Why Is the Center of Newton's Rings Dark?

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The center of Newton's rings appears dark due to the phase difference between two reflected rays, despite the path difference being zero when the surfaces are in contact. When the surfaces are slightly separated, this phase difference becomes significant. The interference pattern created by the light waves results in a dark center, which can be counterintuitive since one might expect brightness with zero path difference. Understanding the role of phase difference is crucial in explaining this phenomenon. The discussion emphasizes the importance of both path and phase differences in optical interference.
sheld
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Why the center of Newton's ring is dark? though I am thinking the path difference in the center is zero between two reflected rays...
so,I will be glad if you give the correct information about that...
 
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As long as the surfaces are in contact the path difference in the middle is zero. If you move them slightly apart you can change this.
 
sheld said:
Why the center of Newton's ring is dark? though I am thinking the path difference in the center is zero between two reflected rays...
so,I will be glad if u give the correct information about that...
The phase difference between the two reflected ways counts, and it is not zero, even in the case when the path difference --->0.
 
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