JP2006284412A - Method for checking measurement accuracy and apparatus for checking measuring instrument - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an apparatus and a method for checking the accuracy of a measuring instrument more easily. <P>SOLUTION: The management apparatus for accuracy of a measuring-instrument comprises a measured-value reading means for acquiring measured values measured by the measuring instrument, a reference-value selection means for selecting a first reference value from the measured values, a reference-value calculation means for calculating a second reference value from the measured values, a decision-value calculation means which determines the difference between the first reference value or the second reference value and a measured value to be a decision value, a pass/fail decision means which decides as being passed when the decision value is less than a predetermined permissible value and decides as being failed when it is not less than the permissible value to report decision results, a pass/fail decision result recording means which records the decision results on a pass/fail decision result history file, a means for calculating a fail rate by referring to the pass/fail decision result history file, and a repair decision means which gives an instruction as to calibration repair when the calculated fail rate is not less than a predetermined fail-rate permissive value. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

The present invention relates to a measurement accuracy check method and a check device for confirming that the measurement accuracy of a measuring instrument is within a guaranteed range.

In order to maintain the accuracy of the measuring instrument, it is necessary to periodically obtain a calibration certificate from an organization (for example, a measuring instrument manufacturer or an agency) that guarantees the calibration of the measuring accuracy. However, the calibration proof does not guarantee the measurement accuracy of the measuring instrument until the next calibration proof, and the user has to confirm the measurement accuracy of the measuring instrument during that time.

For example, Patent Document 1 proposes a technique for managing measurement accuracy by recording and displaying the results of time-series measurement analysis of a standard sample whose concentration is already known. (Prior art 1)

JP-A-11-94600 (pages 4-5, FIGS. 3-4)

However, in the prior art 1, since measurement is performed in time series using a standard sample whose measurement value is known in advance, measurement environment management (for example, temperature control) is performed so as to remove a variation factor that adversely affects the measurement value. Without control, humidity control, etc., there was a drawback that the measurement results could not be guaranteed.

The present invention has been made in view of such a conventional technique, and an object thereof is to provide an apparatus and a method for more easily checking the accuracy of a measuring instrument.

The present invention solves the above problems by the following means. That is, the invention according to claim 1 is characterized in that the storage means stores a pass / fail judgment result history file for recording the judgment result, and the measurement value reading means for obtaining the measurement value measured by the measuring instrument, and the acquisition A reference value selecting means for selecting a first reference value from the measured values, a reference value calculating means for calculating a second reference value from the acquired measured values, and the first reference value, or A determination value calculating means for determining a difference between the second reference value and the acquired measurement value and setting the determination value as a determination value; If it is judged as acceptable and exceeds the allowable value, it is judged as unacceptable, and the acceptance / rejection determination means for reporting the acceptance / rejection determination result, and the determination result of the acceptance / rejection is recorded in the acceptance / rejection determination result history file. And a pass / fail judgment result recording means, and the pass / fail judgment result history file Means for calculating a failure rate with reference to the data, and a repair determination means for instructing calibration and repair if the calculated failure rate is equal to or greater than a given failure rate allowable value. This is a measuring instrument quality control device.

That is, the pass / fail judgment of the measuring device is performed by comparison with the measured values of other measuring devices. The determination of whether to repair a measuring instrument that fails is based on the past failure rate.

According to a second aspect of the present invention, the first reference value is a measured value measured by a reference measuring instrument, and the second reference value is an average of measured values of measuring instruments other than the reference measuring instrument. It is a value, It is a measuring device precision management apparatus of Claim 1 characterized by the above-mentioned.

That is, the pass / fail determination of the measuring device is performed by comparison with the measured value of the reference measuring device or by comparison with the average value of the measured values.

