Some standard content:
National Metrology Technical Specification of the People's Republic of China JJF 1148—2006
Calibration Specification for Test Devices of Contact Lenses2006-05-23 issued
08-23 fog applied
Issued by the General Administration of Quality Supervision, Inspection and Quarantine JJF 1148—200G
Calibration Specification for Test Devicesof Contact Lenses
JJF 1148—2006
This specification was approved by the General Administration of Quality Supervision, Inspection and Quarantine on May 23, 2006, and came into effect on August 23, 2006.
Responsible unit:
Main drafting unit:
Participating drafting unit:
National Technical Committee for Optical Metrology
China National Institute of Metrology
Chongqing Yuanshi Technology Co., Ltd.
This specification is interpreted by the National Technical Committee for Optical Metrology Main drafter of this specification:
Zhang Jiyan
Participating drafter:
JJF 1148-2006
(China Institute of Metrology)
(National Institute of Metrology)
(Chongqing Yuanshi Technology Co., Ltd.)
References
3 Terminology
Contact lens diameter
Contact lens posterior optical zone curvature radius
Contact lens center thickness
3.4 Corneal contact lens tester
4 OverviewWww.bzxZ.net
Measurement principle
5 Halo characteristics
Diameter indication error
5.2 Posterior optical zone curvature radius indication error
5.3 Center thickness 5.4 Repeatability of measurement of radius of curvature of posterior optical zone 6 Calibration conditions 6.1 Environmental conditions 6.2 Calibration solution 6.3 Calibration standard 7 Calibration items and calibration methods 7.1 Preparations before calibration 7.2 Diameter indication error 7.3 Diameter indication error 7.4 Repeatability of measurement of radius of curvature of posterior optical zone 7.5 Center thickness indication error 8 Expression of calibration results 9 Recalibration time interval 7.5 Center thickness indication error 8.1 Calibration results 9 Recalibration time interval 1148-—2006
Uncertainty analysis of indication error of curvature radius of contact lens tester Appendix A
1 Scope
JJF1148—2006
Calibration specification for contact lens tester
This specification is applicable to the calibration of contact lens testers of various principles and categories that are specially used to measure geometric parameters such as diameter, posterior optical zone curvature radius, center thickness, etc. of soft hydrophilic contact lenses (hereinafter referred to as contact lenses).
2 References
ISO/FDIS18369-3:2005 "Ophthalmic optics - Contact lenses - Part 3: Measurement methods"
IS010344:1996 "Optics and optical instruments - Contact lenses - Saline solution for contact lens testing"
JF1059-1999 "Evaluation and expression of uncertainty in measurement" When using this specification, attention should be paid to the use of the current valid versions of the above-mentioned references. 3 Terminology
3.1 Contact lens diameter
The maximum outer dimension of the finished contact lens
3.2 Radius of curvature of the optical zone of the contact lens
The radius of curvature of the optical zone at the back of the contact lens. 3.3 Center thickness of the contact lens
The thickness of the contact lens at the center of the base.
3.4 Corneal contact lens tester
Instruments used to measure geometric parameters such as the diameter, radius of curvature and center thickness of contact lenses are generally called corneal contact lens testers (hereinafter referred to as contact lens testers). 4 Overview
4.1 Purpose
Contact lens testers are mainly used to measure geometric parameters such as contact lens diameter, curvature diameter of the optical zone behind the contact lens and center thickness of the contact lens. Some equipment can also be used to quickly observe the surface quality and defects of contact lenses. 4.2 Measurement principle
The contact lens testers widely used by domestic manufacturers at present generally have the function of measuring diameter, radius of curvature and center thickness. They are mostly used for the measurement of soft hydrophilic contact lenses. They are an instrument integrating optics, machinery and electricity. This type of instrument usually consists of two sets of measuring optical paths, which respectively realize different measurement functions. The measurement principle is shown in Figure 1. By controlling the position of the reflector (3), the switching of different measuring optical paths can be realized. The light beam passes through the measured sample pool (10), and the diameter of the contact lens can be measured. The light beam passes through the measured sample pool (4), and the radius of curvature of the optical zone behind the contact lens and the center thickness of the contact lens can be measured. SNOH ENIHST
1-light source: 2
Figure 3-rotatable reflector.
