilization process. Furthermore, a base portion may be transparent.

Also, for example, the color of the discoloration area 21 may initially be the same as the color of the base. Furthermore, it is not necessary for the discoloration area 21 to uniformly change in color in its entirety in accordance with the achievement degree of the sterilization process. For example, the discoloration area 21 may, in its entirety, initially have the same color as the base, and its longitudinal portion corresponding to the achievement degree of the sterilization process may change into a color that is different from the color of the base. Note that the discoloration area 21 may be formed in such a manner that it initially has a portion that is different in color from the base, and the portion that is different in color from the base increases in length in accordance with the achievement degree of the sterilization process. Inversely, the discoloration area 21 may be formed in such a manner that the portion that is different in color from the base decreases in length as the achievement degree of the sterilization process increases.

Other Embodiments
Note that in the above-described embodiments, both of the color measurement for the discoloration area 21 of the CI 2 and the determination of an achievement degree of a sterilization process are performed within one determination apparatus 1. However, a measurement apparatus that measures a color value of the discoloration area 21 and a determination apparatus that determines the achievement degree of the sterilization process may be prepared as discrete apparatuses. In this case, the measurement apparatus and the determination apparatus are configured in such a manner that they are connected by wire or wirelessly and they can communicate with each other. Alternatively, the measurement apparatus and the determination apparatus are configured in such a manner that they can communicate via a network. That is to say, the present invention can be realized as a determination system including the measurement apparatus and the determination apparatus that can communicate with each other. The determination system can include one or more measurement apparatuses and determination apparatuses. For example, the measurement apparatus includes the spectrometer 3, determines a color value by measuring the discoloration area 21 of the CI 2, and outputs the determined color value to the determination apparatus. The determination apparatus has a plurality of reference color values corresponding to a plurality of achievement degrees and thresholds that respectively correspond to pairs of two neighboring achievement degrees, and determines an achievement degree of a sterilization process based on the obtained color value. Note that it is permissible to adopt a configuration in which, rather than determining the color value in the measurement apparatus, information for determining the color value, such as a spectral reflectance of the discoloration area 21, is measured and output to the determination apparatus, and the determination apparatus determines the color value. Also note that a general-purpose computer can be used as hardware of the determination apparatus. That is to say, the determination apparatus can be realized by causing one or more processors of the computer to execute an appropriate program. Furthermore, the present invention can also be realized as a determination method.

Also, in each of the above-described embodiments, the present invention has been described using a determination apparatus that determines an achievement degree of a sterilization process as an example. However, the present invention is applicable to determination of an achievement degree of any process that uses test paper having a discoloration area that changes in color in accordance with the achievement degree of the process.

Embodiment(s) of the present invention can also be realized by a computer of a system or apparatus that reads out and executes computer executable instructions (e.g., one or more programs) recorded on a storage medium (which may also be referred to more fully as a 'non-transitory computer-readable storage medium') to perform the functions of one or more of the above-described embodiment(s) and/or that includes one or more circuits (e.g., application specific integrated circuit (ASIC)) for performing the functions of one or more of the above-described embodiment(s), and by a method performed by the computer of the system or apparatus by, for example, reading out and executing the computer executable instructions from the storage medium to perform the functions of one or more of the above-described embodiment(s) and/or controlling the one or more circuits to perform the functions of one or more of the above-described embodiment(s). The computer may comprise one or more processors (e.g., central processing unit (CPU), micro processing unit (MPU)) and may include a network of separate computers or separate processors to read out and execute the computer executable instructions. The computer executable instructions may be provided to the computer, for example, from a network or the storage medium. The storage medium may include, for example, one or more of a hard disk, a random-access memory (RAM), a read only memory (ROM), a storage of distributed computing systems, an optical disk (such as a compact disc (CD), digital versatile disc (DVD), or Blu-ray Disc (BD)^TM), a flash memory device, a memory card, and the like.

While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions.
[0038] This application claims the benefit of Japanese Patent Application No. 2018-222688, filed on November 28, 2018, which is hereby incorporated by reference herein in its entirety.