The invention according to claim 3 is a measurement value reading step of acquiring a measurement value measured by a measuring instrument, a reference value selection step of selecting a reference value from the acquired measurement value, and the acquired measurement A reference value calculating step for calculating an average value from the value, a determination value calculating step for determining a difference between the reference value or the average value and the acquired measured value, and a determination value, and the determination value, Compared with the given tolerance value, if it is less than the tolerance value, it is judged as acceptable, if it exceeds the tolerance value, it is judged as unacceptable, and a pass / fail judgment step for reporting the judgment result of acceptance / failure, A step of calculating a failure rate with reference to the acceptance / rejection determination result history file, and a repair determination instructing calibration repair if the calculated failure rate is equal to or greater than a given failure rate allowable value And a procedure that includes A measuring instrument quality control method comprising Rukoto.

The invention according to claim 4 is a computer program that causes a computer to operate as the measuring instrument accuracy management device according to claim 1 or claim 2 by being incorporated in the computer.

The invention according to claim 5 is a computer-readable recording medium in which the program according to claim 4 is recorded.

According to the present invention, it is possible to provide a method and apparatus for easily checking the accuracy of a measuring instrument.

Hereinafter, embodiments of the present invention will be described in more detail with reference to the drawings. FIG. 1 is a detailed configuration diagram of the measuring instrument accuracy management device. The measuring instrument accuracy management apparatus 100 includes a measurement value reading unit 101, a reference value selection unit 102, an average value calculation unit 103, a determination value calculation unit 104, a measurement accuracy pass / fail determination unit 105, and a measurement accuracy pass / fail determination result recording. Means 106, repair determination means 107, and storage means 110 are provided. The storage unit 110 stores a measurement accuracy pass / fail determination result history file 110a. The measuring device 200 holds a measured value file 201a in the storage unit 210.

The measurement value reading unit 101 acquires the measurement value file 201a. The reference value selection unit 102 selects a measurement value of a desired measuring instrument from the acquired measurement value file 201a and sets it as a reference value. The average value calculation means 103 calculates the average value of the measurement values included in the acquired measurement value file 201a. The determination value calculation unit 104 calculates a determination value by obtaining a difference between the selected reference value or the calculated average value and the measurement value included in the measurement value file 201a. The measurement accuracy acceptance / rejection determination unit 105 compares the calculated determination value with a given allowable value, and determines that it is acceptable if it is equal to or less than the allowable value, and determines that it is unacceptable if the allowable value is exceeded. And report the pass / fail judgment result. The measurement accuracy pass / fail judgment result recording means 106 records the reported judgment result. The repair determination means 107 refers to the measurement accuracy pass / fail determination result history file 110a, calculates the failure rate of the measuring device, and gives an instruction for calibration and repair if the failure rate exceeds a predetermined allowable failure rate.

The storage means 110 is a non-volatile memory area built in the measuring instrument accuracy management device 100. The storage unit 210 is a non-volatile memory area built in the measuring device 200. Measurement value reading means 101, reference value selection means 102, reference value calculation means 103, determination value calculation means 104, measurement accuracy acceptance / rejection determination means 105, measurement accuracy acceptance / rejection determination result recording means 106, and repair determination means 107 Is a computer program built in the measuring instrument accuracy management apparatus 100. The pass / fail judgment result history file 110a and the measurement value file 201a are data.

FIG. 2 is a structural diagram of a measurement value file when a reference sample is measured with a measuring instrument.
The measuring device 200 (for example, a spectrophotometer) measures a reference sample (for example, a color chart), obtains a measured value by CIELab (CIE1976L ^* a ^* b ^* color space), and records it in the measured value file 201a. . The measurement value file 201a includes “color chart number” 201c and “CIELab” 201b (L value 201c, a value 201d, and b value 201e) .The spectrophotometer 200 is configured with 80 colors. The CELLab L, a, and b values are measured using the color chart as a reference sample, so the spectrophotometer can be measured in a single measurement using this color chart. , CIELab values (L value, a value, b value) can be obtained (set) 80. For example, the L value, a value, and b value of the color chart number “1” are “93.45” and “0”, respectively. Similarly, the values of the color chart number “2” are “80.23”, “−45.22”, and “1.88”, respectively, and the color chart number “ Each value of 80 "is" 7.55 " It is a 1.98 "" 3.14 ".