radius of curvature, center thickness measurement and sample pool 2, projection objective lens; 8
12-projection objective lens
preview mirror
diameter measurement sample
observation screen
light mirror:
report groove straight win, that is, the lens is selected to be tangent to both sides of the V-shaped groove,
contact lens is placed for diameter measurement,
the diameter of the lens to be measured is directly read from the √-shaped ruler. During the measurement process, the entire α is magnified and reflected by the top reflector (13) and projected onto the observation screen. At this time, the surface quality and defects of the lens can be directly observed. The high-precision ROL method is to move the probe so that it just touches the back surface vertex of the lens being measured, and then simply calculate to make it contact with the back surface vertex of the lens being measured, so as to measure the back optical zone curvature radius of the lens. The measurement of the center thickness of the contact lens is usually completed simultaneously when the back optical zone curvature radius is measured, that is; when the probe just touches the back surface vertex of the lens being measured, the front and back surface positions at the geometric center of the lens being measured are detected, and the center thickness of the lens being measured is obtained by calculating the difference between the two positions. Some contact lens testers project a scale onto the observation screen for magnification, and read it visually to obtain the measurement value of the center thickness. 5 Metrological characteristics
Diameter indication error
JJF 1148---2006
The diameter measurement range of the contact lens tester should meet (8～16)mm, and the diameter indication error is 笵0.05mms5.2 Indication error of the radius of curvature of the posterior optical zone
The measurement range of the radius of curvature of the contact lens tester should meet (6.5～9.5)mm, and the indication error of the radius of curvature of the posterior optical zone is ±U.05mmrmu
5.3 Indication error of center thickness
The measurement range of the center thickness of the contact lens tester should meet (01.0)mm, and the indication error of the center thickness is 10.005rina
The posterior optical zone h2 of the contact lens tester can be used
5.4 Measurement of the flat diameter of the curvature of the posterior optical zone is repeated
Note: Since the calibration does not determine the fall and drum, the above requirements are for reference only. A
6 Calibration conditions
Environmental conditions
Temperature: (23
6.2 Calibration solution
For contact lens measurement
; Relative humidity
6.3 Calibration
For contact lens measurement
, Calibration solution or physiological saline
6.3.1 Diameter
Diameter standard
15.00mm, with silicon degree reference. Three-piece plane scale
6.3.2. The calibration solution for the radius of curvature of the instrument is specified in ISO 10344. The special standard is made of optical glass material and consists of standard lenses with different thicknesses. The nominal values of the diameter of the standard are 10.00, 13.00 and 7.00 mm respectively. The nominal values of the radius of curvature of the optical zone of the three lenses are 5 and 900 mm respectively. They are used to calibrate the indication error and measurement repeatability of the radius of curvature of the optical zone of the instrument.
6.3.3 Center Thickness Standard Lens
The center thickness standard lens is composed of three spherical lenses with different center thicknesses. The nominal center thickness values are 0.20, 0.25 and 0.30 mm respectively. It is used to calibrate the center thickness indication error of the contact lens tester. 7 Calibration Items and Calibration Methods
7.1 Preparation before Calibration
Before using the above calibration standard pusher to calibrate the contact lens tester, first fill the sample pool with an appropriate amount of calibration solution, and then put different types of standard lenses in turn for calibration according to the following calibration items and contents.
7.2 Diameter Indication Error
JJF 1148—2006
According to the requirements of 5.1, use the diameter standard lens described in 6.3.1 to calibrate the diameter indication of the contact lens tester. Each standard lens is measured at least 5 times, and the average value is taken as the final measurement result, and compared with the standard value of the corresponding diameter standard lens. The difference is the error of the instrument at the measuring point. 7.3 Error of curvature diameter indication of the posterior optical zone
According to the requirements of 5.2, the curvature radius standard lens described in 6.3.2 is used to calibrate the curvature radius indication of the posterior optical zone of the contact lens tester. Each standard lens is measured at least 5 times, and the average value is taken as the final measurement result, and compared with the standard value of the corresponding curvature radius standard lens. The difference is the error of the curvature radius indication of the instrument at the measuring point.
7.4 Repeatability of measurement of flat diameter of curvature of posterior optical zone According to the requirements of 5.4, according to the calibration data of curvature radius of posterior optical zone obtained in 7.3, calculate the range of 5 measurements, that is, the difference between the maximum and minimum measurement values, and take the maximum value of the range in the curvature radius standard lens as the repeatability of the instrument's posterior optical zone curvature half-measurement. 7.5 Center thickness indication error
According to the requirements of 5.3, use the center thickness standard lens described in 6.3.3 to calibrate the center thickness indication of the contact lens measuring instrument. Repeat the measurement for each standard lens at least 5 times, take the average value as the final measurement result, and compare it with the standard value of the corresponding center thickness standard lens. The difference is the center thickness indication error of the instrument at the measuring point.
8 Expression of calibration results
The calibration results shall be reflected in the calibration certificate or calibration report, which shall include at least the following information:
a) Title, such as "Calibration Certificate" or "Calibration Report"; b) Name and address of the laboratory; c) Location where the calibration was performed (if the calibration was not performed in the laboratory); d) Unique identification of the certificate or report (such as product edition), page number and total number of pages; e) Name and address of the sender; f) Description and clear identification of the object being calibrated; f) Date of calibration, if relevant to the validity and application of the calibration results, the date of receipt of the object being calibrated should be stated; h) If relevant to the validity and application of the calibration results, the date of receipt of the object being calibrated should be stated; Where relevant, the sampling procedure should be explained:) Identification of the technical specification on which the calibration is based, including name and code;) Traceability and validity of the measurement standard used in this calibration; k) Description of the calibration environment;
1) Explanation of the calibration results and their measurement uncertainty: JIF11482006
) The calibration certificate should indicate whether the various indicators meet the metrological performance requirements or general technical requirements: n) The calibration certificate should indicate the measurement object and measurement range limit of the calibrated instrument: o) The signature, position or equivalent identification, and issue date of the issuer of the calibration certificate or calibration report: P statement that the calibration result is valid for this calibration of the calibrated object: 9) Statement that the certificate or report shall not be partially reproduced without the written approval of the laboratory. The evaluation and expression of measurement uncertainty should generally comply with [F1059-1999 "Requirements for the evaluation and expression of measurement uncertainty", including the sources of uncertainty and its classification, formulas and expressions of uncertainty synthesis, etc. (Appendix A gives a specific example of uncertainty analysis). Recalibration time interval
The recalibration time interval can be determined by the user, and it is recommended not to exceed 1 year. Appendix A
JJF1148--2006
Uncertainty analysis of the indication error of the curvature radius of the contact lens detector Here, only the LJY-1 type corneal contact lens detector produced by a certain company is used as an example to analyze the uncertainty of the calibration result of the indication error of the curvature major axis.
