Selecting an optical spectrum analyzer

One of the most common measurement instruments found in a modern optics laboratory is the optical spectrum analyzer (OSA). These instruments measure the optical power spectrum of light emitted from optical sources, as well as light generated from optical interactions with matter. OSAs are based on several technologies. Each technology offers strengths, but also has limitations. Choosing the correct technology for a measurement application requires understanding the concepts of sensitivity (the ability to measure low power optical signals), dynamic range (the ability to measure low power signals), resolution (the ability to measure two signals separated by a small wavelength difference), amplitude accuracy (the ability to measure the absolute optical power present), and wavelength accuracy (again, the absolute value)