Claims

A determination apparatus that determines an achievement degree of a predetermined process using test paper having a discoloration area that changes in color in accordance with the achievement degree of the predetermined process, the determination apparatus comprising:
measuring means for measuring a color value of the discoloration area of the test paper;
holding means for holding a plurality of reference color values and thresholds, the plurality of reference color values indicating a plurality of colors of the discoloration area that correspond to a plurality of achievement degrees of the predetermined process, the thresholds respectively corresponding to pairs of two neighboring achievement degrees included among the plurality of achievement degrees; and
determining means for determining the achievement degree of the predetermined process based on the measured color value of the discoloration area of the test paper measured by the measuring means, the plurality of reference color values, and the thresholds respectively corresponding to the pairs of the two neighboring achievement degrees included among the plurality of achievement degrees.
The determination apparatus according to claim 1, wherein
in a color space of the color value measured by the measuring means, a threshold corresponding to a pair of the two neighboring achievement degrees is located on a line segment connecting between a reference color value corresponding to one of the two neighboring achievement degrees and a reference color value corresponding to the other of the two neighboring achievement degrees.
The determination apparatus according to claim 2, wherein
in the color space, the threshold corresponding to the pair of the two neighboring achievement degrees is located on a position of the reference color value corresponding to one of the two neighboring achievement degrees, or the reference color value corresponding to the other of the two neighboring achievement degrees.
The determination apparatus according to claim 2 or 3, wherein
the determining means determines a first reference color value that has the smallest color difference from the measured color value among the plurality of reference color values,
when there are two achievement degrees that neighbor a first achievement degree corresponding to the first reference color value, the determining means determines a second reference color value that has a smaller color difference from the measured color value among reference color values corresponding to the two achievement degrees, and
when a first perpendicular line that is perpendicular to a first line segment connecting between the first reference color value and the second reference color value and that passes through the measured color value has a first point of intersection with the first line segment in the color space, the determining means determines the achievement degree of the predetermined process based on the first point of intersection and a first threshold located on the first line segment.
The determination apparatus according to claim 4, wherein
when there is one achievement degree that neighbors the first achievement degree, the determining means uses a reference color value corresponding to the one achievement degree as the second reference color value.
The determination apparatus according to claim 4 or 5, wherein
when the measured color value is located on the first line segment in the color space, the determining means determines a position of the measured color value as a position of the first point of intersection.
The determination apparatus according to any one of claims 4 to 6, wherein
the determining means determines the first achievement degree as the achievement degree of the predetermined process when the first point of intersection is located between the first reference color value and the first threshold, and determines a second achievement degree corresponding to the second reference color value as the achievement degree of the predetermined process when the first point of intersection is located between the second reference color value and the first threshold.
The determination apparatus according to claim 7, wherein
when the first perpendicular line has no point of intersection with the first line segment, the determining means determines whether there is a third achievement degree that neighbors the first achievement degree and is on a side opposite to the second achievement degree from a standpoint of the first achievement degree, and
when there is the third achievement degree, the determining means determines whether a second perpendicular line that is perpendicular to a second line segment connecting between a third reference color value corresponding to the third achievement degree and the first reference color value and that passes through the measured color value has a point of intersection with the second line segment in the color space.
The determination apparatus according to claim 8, wherein
when the second perpendicular line has no point of intersection with the second line segment, the determining means determines the first achievement degree as the achievement degree of the predetermined process.
The determination apparatus according to claim 8 or 9, wherein
when the second perpendicular line has a second point of intersection with the second line segment, the determining means determines the achievement degree of the predetermined process based on the second point of intersection and a second threshold located on the second line segment.
The determination apparatus according to claim 10, wherein
the determining means determines the first achievement degree as the achievement degree of the predetermined process when the second point of intersection is located between the first reference color value and the second threshold, and determines the third achievement degree as the achievement degree of the predetermined process when the second point of intersection is located between the third reference color value and the second threshold.
The determination apparatus according to any one of claims 8 to 11, wherein
when the third achievement degree does not exist, the determining means determines the first achievement degree as the achievement degree of the predetermined process.
A determination apparatus that determines an achievement degree of a predetermined process based on a measured color value of a discoloration area that changes in color in accordance with the achievement degree of the predetermined process, the determination apparatus comprising:
obtaining means for obtaining information indicating the measured color value;
holding means for holding a plurality of reference color values and thresholds, the plurality of reference color values indicating a plurality of colors of the discoloration area that correspond to a plurality of achievement degrees of the predetermined process, the thresholds respectively corresponding to pairs of two neighboring achievement degrees included among the plurality of achievement degrees; and
determining means for determining the achievement degree of the predetermined process based on the measured color value, the plurality of reference color values, and the thresholds respectively corresponding to the pairs of the two neighboring achievement degrees included among the plurality of achievement degrees.
The determination apparatus according to claim 13, wherein
in a color space of the measured color value, a threshold corresponding to a pair of the two neighboring achievement degrees is located on a line segment connecting between a reference color value corresponding to one of the two neighboring achievement degrees and a reference color value corresponding to the other of the two neighboring achievement degrees.
The determination apparatus according to any one of claims 1 to 14, wherein
the predetermined process is a sterilization process.
A program, wherein
when the program is executed by one or more processors included in an apparatus, the program causes the apparatus to function as the determination apparatus according to any one of claims 1 to 15.
A determination system that determines an achievement degree of a predetermined process using test paper having a discoloration area that changes in color in accordance with the achievement degree of the predetermined process, the determination system comprising:
holding means for holding a plurality of reference color values and thresholds, the plurality of reference color values indicating a plurality of colors of the discoloration area that correspond to a plurality of achievement degrees of the predetermined process, the thresholds respectively corresponding to pairs of two neighboring achievement degrees included among the plurality of achievement degrees; and
determining means for determining the achievement degree of the predetermined process based on a measured color value of the discoloration area of the test paper, the plurality of reference color values, and the thresholds respectively corresponding to the pairs of the two neighboring achievement degrees included among the plurality of achievement degrees.
The determination system according to claim 17, further comprising
measuring means for measuring a color value of the discoloration area of the test paper as the measured color value.
The determination system according to claim 17, wherein
in a color space of the measured color value, a threshold corresponding to a pair of the two neighboring achievement degrees is located on a line segment connecting between a reference color value corresponding to one of the two neighboring achievement degrees and a reference color value corresponding to the other of the two neighboring achievement degrees.
A determination method that determines an achievement degree of a predetermined process using test paper having a discoloration area that changes in color in accordance with the achievement degree of the predetermined process, the determination method comprising:
obtaining a measured color value of the discoloration area of the test paper, the obtaining being performed by obtaining means; and
determining the achievement degree of the predetermined process based on a plurality of reference color values indicating a plurality of colors of the discoloration area that correspond to a plurality of achievement degrees of the predetermined process, thresholds respectively corresponding to pairs of two neighboring achievement degrees included among the plurality of achievement degrees, and the measured color value, the determining being performed by determining means.