A.1 Establishment of mathematical model
Using the functional radius standard lens to calibrate the curvature radius indication of the corneal contact lens detector, the following mathematical model can be established:
C=r-rn
Wu ZhongC——Minimum error:
—Average value of the measurement result;
r. —-Standard value of the curvature radius standard lens. A.2 Source of uncertainty
According to the above mathematical model, its sources of uncertainty mainly include the following aspects: a) Standard uncertainty ut introduced by the repeatability of the measurement of the radius of curvature; b) Standard uncertainty introduced by the standard lens of the radius of curvature; 2) Influence of ambient temperature: Under the normal use environment of the instrument, the characteristics of the standard lens are affected by temperature and change very little, so this item can be ignored. A.3 Uncertainty evaluation
A.3.1 Class A evaluation
1 is the standard uncertainty introduced by the measurement repeatability, which mainly comes from the error of the operator's judgment of the maximum measurement position. In the calibration of the indication error of the radius of curvature, the standard lens of the radius of curvature was measured 5 times respectively, among which the range of the 5 radius of curvature measurement values of the standard lens with a nominal value of 7.95mtn was the largest, and the data is shown in Table A.1. Table A.1
- 7.903 mm
Range R
Given that the standard value of the radius of curvature of the standard lens is r=7.946mm, the indication error is: - r-ru - -0.043 rm
Because repeatability is indicated by the range, d can be found from the range table. =2.33, so: A.3.2 Class B assessment
JJF 1148---2006
5d-5×2.33
0.004 5 mrm
u2 is the standard uncertainty introduced by the lens of the curvature radius. From the proof, we can know that its expanded uncertainty is 0.01 rm (=2), that is:
A.3.3 Synthetic standard uncertainty
= 0.005 mm
The above components are independent, so the synthetic standard uncertainty of the indication error of the curvature radius is =u +u2=V0.004 52 +0.005= 0.007mm A.3.4 Expanded uncertainty
The expanded uncertainty U is equal to the product of the coverage factor and the synthetic standard uncertainty. U=ku.=2×0.007=0.014mm
A.4 Report results
Based on the calculation and analysis of the above measurement results, it can be seen that the calibration results of the curvature radius of the corneal contact lens detector are as follows:
Minimum error: C=0.043 mm
Expanded uncertainty: U=0.014mm (=2). The uncertainty analysis of other calibration items of the corneal contact lens detector can be carried out in accordance with the above method and will not be repeated here.3 Center Thickness Standard Lens
The center thickness standard lens is composed of three spherical lenses with different center thicknesses. The nominal center thickness values are 0.20, 0.25 and 0.30 mm respectively. It is used to calibrate the center thickness indication error of the contact lens tester. 7 Calibration Items and Calibration Methods
7.1 Preparation before calibration
Before using the above calibration standard pusher to calibrate the contact lens tester, first fill the sample pool with an appropriate amount of calibration solution, and then put different types of standard lenses in turn for calibration according to the following calibration items and contents.
7.2 Diameter indication error
JJF 1148—2006
According to the requirements of 5.1, use the diameter standard lens described in 6.3.1 to calibrate the diameter indication of the contact lens tester. Each standard lens is measured at least 5 times, and the average value is taken as the final measurement result, and compared with the standard value of the corresponding diameter standard lens. The difference is the error of the instrument at the measuring point. 7.3 Error of curvature diameter indication of the posterior optical zone
According to the requirements of 5.2, the curvature radius standard lens described in 6.3.2 is used to calibrate the curvature radius indication of the posterior optical zone of the contact lens tester. Each standard lens is measured at least 5 times, and the average value is taken as the final measurement result, and compared with the standard value of the corresponding curvature radius standard lens. The difference is the error of the curvature radius indication of the instrument at the measuring point.
7.4 Repeatability of measurement of flat diameter of curvature of posterior optical zone According to the requirements of 5.4, according to the calibration data of curvature radius of posterior optical zone obtained in 7.3, calculate the range of 5 measurements, that is, the difference between the maximum and minimum measurement values, and take the maximum value of the range in the curvature radius standard lens as the repeatability of the instrument's posterior optical zone curvature half-measurement. 7.5 Center thickness indication error
According to the requirements of 5.3, use the center thickness standard lens described in 6.3.3 to calibrate the center thickness indication of the contact lens measuring instrument. Repeat the measurement for each standard lens at least 5 times, take the average value as the final measurement result, and compare it with the standard value of the corresponding center thickness standard lens. The difference is the center thickness indication error of the instrument at the measuring point.
