Giannis_TDM
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- Apr 27, 2019
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No they are not, proper LPMs (past the prehistoric units of the 90s) get calibrated like this: First the monitor(where your numbers are displayed) is electrically calibrated cause it is essentially a micro/nanovolt meter on the low ranges then the head gets calibrated with a NIST traceable source for the power measurement at the source's wavelength(Usually 1064nm), After that the head is run through a spectrophotometer to characterize the spectral response of the coating in that specific sensor cause even the response of the coating can vary between heads of the same model. Using the spectral responce chart you have now obtained you can create per WL correction factors for every WL your spectrophotometer is able to produce/measure.I would think that if you are going to calibrate your LPM this way, you need only use the resistor temporarily. LPMs are usually calibrated using a single wavelength laser and that wavelength depends on what you intend on measuring with it. Many are calibrated using an IR laser, but it really depends on what you are going to measure.