The reference sample is a printed matter created using DDCP (Direct Digital Color Proof) using a pigment-based color material, and is composed of an 80-color chart.

FIG. 3 is an explanatory diagram of an equation for calculating a color difference between a spectrophotometer for checking measurement accuracy and a reference spectrophotometer. Formula 311 for obtaining CIELab color difference ΔE between the spectrophotometer for checking the measurement accuracy and the reference spectrophotometer is “ΔE = ((L ₂ −L ₁ ) ² + (a ₂ −a ₁ ) ² + (b ₂ − b ₁ ) ² ) ^1/2 ". Here, “L ₁ ”, “a ₁ ”, and “b ₁ ” are CIELab values of the reference spectrophotometer, and “L ₂ ”, “a ₂ ”, and “b ₂ ” check the measurement accuracy. It is a CIELab value of a spectrophotometer.

FIG. 4 is an example of a color difference graph of a spectrophotometer for checking measurement accuracy and a reference spectrophotometer. The horizontal axis of the color difference graph 411 is the color chart number of 80 colors, and the vertical axis is the color difference value. The color difference of the spectrophotometer indicates that even the maximum color difference 411a (color difference value = 0.78) is within an allowable value of 0.8.

FIG. 5 is an explanatory diagram of an equation for calculating the color difference between the spectrophotometer for checking the average value measurement accuracy and the average value. The spectrophotometer for checking the measurement accuracy and the equation 312 for obtaining the average CIELab color difference ΔE _a are: “ΔE _a = ((L ₂ −L _ave ) ² + (a ₂ −a _ave ) ² + (b ₂ −b _ave ) ² ) ^1/2 ". Here, “L _ave ”, “a _ave ”, and “b _ave ” are average values calculated based on CIELab values of all other spectrophotometers except the reference spectrophotometer, and “L ₂ ”. And “a ₂ ” and “b ₂ ” are CIELab values of the spectrophotometer that checks the measurement accuracy.

Here, in calculating the average values “L _ave ”, “a _ave ”, and “b _ave ”, the measurement value of the spectrophotometer including the measurement value separated by 3σ or more from the standard deviation σ is excluded, and the average value is calculated. A measured value may be obtained.

FIG. 6 is an example in which the color difference between the spectrophotometer for checking the measurement accuracy and the average measurement value is graphed. The horizontal axis of the color difference graph 412 is the number of the color chart of 80 colors, and the vertical axis is the color difference value, as in FIG. The color difference of this spectrophotometer shows that even the maximum color difference 412a (color difference value = 0.52) is within an allowable value of 0.8.

FIG. 7 is an example showing the pass / fail judgment result of the spectrophotometer that checks the measurement accuracy.
The items of the pass / fail judgment result are “spectrophotometer number”, “check date”, “maximum color difference from reference value”, “maximum color difference from average measured value” and “pass / fail judgment” (breakdown “reference value judgment”) "" Average measurement value judgment "). For example, in the example of FIG. 4, the value of “maximum color difference from the reference value” is “0.78” 110b that is less than the allowable value 0.8, and therefore passes and is recorded as “go” 110d. . In the example of FIG. 6, the value of “maximum color difference from the average measurement value” is “0.52” 110c that is less than the allowable value 0.8, and therefore passes, and “go” 110e is recorded.