8 Expression of calibration results
The calibration results shall be reflected in the calibration certificate or calibration report, which shall include at least the following information:
a) Title, such as "Calibration Certificate" or "Calibration Report"; b) Name and address of the laboratory; c) Location where the calibration was performed (if the calibration was not performed in the laboratory); d) Unique identification of the certificate or report (such as product edition), page number and total number of pages; e) Name and address of the sender; f) Description and clear identification of the object being calibrated; f) Date of calibration, if relevant to the validity and application of the calibration results, the date of receipt of the object being calibrated should be stated; h) If relevant to the validity and application of the calibration results, the date of receipt of the object being calibrated should be stated; Where relevant, the sampling procedure should be explained:) Identification of the technical specification on which the calibration is based, including name and code;) Traceability and validity of the measurement standard used in this calibration; k) Description of the calibration environment;
1) Explanation of the calibration results and their measurement uncertainty: JIF11482006
) The calibration certificate should indicate whether the various indicators meet the metrological performance requirements or general technical requirements: n) The calibration certificate should indicate the measurement object and measurement range limit of the calibrated instrument: o) The signature, position or equivalent identification, and issue date of the issuer of the calibration certificate or calibration report: P statement that the calibration result is valid for this calibration of the calibrated object: 9) Statement that the certificate or report shall not be partially reproduced without the written approval of the laboratory. The evaluation and expression of measurement uncertainty should generally comply with [F1059-1999 "Requirements for the evaluation and expression of measurement uncertainty", including the sources of uncertainty and its classification, formulas and expressions of uncertainty synthesis, etc. (Appendix A gives a specific example of uncertainty analysis). Recalibration time interval
The recalibration time interval can be determined by the user, and it is recommended not to exceed 1 year. Appendix A
JJF1148--2006
Uncertainty analysis of the indication error of the curvature radius of the contact lens detector Here, only the LJY-1 type corneal contact lens detector produced by a certain company is used as an example to analyze the uncertainty of the calibration result of the indication error of the curvature major axis.
A.1 Establishment of mathematical model
Using the functional radius standard lens to calibrate the curvature radius indication of the corneal contact lens detector, the following mathematical model can be established:
C=r-rn
Wu ZhongC——Minimum error:
—Average value of the measurement result;
r. —-Standard value of the curvature radius standard lens. A.2 Source of uncertainty
According to the above mathematical model, its sources of uncertainty mainly include the following aspects: a) Standard uncertainty ut introduced by the repeatability of the measurement of the radius of curvature; b) Standard uncertainty introduced by the standard lens of the radius of curvature; 2) Influence of ambient temperature: Under the normal use environment of the instrument, the characteristics of the standard lens are affected by temperature and change very little, so this item can be ignored. A.3 Uncertainty evaluation
A.3.1 Class A evaluation
1 is the standard uncertainty introduced by the measurement repeatability, which mainly comes from the error of the operator's judgment of the maximum measurement position. In the calibration of the indication error of the radius of curvature, the standard lens of the radius of curvature was measured 5 times respectively, among which the range of the 5 radius of curvature measurement values of the standard lens with a nominal value of 7.95mtn was the largest, and the data is shown in Table A.1. Table A.1
- 7.903 mm
Range R
Given that the standard value of the radius of curvature of the standard lens is r=7.946mm, the indication error is: - r-ru - -0.043 rm
Because repeatability is indicated by the range, d can be found from the range table. =2.33, so: A.3.2 Class B assessment
JJF 1148---2006
5d-5×2.33
0.004 5 mrm
u2 is the standard uncertainty introduced by the lens of the curvature radius. From the proof, we can know that its expanded uncertainty is 0.01 rm (=2), that is:
A.3.3 Synthetic standard uncertainty
= 0.005 mm
The above components are independent, so the synthetic standard uncertainty of the indication error of the curvature radius is =u +u2=V0.004 52 +0.005= 0.007mm A.3.4 Expanded uncertainty
The expanded uncertainty U is equal to the product of the coverage factor and the synthetic standard uncertainty. U=ku.=2×0.007=0.014mm
A.4 Report results
Based on the calculation and analysis of the above measurement results, it can be seen that the calibration results of the curvature radius of the corneal contact lens detector are as follows:
Minimum error: C=0.043 mm
Expanded uncertainty: U=0.014mm (=2). The uncertainty analysis of other calibration items of the corneal contact lens detector can be carried out in accordance with the above method and will not be repeated here.3 Center Thickness Standard Lens
The center thickness standard lens is composed of three spherical lenses with different center thicknesses. The nominal center thickness values are 0.20, 0.25 and 0.30 mm respectively. It is used to calibrate the center thickness indication error of the contact lens tester. 7 Calibration Items and Calibration Methods
7.1 Preparation before calibration
Before using the above calibration standard pusher to calibrate the contact lens tester, first fill the sample pool with an appropriate amount of calibration solution, and then put different types of standard lenses in turn for calibration according to the following calibration items and contents.
