GOALS
Physics
- Measure the coherence length of light using an interferometer.
- Technique
- Use a Michelson Interferometer to measure the coherence length of
filtered light from a mercury lamp.
- Use the interferometer to measure the coherence length and bandwidth of a
`white' light source.
-
Errors
- Attempt to place an upper limit on
for the mercury green line by seeing how large l2 - ll
can be made with the fringes still visible.
- Is the coherence length you infer for the white light source consistent
with what you already know about the bandwidth?
Question
- Yellow sodium light consists of two wavelength, 5890 and 5896 angstroms.
The interference pattern disappears and reappears periodically as l2
is increased. What is l2 - l1 between two successive
reappearance of the interference pattern?
References
- Halliday and Resnick, 37.6.