FIG. 8 is an example of a pass / fail judgment result history of the spectrophotometer. The items of the pass / fail judgment result history file 110a are determined to be “measurement accuracy check date”, “maximum color difference from reference value”, “maximum color difference from reference value”, “pass / fail judgment”, and “no” in the past five times. The “measurement accuracy check date” field records the measurement date, the “maximum color difference from the reference value” field, and the “average measurement value”. The maximum color difference (described later) value is recorded in the “maximum color difference” column, and the pass / fail result of the reference value determination and the average measurement value determination is recorded in the “pass / fail determination” column. Judgment "" Failure rate judged as "No" in the past 5 times "" column shows the failure rate of reference value judgment ("No" ratio for the past 5 times of the pass / fail result) and failure in average measurement value judgment The rates (the ratios of “No” for the past five pass / fail results) are shown. For example, if the number of “No” for the past five reference value determinations is 110 f, the reference value determination failure rate 110 h is “20%”, and the “No” for the past five average measurement determinations. When the number of times is 0 times 110 g, the reference value determination failure rate 110 i is “0%”.

FIG. 9 is an operation flowchart of the measuring instrument accuracy management apparatus according to the present invention.
(1) The measured value reading unit 101 acquires a measured value measured by a measuring instrument. (Step S101)
(2) The reference value selection means 102 uses the measurement value of the reference measuring instrument as the reference value. (Step S102)
(3) The reference value calculation means 103 obtains an average measurement value of the measurement values of the measuring instrument. (Step S10 03)
(4) The judgment value calculation means 104 calculates the color difference from the measured value and the reference value of the spectrophotometer for checking the measurement accuracy, and records and holds the maximum value as “the maximum color difference from the reference value”. (Step S104)
(5) The judgment value calculation means 104 calculates the color difference from the measured value and the average value of the spectrophotometer for checking the measurement accuracy, and records and holds the maximum value as “the maximum color difference from the average measured value”. (Step S105)
(6) The pass / fail judgment means 105 compares the value of the “maximum color difference from the reference value” with a predetermined allowable value, makes a pass / fail judgment, and reports the judgment result. If the value of the “maximum color difference from the reference value” is equal to or less than the allowable value, the result is passed and the process proceeds to (7). If the value of the “maximum color difference from the reference value” exceeds the allowable value, the process proceeds to (11). (Step S106)
(7) The pass / fail judgment result recording means 106 records the reference measuring instrument judgment “pass”. (Step S111)
(8) The pass / fail judgment means 105 compares the value of the “maximum color difference with the average measured value” with a predetermined allowable value, makes a pass / fail judgment, and reports the judgment result. If the value of the “maximum color difference from the average measured value” is equal to or less than the allowable value, the result is passed and the process proceeds to (9). If the value of the “maximum color difference from the average measured value” exceeds the allowable value, the process proceeds to (10). (Step S112)
(9) The pass / fail judgment result recording means 106 records the average measurement value judgment “pass” and ends. (Step S113)
(10) The pass / fail determination result recording means 106 records the average measurement value determination “fail” and ends. (Step S114)
(11) The pass / fail judgment result recording means 106 records the reference measuring instrument judgment “fail”. (Step S121)
(12) The pass / fail determination means 105 compares the average measured value with the allowable value, determines pass / fail, and reports the determination result. If the average measured value is less than or equal to the allowable value, the test returns to (9). If the average measured value exceeds the allowable value, the process proceeds to (13). (Step S122)
(13) The pass / fail judgment result recording means 106 records the average measurement value judgment “fail”. (Step S123)
(14) The repair determination means 107 refers to the pass / fail determination result history file of the operation measuring instrument, and if the previous pass / fail determination result is “pass”, proceeds to (15). If it is “Fail”, proceed to (16). (Step S124)
(15) The repair judgment means 107 refers to the pass / fail judgment result history file of the operational measuring device, calculates the failure rate of this operational measuring device, and ends if it is less than the predetermined failure rate allowable value. . If it is greater than the specified acceptable rejection rate, proceed to (16). (Step S125)
(16) Report calibration or repair required and end. (Step S126)

