The museum has a very rare 7J20 / J20 rapid scan spectrometer on display. This product only appears in the 1975 product catalog as shown below. The 7J20/J20 plugin sold for $12,000 in 1975, equivalent to over $50,000 dollars today.
Rapid scan refers to the fact this spectrometer can capture the spectrum quickly enough to show real time changes in the optical spectrum. At the museum we use a multi-color LED bulb which cycles through several colors which are instantaneously displayed on the spectrometer. It is also sensitive enough to show the baseline of the ambient background room lighting.