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Question
What is the difference between Fresnel and Fraunhofer diffraction?
Solution
No. | Fresnel diffraction | Fraunhofer diffraction |
i. | The Source of light and screen is kept at a finite distance. | The Source of light and screen is at infinite distance. |
ii. | Spherical or cylindrical wavefronts are considered. | Only plane wavefronts are considered. |
iii. | It is observed in straight edge, narrow slit, etc. | It is observed in the single slit, double slit, etc. |
iv. | Lenses are not used. | Convex lenses are used. |
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