When endeavoring to gauge the spectral resolution of a spectrometer guarantee that the deliberate flag is altogether slender to guarantee that the estimation is resolution constrained. This is regularly expert by utilizing a low weight discharge light, for example, a Hg vapor or Ar, since the linewidth of such sources is commonly much smaller than the spectral resolution of a dispersive exhibit spectrometer. In the event that smaller resolution is required, a solitary mode laser can be utilized.
After the information is gathered from the low weight light, the spectral resolution is measured at the full width half most extreme (FWHM) of the pinnacle of intrigue.
While ascertaining the spectral resolution (δλ) of a spectrometer, there are four qualities you should know: the opening width (Ws), the spectral scope of the spectrometer (Δλ), the pixel width (Wp), and the quantity of pixels in the indicator (n). It is likewise critical to recollect that spectral resolution is characterized as the FWHM. One exceptionally basic mix-up while figuring spectral resolution is to ignore the way that with a specific end goal to decide the FWHM of a pinnacle, at least three pixels is required, in this manner the spectral resolution (accepting the Ws = Wp) is equivalent to three circumstances the pixel resolution (Δλ/n). This relationship can be developed to make an esteem known as resolution variable (RF), which is dictated by the relationship between the opening width and the pixel width. As would be normal, when Ws ≈ Wp the resolution component is 3. At the point when Ws ≈ 2Wp the resolution calculate drops to 2.5, and keeps on dropping until Ws > 4Wp when the resolution figure levels out to 1.5.
For instance, if a spectrometer uses a 25µm opening, a 14µm 2048 pixel identifier and a wavelength extend from 350nm – 1050nm, the ascertained resolution will be 1.53nm.