why unequal fringe width in Michelson interference pattern?
Welcome to PF;
If I understand you correctly - this is due to imperfect equipment.
I don't think it is due to apparatus imperfection. There is a formula for fringe width which is given by β=λ/2nθ, where n is the order of the fringe. but none of the text book has given the explanation for this.
If you post a vague message, and come in once a month to update it with only minimal new information, it will take you a very long time to get your answer.
Well then I clearly did not understand you. You will have to provide more information about what you are talking about.
see the equation for circular fringes about half way down the page.
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