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Experimental set-up

Experimental set-up

Experimental set-up

Two half-silvered mirror

Precision Inferometer

In this session you will have:

Gained a proficiency in making fine adjustments of optical components


Understood how to use an interferometer


Obtained a practical understanding of the interference of light waves


Measured the wavelength difference between the sodium D lines


Observed the "beating" of these wavelengths by means of the interferometer


Practised taking clear and intelligible laboratory notes


Using a prism spectrometer, it is possible to measure the wavelength (λ=589.3 nm) of the characteristic yellow emission lines of a sodium lamp. However, the spectral resolution of a prism is insufficient to separate the two component emission lines, denoted D1 and D2. This can be achieved by means of a precision interferometer. In this experiment, you will measure the wavelength difference, λ21, between the sodium D lines using an interferometer in its Fabry-Perot mode of operation.

There is an ISE where you can practice this experiment before your session. It can be found here.



The script for this experiment can be found in the lab script book or on DUO.