FIG. 10 is an example of a measurement accuracy determination result list of the spectrophotometer. The items of the pass / fail judgment result are the same as those in FIG. The No. 1 spectrophotometer is a reference spectrophotometer, and the nine spectrophotometers from No. 2 spectrophotometer to No. 10 spectrophotometer are spectrophotometers that check measurement accuracy. Since the “maximum color difference from the reference value” from the No. 2 spectrophotometer to the No. 6 spectrophotometer is less than the allowable value 0.8, the “reference value judgment” is passed, and “go” 110w is recorded. Is done. Since the “maximum color difference from the reference value” from the No. 7 spectrophotometer to the No. 10 spectrophotometer is an allowable value of 0.8 or more, the “reference value judgment” is rejected, and “No” is 110x. To be recorded. Since the value of “maximum color difference from the average measured value” from the No. 2 spectrophotometer to the No. 7 spectrophotometer is less than the allowable value 0.8, the “average measured value judgment” is passed and the “total” 110y Is recorded. The “maximum color difference from the average measurement value” from the No. 8 spectrophotometer to the No. 10 spectrophotometer is an allowable value of 0.8 or more, so the “average measurement value judgment” is rejected and “No” 110z is recorded.

Therefore, as described in the flowchart of FIG. 9, the No. 2 spectrophotometer to the No. 7 spectrophotometer are determined to be “combined”, and it is determined that there is no problem in measurement accuracy. No. 8 spectrophotometers to No. 10 spectrophotometers were judged as “No”, and it was judged that there was a problem in measurement accuracy. Therefore, the necessity of calibration repair was judged with reference to the pass / fail judgment result history file 110a. Is done.

FIG. 11 is a pass / fail judgment result history file 110a of No. 8 spectrophotometer. Therefore, as described with reference to the flowchart of FIG. 9, when the pass / fail judgment result history file 110a of the No. 8 spectrophotometer is referred to, the previous (November 1) pass / fail judgment result indicates that the “reference value judgment” is “no”. Since 110s is recorded, it is determined that repair is necessary.

FIG. 12 is a pass / fail judgment result history file 110a of No. 9 spectrophotometer. Therefore, as described with reference to the flowchart of FIG. 9, when the pass / fail judgment result history file 110a of No. 9 spectrophotometer is referred to, the previous (November 1) pass / fail judgment result is “reference value judgment” 110s and “average”. Since both “measured value determination” 110t is recorded as “go” and the “failure rate 110h” for the past five “reference value determination” is “60%”, it is determined that repair is necessary.

FIG. 13 is a pass / fail judgment result history file 110a of the No. 10 spectrometer photometer. Accordingly, as described with reference to the flowchart of FIG. 9, when the pass / fail judgment result history file 110a of No. 10 spectrophotometer is referred to, the previous (November 1) pass / fail judgment result is the reference value judgment “110s” and “average measurement”. Both “value determination” 110t are recorded as “go”, and both the reference value determination failure rate 110h and the average measurement value determination failure rate 110i are both “20%”. , Determined to be unnecessary.

In this way, the standard sample used for pass / fail judgment must use the same standard sample in one accuracy check, but it is not necessary to use the same standard sample in other accuracy checks. This makes it easier to manage standard samples.

In the working examples, the measurement accuracy of the spectrophotometer has been described by a method using CIELab (L value, a value, b value) obtained by measuring the color chart of 80 colors, but the method is limited to this method. It is not something. Other measurement methods include the Munsell display system (JIS Z 8721 1983) and the BCRA tile (ceramic color standard plate commonly used to guarantee the accuracy of spectrophotometers. Certificate of calibration by the British Standardization Committee) Or any other method that uses a sample that can be stably measured with a spectrophotometer. Further, instead of the CIELab color difference used as the determination value, the square root of the square sum of the spectral reflectance difference depending on the measurement wavelength, CMC color difference, CIE94 color difference, CIE2000 color difference, or the like may be used.

As described above in detail, according to the present invention, an apparatus and a method for easily checking the accuracy of a measuring instrument can be provided.

