Michelson interferometer - change splitting pattern

[jaejoon89]

How would you change the splitting patterns for an interferometer? (Specifically a Michelson interferometer, if it matters) How would changing the fixed mirror, movable mirror, etc. affect the pattern?

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We just started learning some optics, and are just supposed to understand this conceptually or with a minimum amount of math.

 

[LowlyPion]

Perhaps read a little of the set-up:
http://en.wikipedia.org/wiki/Michelson_interferometer#Configuration

And think about which variables of the lab bench would affect the wavelengths that will be generating interference?