If the user measures at different energy levels than the calibration energy level, the maximum error is the published linearity limit, usually ±2% This linearity is determined by varying the energy at a given pulse rate and measuring the output versus an average power reading on a. If the user measures at different energy levels than the calibration energy level, the maximum error is the published linearity limit, usually ±2% This linearity is determined by varying the energy at a given pulse rate and measuring the output versus an average power reading on a. EXFO can help save both time and costs with an automated calibration test system that is designed for the verification of power meters, attenuators, sources and optical time-domain reflectometers (OTDRs). This application note demystifies how EXFO's IQS-12002 Optical Calibration System can guide. Often, users assume that the rated calibration uncertainty of the Newport detector or power meter is the only error in their measurements, however, other factors also contribute to measurement uncertainty. Total measurement error is the sum of all possible sources of error, with detector or meter. This document discusses the interpretation and basis for stated measurement accuracy of Ophir Laser Power/Energy meters. To address the inherent characterize these instruments.