Once the intensity profile of a 785 nm excitation Raman spectrometer has been standardised, e.g. using either white light or NIST SRM-2241, these can be routinely monitored using the same primary standard. However, these aren't ideal candidates for daily monitoring of multiple units in a production environment. It would be preferable to use a custom made-to-requirements secondary standard to measure every single session that would monitor intensity profile. This would then be compared to the primary standard at regular intervals.

Does anyone have any reliable materials that can be dependably sourced to give

1) consistent broadband raw signal

2) remain stable over at least 12 months

3) minimal photobleaching?

I have considered sourcing green glass microscope covers but does anyone manufacture them reproducibly enough? I'm assuming that their intensity profile in a Raman setup is not something they are likely to be analysed for in QC, but maybe their emission spectra are?

Also, I've considered fluorescent polymer sheets, but it isn't easy finding out about quantum efficiency in the NIR, mostly I find only lambda max. I'd also be concerned about photobleaching occurring too fast. Then I imagine the QE of the fluorescence would need to be >10,000x higher than the QE of any Raman modes , preferably 1,000,000x.