7.2 Diameter indication error
JJF 1148—2006
According to the requirements of 5.1, use the diameter standard lens described in 6.3.1 to calibrate the diameter indication of the contact lens tester. Each standard lens is measured at least 5 times, and the average value is taken as the final measurement result, and compared with the standard value of the corresponding diameter standard lens. The difference is the error of the instrument at the measuring point. 7.3 Error of curvature diameter indication of the posterior optical zone
According to the requirements of 5.2, the curvature radius standard lens described in 6.3.2 is used to calibrate the curvature radius indication of the posterior optical zone of the contact lens tester. Each standard lens is measured at least 5 times, and the average value is taken as the final measurement result, and compared with the standard value of the corresponding curvature radius standard lens. The difference is the error of the curvature radius indication of the instrument at the measuring point.
7.4 Repeatability of measurement of flat diameter of curvature of posterior optical zone According to the requirements of 5.4, according to the calibration data of curvature radius of posterior optical zone obtained in 7.3, calculate the range of 5 measurements, that is, the difference between the maximum and minimum measurement values, and take the maximum value of the range in the curvature radius standard lens as the repeatability of the instrument's posterior optical zone curvature half-measurement. 7.5 Center thickness indication error
According to the requirements of 5.3, use the center thickness standard lens described in 6.3.3 to calibrate the center thickness indication of the contact lens measuring instrument. Repeat the measurement for each standard lens at least 5 times, take the average value as the final measurement result, and compare it with the standard value of the corresponding center thickness standard lens. The difference is the center thickness indication error of the instrument at the measuring point.
8 Expression of calibration results
The calibration results shall be reflected in the calibration certificate or calibration report, which shall include at least the following information:
a) Title, such as "Calibration Certificate" or "Calibration Report"; b) Name and address of the laboratory; c) Location where the calibration was performed (if the calibration was not performed in the laboratory); d) Unique identification of the certificate or report (such as product edition), page number and total number of pages; e) Name and address of the sender; f) Description and clear identification of the object being calibrated; f) Date of calibration, if relevant to the validity and application of the calibration results, the date of receipt of the object being calibrated should be stated; h) If relevant to the validity and application of the calibration results, the date of receipt of the object being calibrated should be stated; Where relevant, the sampling procedure should be explained:) Identification of the technical specification on which the calibration is based, including name and code;) Traceability and validity of the measurement standard used in this calibration; k) Description of the calibration environment;
1) Explanation of the calibration results and their measurement uncertainty: JIF11482006
) The calibration certificate should indicate whether the various indicators meet the metrological performance requirements or general technical requirements: n) The calibration certificate should indicate the measurement object and measurement range limit of the calibrated instrument: o) The signature, position or equivalent identification, and issue date of the issuer of the calibration certificate or calibration report: P statement that the calibration result is valid for this calibration of the calibrated object: 9) Statement that the certificate or report shall not be partially reproduced without the written approval of the laboratory. The evaluation and expression of measurement uncertainty should generally comply with [F1059-1999 "Requirements for the evaluation and expression of measurement uncertainty", including the sources of uncertainty and its classification, formulas and expressions of uncertainty synthesis, etc. (Appendix A gives a specific example of uncertainty analysis). Recalibration time interval
The recalibration time interval can be determined by the user, and it is recommended not to exceed 1 year. Appendix A
JJF1148--2006
Uncertainty analysis of the indication error of the curvature radius of the contact lens detector Here, only the LJY-1 type corneal contact lens detector produced by a certain company is used as an example to analyze the uncertainty of the calibration result of the indication error of the curvature major axis.
