•Spectrometer: measures I vs λ.
Simply measures the spectrum of the light (e.g. emission
spectroscopy).
•Spectrophotometer: measures I/I0 vs λ.
Measures how the sample changes the spectrum of the light (e.g.
transmission, reflection, scattering, fluorescence).
•All
spectrophotometers contain a spectrometer.
•-meter: the detector is electronic
•-graph: light intensity recorded on film
•photometer: measures I/I0 without λ selection.
•
•