The wavelengths and the corresponding lengths of coherence of the green spectral lines of an extreme high pressure Hg vapour lamp are determined by means of a Michelson interferometer. Different double slit combinations are illuminated to verify the coherence conditions of non punctual light sources. An illuminated auxiliary adjustable slit acts as a non punctual light source.
- study the quantity that allows light to be used in interference experiments
- analyze different spectral lines of a mercury lamp
- make practical use of a Michelson interferometer to characterize light
- Determination of the wavelength of the green Hg spectral line as well as of its coherence length.
- The values determined in 1. are used to calculate the coherence time and the half width value of the spectral line.
- Verification of the coherence condition for non punctual light sources.
What you can learn about
- Fraunhofer and Fresnel diffraction
- Spatial and time coherence
- Coherence conditions
- Coherence length for non punctual light sources
- Coherence time
- Spectral lines (shape and half width value)
- Broadening of lines due to Doppler effect and pressure broadening
- Michelson interferometer