Demonstrations of optical spectra with a video camera

The use of a video camera may markedly improve demonstrations of optical spectra. First, the output electrical signal from the camera, which provides full information about a picture to be transmitted, can be used for observing the radiant power spectrum on the screen of a common oscilloscope. Second, increasing the magnification by the camera enhances the resolution of the spectra displayed by a colour monitor. In particular, it becomes possible to resolve the sodium doublet at 579nm (Δλ = 0.6nm).