A.1 Establishment of mathematical model
Using the functional radius standard lens to calibrate the curvature radius indication of the corneal contact lens detector, the following mathematical model can be established:
C=r-rn
Wu ZhongC——Minimum error:
—Average value of the measurement result;
r. —-Standard value of the curvature radius standard lens. A.2 Source of uncertainty
According to the above mathematical model, its sources of uncertainty mainly include the following aspects: a) Standard uncertainty ut introduced by the repeatability of the measurement of the radius of curvature; b) Standard uncertainty introduced by the standard lens of the radius of curvature; 2) Influence of ambient temperature: Under the normal use environment of the instrument, the characteristics of the standard lens are affected by temperature and change very little, so this item can be ignored. A.3 Uncertainty evaluation
A.3.1 Class A evaluation
1 is the standard uncertainty introduced by the measurement repeatability, which mainly comes from the error of the operator's judgment of the maximum measurement position. In the calibration of the indication error of the radius of curvature, the standard lens of the radius of curvature was measured 5 times respectively, among which the range of the 5 radius of curvature measurement values of the standard lens with a nominal value of 7.95mtn was the largest, and the data is shown in Table A.1. Table A.1
- 7.903 mm
Range R
Given that the standard value of the radius of curvature of the standard lens is r=7.946mm, the indication error is: - r-ru - -0.043 rm
Because repeatability is indicated by the range, d can be found from the range table. =2.33, so: A.3.2 Class B assessment
JJF 1148---2006
5d-5×2.33
0.004 5 mrm
u2 is the standard uncertainty introduced by the lens of the curvature radius. From the proof, we can know that its expanded uncertainty is 0.01 rm (=2), that is:
A.3.3 Synthetic standard uncertainty
= 0.005 mm
The above components are independent, so the synthetic standard uncertainty of the indication error of the curvature radius is =u +u2=V0.004 52 +0.005= 0.007mm A.3.4 Expanded uncertainty
The expanded uncertainty U is equal to the product of the coverage factor and the synthetic standard uncertainty. U=ku.=2×0.007=0.014mm
A.4 Report results
Based on the calculation and analysis of the above measurement results, it can be seen that the calibration results of the curvature radius of the corneal contact lens detector are as follows:
Minimum error: C=0.043 mm
Expanded uncertainty: U=0.014mm (=2). The uncertainty analysis of other calibration items of the corneal contact lens detector can be carried out in accordance with the above method and will not be repeated here.3, calculate the range of the five measured values, that is, the difference between the maximum and minimum measured values, and take the maximum value of the range in the standard lens of the radius of curvature as the repeatability of the instrument's half-measurement of the curvature of the posterior optical zone. 7.5 Center thickness indication error
According to the requirements of 5.3, use the center thickness standard lens described in 6.3.3 to calibrate the center thickness indication of the contact lens tester. Repeat the measurement of each standard lens at least 5 times, take the average value as the final measurement result, and compare it with the standard value of the corresponding center thickness standard lens. The difference is the center thickness indication error of the instrument at the measuring point.
8 Expression of calibration results
The calibration results shall be reflected in the calibration certificate or calibration report, which shall include at least the following information:
a) Title, such as "Calibration Certificate" or "Calibration Report"; b) Name and address of the laboratory; c) Location where the calibration was performed (if the calibration was not performed in the laboratory); d) Unique identification of the certificate or report (such as product edition), page number and total number of pages; e) Name and address of the sender; f) Description and clear identification of the object being calibrated; f) Date of calibration, if relevant to the validity and application of the calibration results, the date of receipt of the object being calibrated should be stated; h) If relevant to the validity and application of the calibration results, the date of receipt of the object being calibrated should be stated; Where relevant, the sampling procedure should be explained:) Identification of the technical specification on which the calibration is based, including name and code;) Traceability and validity of the measurement standard used in this calibration; k) Description of the calibration environment;
1) Explanation of the calibration results and their measurement uncertainty: JIF11482006
) The calibration certificate should indicate whether the various indicators meet the metrological performance requirements or general technical requirements: n) The calibration certificate should indicate the measurement object and measurement range limit of the calibrated instrument: o) The signature, position or equivalent identification, and issue date of the issuer of the calibration certificate or calibration report: P statement that the calibration result is valid for this calibration of the calibrated object: 9) Statement that the certificate or report shall not be partially reproduced without the written approval of the laboratory. The evaluation and expression of measurement uncertainty should generally comply with [F1059-1999 "Requirements for the evaluation and expression of measurement uncertainty", including the sources of uncertainty and its classification, formulas and expressions of uncertainty synthesis, etc. (Appendix A gives a specific example of uncertainty analysis). Recalibration time interval
The recalibration time interval can be determined by the user, and it is recommended not to exceed 1 year. Appendix A
JJF1148--2006
Uncertainty analysis of the indication error of the curvature radius of the contact lens detector Here, only the LJY-1 type corneal contact lens detector produced by a certain company is used as an example to analyze the uncertainty of the calibration result of the indication error of the curvature major axis.
