How to calculate phase difference from path difference - Physics - Wave Optics

Question

How to calculate phase difference from path difference

Priyabrata Mondal · Accepted Answer

Dear student,
<img alt="" src=
"https://s3mn%20mnimgs%20com/img/shared/content_ck_images/ck_5da4b899a6c65%20jpg">
Regards

How to calculate phase difference from path difference.. . .