How accurate are spectrometer wavelength calibration light sources from Ocean Optics?

Ocean Optics only uses calibration light sources that can be traced back to a standard light source characterized at the National Institute of Standards (NIST). This does not mean necessarily that the specific light source used for calibration was measured at NIST. Light sources change their output over time as the bulb degrades, and therefore remain within acceptable calibration limits only for a limited amount of time.

It is common practice to keep a NIST traceable light source as a gold standard, and then use it to calibrate other light sources for use as working calibration standards. Each degree of separation from the NIST-calibrated light source introduces some uncertainty, yielding a total estimated uncertainty of within 10% for most Ocean Optics calibration light sources (a value that is typical for the industry). Repeatability of measurements made with a calibrated system will be much higher, typically within 2%.