In our daily vision measurement and image measurement, we often encounter some measurement terms. Today, we collect some professional terms in measurement to introduce them in detail.

1. Measurement: An operation to determine a value.

2. Measured value: the value obtained directly from the measuring instrument or through necessary calculation.

3. Accuracy of measurement: the degree of consistency between the measured results and the agreed true values of the measured values.

4. Repeatability of measurements: Under the following conditions, continuous measurements of the same measurements are made, and the consistency between the measurements is achieved.

Including: the same measurement method; the same observer; the same measurement instrument; the same location; the same conditions of use; repeated in a short time interval.

5. Reproducibility of measurements: Change one or more of the following conditions to continuously measure the same measurements, and the degree of consistency between the measurements.

Including: measurement methods, observers, measuring instruments, location, use conditions, time and so on.

6. Uncertainty of measurement: the evaluation of the range of the measured true value.

7. Absolute error of measurement: the difference between the measured result and the agreed true value of the measured value.

8. Relative error: the ratio of the absolute error of measurement to the true value of measurement.

9. Random error: The component of measurement error that varies unknowingly in the course of multiple measurements of the same measurement.

10. Systematic error: The component of measurement error that remains constant or varies in a predictable manner during multiple measurements of the same measurement.

11. Personnel errors: errors caused by subjective factors and operation techniques of surveyors.

12. Environmental Error: The component of measurement error that can vary with the environment.

13. Method Error: Error caused by imperfect measurement method.

14. Adjustment error: The error caused by the failure to adjust the measuring instrument or object to the correct position or state.

15. Reading errors: errors caused by inaccurate reading of measuring instruments by observers.

Parallax: Errors caused by the observer's deviation from the correct direction of observation in reading or aiming.

17. Estimation error: The error caused by the estimation within the range of the grading value.

18. Gross error: Obviously exceeding the expected error under specified conditions.

19. Measuring force: The measuring pressure exerted by the measuring instrument on the measured surface (position) of the measured part.

20. Measuring Instruments: Instruments that can be used separately or together with other devices to determine geometric quantities.