A.1 Establishment of mathematical model
Using the functional radius standard lens to calibrate the curvature radius indication of the corneal contact lens detector, the following mathematical model can be established:
C=r-rn
Wu ZhongC——Minimum error:
—Average value of the measurement result;
r. —-Standard value of the curvature radius standard lens. A.2 Source of uncertainty
According to the above mathematical model, its sources of uncertainty mainly include the following aspects: a) Standard uncertainty ut introduced by the repeatability of the measurement of the radius of curvature; b) Standard uncertainty introduced by the standard lens of the radius of curvature; 2) Influence of ambient temperature: Under the normal use environment of the instrument, the characteristics of the standard lens are affected by temperature and change very little, so this item can be ignored. A.3 Uncertainty evaluation
A.3.1 Class A evaluation
1 is the standard uncertainty introduced by the measurement repeatability, which mainly comes from the error of the operator's judgment of the maximum measurement position. In the calibration of the indication error of the radius of curvature, the standard lens of the radius of curvature was measured 5 times respectively, among which the range of the 5 radius of curvature measurement values of the standard lens with a nominal value of 7.95mtn was the largest, and the data is shown in Table A.1. Table A.1
- 7.903 mm
Range R
Given that the standard value of the radius of curvature of the standard lens is r=7.946mm, the indication error is: - r-ru - -0.043 rm
Because repeatability is indicated by the range, d can be found from the range table. =2.33, so: A.3.2 Class B assessment
JJF 1148---2006
5d-5×2.33
0.004 5 mrm
u2 is the standard uncertainty introduced by the lens of the curvature radius. From the proof, we can know that its expanded uncertainty is 0.01 rm (=2), that is:
A.3.3 Synthetic standard uncertainty
= 0.005 mm
The above components are independent, so the synthetic standard uncertainty of the indication error of the curvature radius is =u +u2=V0.004 52 +0.005= 0.007mm A.3.4 Expanded uncertainty
The expanded uncertainty U is equal to the product of the coverage factor and the synthetic standard uncertainty. U=ku.=2×0.007=0.014mm
A.4 Report results
Based on the calculation and analysis of the above measurement results, it can be seen that the calibration results of the curvature radius of the corneal contact lens detector are as follows:
Minimum error: C=0.043 mm
Expanded uncertainty: U=0.014mm (=2). The uncertainty analysis of other calibration items of the corneal contact lens detector can be carried out in accordance with the above method and will not be repeated here.3, calculate the range of the five measured values, that is, the difference between the maximum and minimum measured values, and take the maximum value of the range in the standard lens of the radius of curvature as the repeatability of the instrument's half-measurement of the curvature of the posterior optical zone. 7.5 Center thickness indication error
According to the requirements of 5.3, use the center thickness standard lens described in 6.3.3 to calibrate the center thickness indication of the contact lens tester. Repeat the measurement of each standard lens at least 5 times, take the average value as the final measurement result, and compare it with the standard value of the corresponding center thickness standard lens. The difference is the center thickness indication error of the instrument at the measuring point.
8 Expression of calibration results
The calibration results shall be reflected in the calibration certificate or calibration report, which shall include at least the following information:
a) Title, such as "Calibration Certificate" or "Calibration Report"; b) Name and address of the laboratory; c) Location where the calibration was performed (if the calibration was not performed in the laboratory); d) Unique identification of the certificate or report (such as product edition), page number and total number of pages; e) Name and address of the sender; f) Description and clear identification of the object being calibrated; f) Date of calibration, if relevant to the validity and application of the calibration results, the date of receipt of the object being calibrated should be stated; h) If relevant to the validity and application of the calibration results, the date of receipt of the object being calibrated should be stated; Where relevant, the sampling procedure should be explained:) Identification of the technical specification on which the calibration is based, including name and code;) Traceability and validity of the measurement standard used in this calibration; k) Description of the calibration environment;
1) Explanation of the calibration results and their measurement uncertainty: JIF11482006
) The calibration certificate should indicate whether the various indicators meet the metrological performance requirements or general technical requirements: n) The calibration certificate should indicate the measurement object and measurement range limit of the calibrated instrument: o) The signature, position or equivalent identification, and issue date of the issuer of the calibration certificate or calibration report: P statement that the calibration result is valid for this calibration of the calibrated object: 9) Statement that the certificate or report shall not be partially reproduced without the written approval of the laboratory. The evaluation and expression of measurement uncertainty should generally comply with [F1059-1999 "Requirements for the evaluation and expression of measurement uncertainty", including the sources of uncertainty and its classification, formulas and expressions of uncertainty synthesis, etc. (Appendix A gives a specific example of uncertainty analysis). Recalibration time interval
The recalibration time interval can be determined by the user, and it is recommended not to exceed 1 year. Appendix A
JJF1148--2006
Uncertainty analysis of the indication error of the curvature radius of the contact lens detector Here, only the LJY-1 type corneal contact lens detector produced by a certain company is used as an example to analyze the uncertainty of the calibration result of the indication error of the curvature major axis.
A.1 Establishment of mathematical model
Using the functional radius standard lens to calibrate the curvature radius indication of the corneal contact lens detector, the following mathematical model can be established:
C=r-rn
Wu ZhongC——Minimum error:
—Average value of the measurement result;
r. —-Standard value of the curvature radius standard lens. A.2 Source of uncertainty
