Wide-range wavelength modulation spectrometer.
A wavelength-modulation spectrometer with a spectral range of 2000-8000 A has been constructed. The system measures simultaneously the derivative spectrum and the conventional spectrum. The derivative spectrum has a sensitivity of DeltaR/R ~ 10(-5) and is completely free of background trouble. With proper changes in the optical components, the spectral range of the spectrometer can be extended further into the infrared and into the uv.