Configuration diagram of measuring instrument quality control device Structure of measured value file Spectrophotometer color difference calculation formula (1) (color difference with reference value) Example of color difference graph of measuring instrument (1) (color difference with reference value) Spectrophotometer color difference calculation formula (2) (color difference from average measured value) Example of color difference graph of measuring device (2) (color difference from average measured value) Pass / fail result of spectrophotometer Example of spectrophotometer pass / fail result history (1) Flow chart of measuring instrument quality control device Example of spectrophotometer measurement accuracy judgment result list Example of a spectrophotometer pass / fail judgment result history file (2) (for No. 8 spectrophotometer) Example of spectrophotometer pass / fail judgment result history file (3) (for No. 9 spectrophotometer) Example of spectrophotometer pass / fail judgment result history file (4) (for No. 10 spectrophotometer)

Explanation of symbols

100 measuring instrument accuracy management device 101 measured value reading means 102 reference value selecting means 103 average value calculating means 104 judgment value calculating means 105 measurement accuracy pass / fail judgment means 106 measurement accuracy pass / fail judgment result recording means 107 repair judgment means 110 storage means 110a measurement accuracy Pass / fail judgment result history file 200 Measuring instrument 210 Storage means 201a Measurement value file 201b CIELab
201c Color chart number 201d L value 201e a value 201f b value 311 Formula 411 for determining CIELab color difference ΔE between the spectrophotometer for checking the measurement accuracy and the reference spectrophotometer 411 between the spectrophotometer and the reference spectrophotometer for checking the measurement accuracy Color difference graph 411a Maximum color difference 312 Spectral photometer for checking measurement accuracy and formula 412 for determining CIELab color difference ΔE _a of average value Color difference graph 412a for color difference graph of spectrophotometer for checking measurement accuracy and average measurement value

Claims (5)

The storage means stores a pass / fail judgment result history file for recording the judgment result,
A measurement value reading means for obtaining a measurement value measured by a measuring instrument;
Reference value selection means for selecting a first reference value from the acquired measurement value;
A reference value calculating means for calculating a second reference value from the acquired measurement value;
A determination value calculation means for determining a difference between the first reference value or the second reference value and the acquired measurement value;
The judgment value is compared with the given tolerance value, and if it is less than the tolerance value, it is judged as acceptable, and if it exceeds the tolerance value, it is judged as unacceptable, and the judgment result of acceptance / failure is reported. Pass / fail judgment means;
A pass / fail judgment result recording means for recording the pass / fail judgment result in the pass / fail judgment result history file;
Means for calculating a rejection rate with reference to the pass / fail judgment result history file;
If the calculated failure rate is equal to or greater than a given failure rate allowable value, repair determination means for instructing calibration repair; and
A measuring instrument quality control device comprising: The first reference value is a measured value measured by a reference measuring instrument,
The measuring instrument accuracy management device according to claim 1, wherein the second reference value is an average value of measured values of measuring instruments other than the reference measuring instrument. A measurement value reading step for obtaining a measurement value measured by the measuring instrument;
A reference value selection step of selecting a reference value from the acquired measurement values;
A reference value calculating step of calculating an average value by selecting a measured value from the acquired measured values;
A determination value calculation step for determining a difference between the reference value or the average value and the acquired measurement value;
The judgment value is compared with the given tolerance value, and if it is less than the tolerance value, it is judged as acceptable, and if it exceeds the tolerance value, it is judged as unacceptable, and the judgment result of acceptance / failure is reported. A pass / fail judgment step;
Referring to the pass / fail judgment result history file and calculating a rejection rate;
If the calculated failure rate is equal to or greater than a given failure rate tolerance, a repair determination step for instructing calibration repair; and
A measuring instrument quality control method characterized by comprising a procedure including: A computer program that causes a computer to operate as the measuring instrument accuracy management device according to claim 1 or 2 by being incorporated in the computer. A computer-readable recording medium on which the program according to claim 4 is recorded.

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