According to the above mathematical model, its sources of uncertainty mainly include the following aspects: a) Standard uncertainty ut introduced by the repeatability of the measurement of the radius of curvature; b) Standard uncertainty introduced by the standard lens of the radius of curvature; 2) Influence of ambient temperature: Under the normal use environment of the instrument, the characteristics of the standard lens are affected by temperature and change very little, so this item can be ignored. A.3 Uncertainty evaluation
A.3.1 Class A evaluation
1 is the standard uncertainty introduced by the measurement repeatability, which mainly comes from the error of the operator's judgment of the maximum measurement position. In the calibration of the indication error of the radius of curvature, the standard lens of the radius of curvature was measured 5 times respectively, among which the range of the 5 radius of curvature measurement values of the standard lens with a nominal value of 7.95mtn was the largest, and the data is shown in Table A.1. Table A.1
- 7.903 mm
Range R
Given that the standard value of the radius of curvature of the standard lens is r=7.946mm, the indication error is: - r-ru - -0.043 rm
Because repeatability is indicated by the range, d can be found from the range table. =2.33, so: A.3.2 Class B assessment
JJF 1148---2006
5d-5×2.33
0.004 5 mrm
u2 is the standard uncertainty introduced by the lens of the curvature radius. From the proof, we can know that its expanded uncertainty is 0.01 rm (=2), that is:
A.3.3 Synthetic standard uncertainty
= 0.005 mm
The above components are independent, so the synthetic standard uncertainty of the indication error of the curvature radius is =u +u2=V0.004 52 +0.005= 0.007mm A.3.4 Expanded uncertainty
The expanded uncertainty U is equal to the product of the coverage factor and the synthetic standard uncertainty. U=ku.=2×0.007=0.014mm
A.4 Report results
Based on the calculation and analysis of the above measurement results, it can be seen that the calibration results of the curvature radius of the corneal contact lens detector are as follows:
Minimum error: C=0.043 mm
Expanded uncertainty: U=0.014mm (=2). The uncertainty analysis of other calibration items of the corneal contact lens detector can be carried out in accordance with the above method and will not be repeated here.2 Sources of uncertainty
According to the above mathematical model, its sources of uncertainty mainly include the following aspects: a) Standard uncertainty ut introduced by the repeatability of the measurement of the radius of curvature; b) Standard uncertainty introduced by the standard lens of the radius of curvature; 2) Influence of ambient temperature: Under the normal use environment of the instrument, the characteristics of the standard lens are affected by temperature and change very little, so this item can be ignored. A.3 Uncertainty evaluation
A.3.1 Class A evaluation
1 is the standard uncertainty introduced by the measurement repeatability, which mainly comes from the error of the operator's judgment of the maximum measurement position. In the calibration of the indication error of the radius of curvature, the standard lens of the radius of curvature was measured 5 times respectively, among which the range of the 5 radius of curvature measurement values of the standard lens with a nominal value of 7.95mtn was the largest, and the data is shown in Table A.1. Table A.1
- 7.903 mm
Range R
Given that the standard value of the radius of curvature of the standard lens is r=7.946mm, the indication error is: - r-ru - -0.043 rm
Because repeatability is indicated by the range, d can be found from the range table. =2.33, so: A.3.2 Class B assessment
JJF 1148---2006
5d-5×2.33
0.004 5 mrm
u2 is the standard uncertainty introduced by the lens of the curvature radius. From the proof, we can know that its expanded uncertainty is 0.01 rm (=2), that is:
A.3.3 Synthetic standard uncertainty
= 0.005 mm
The above components are independent, so the synthetic standard uncertainty of the indication error of the curvature radius is =u +u2=V0.004 52 +0.005= 0.007mm A.3.4 Expanded uncertainty
The expanded uncertainty U is equal to the product of the coverage factor and the synthetic standard uncertainty. U=ku.=2×0.007=0.014mm
A.4 Report results
Based on the calculation and analysis of the above measurement results, it can be seen that the calibration results of the curvature radius of the corneal contact lens detector are as follows:
Minimum error: C=0.043 mm
Expanded uncertainty: U=0.014mm (=2). The uncertainty analysis of other calibration items of the corneal contact lens detector can be carried out in accordance with the above method and will not be repeated here.2 Sources of uncertainty
According to the above mathematical model, its sources of uncertainty mainly include the following aspects: a) Standard uncertainty ut introduced by the repeatability of the measurement of the radius of curvature; b) Standard uncertainty introduced by the standard lens of the radius of curvature; 2) Influence of ambient temperature: Under the normal use environment of the instrument, the characteristics of the standard lens are affected by temperature and change very little, so this item can be ignored. A.3 Uncertainty evaluation
A.3.1 Class A evaluation
1 is the standard uncertainty introduced by the measurement repeatability, which mainly comes from the error of the operator's judgment of the maximum measurement position. In the calibration of the indication error of the radius of curvature, the standard lens of the radius of curvature was measured 5 times respectively, among which the range of the 5 radius of curvature measurement values of the standard lens with a nominal value of 7.95mtn was the largest, and the data is shown in Table A.1. Table A.1
- 7.903 mm
Range R
Given that the standard value of the radius of curvature of the standard lens is r=7.946mm, the indication error is: - r-ru - -0.043 rm
Because repeatability is indicated by the range, d can be found from the range table. =2.33, so: A.3.2 Class B assessment
JJF 1148---2006
5d-5×2.33
0.004 5 mrm
u2 is the standard uncertainty introduced by the lens of the curvature radius. From the proof, we can know that its expanded uncertainty is 0.01 rm (=2), that is:
A.3.3 Synthetic standard uncertainty
= 0.005 mm
The above components are independent, so the synthetic standard uncertainty of the indication error of the curvature radius is =u +u2=V0.004 52 +0.005= 0.007mm A.3.4 Expanded uncertainty
The expanded uncertainty U is equal to the product of the coverage factor and the synthetic standard uncertainty. U=ku.=2×0.007=0.014mm
A.4 Report results
Based on the calculation and analysis of the above measurement results, it can be seen that the calibration results of the curvature radius of the corneal contact lens detector are as follows:
Minimum error: C=0.043 mm
Expanded uncertainty: U=0.014mm (=2). The uncertainty analysis of other calibration items of the corneal contact lens detector can be carried out in accordance with the above method and will not be repeated here.
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