engleski

CALIBRATION OF LINE SCALES AT LFSB

Calibration of the line scales at the level of measurement uncertainties of the order of value U=0, 1μ m, k=2 represents today still a world problem, although these levels of measurement uncertainties are necessary in the context of ensuring the traceability. The greatest drawback of the measurement methods for the calibration of the line scales is the influence (subjectivity) of the measurer in the procedure of sighting the line scale, regardless of the use of technical aids (microscope, cameras, etc.). So, the Laboratory for precise measurement of length (LFSB) at Faculty of Mechanical Engineering and Naval Architecture in Zagreb started to design their own optoelectronic system for the calibration of line scales. The paper presents main characteristics of the device for calibration of line scales, software for sighting of lines, influences on measurement uncertainties and our measuring results of calibration NPL line scale which is also calibrated at PTB. Special attention in the paper will be given in a study of the scale and laser measuring system alignment. Also, the paper presents influences of the pitch and yaw errors of the table and the elastic table deformations on the calibration results.

length; calibration; line scale

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