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Difference between Fresnel and Fraunhoffer diffraction in tabular form

The essential distinction among Fresnel and Fraunhoffer diffraction is that in Fresnel diffraction
the source of light and screen is at a limited distance from the screen, while in Fraunhoffer
diffraction assuming that the source of light and screen is at a infinite separation from the
obstacle
...
In this
present circumstance, the wavefronts falling on the obstruction are not planes
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What is Fraunhoffer diffraction? ,
Fraunhoffer diffraction can be noticed on the off chance that the source of light and screen at
which the diffraction design is shaped is set at an endless separation from the diffracting
obstacle
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One focal point is put
between the source of light and the obstacle while the other focal point is set between the
obstacle and screen
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Major difference between Fresnel and Fraunhoffer diffraction
Fresnel Diffraction
1: If the source of light and screen is at a finite distance from the obstacle, then the diffraction
called Fresnel diffraction
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3: The wavefronts falling on the obstacle are not plane
Fraunhoffer diffraction
1: If the source of light and screen is at infinite distance from the obstacle then the diffraction is
called Fraunhoffer diffraction
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3: The wavefronts falling on the obstacle are planes
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The amplitude
distribution for diffraction because of a round gap shapes a power design with a bright focal
band encompassed by concentric roundabout groups of quickly diminishing power (Airy
Example)
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75% of the central intensity 84% of the light
Shows up inside the central peak called the breezy disk
Allow us to consider a circular gap of width d is displayed as AB in figure
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Each point on the plane wave front in the opening
goes about as a source of optional wavelets
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These diffracted optional wavelets are joined on the screen SS'
by keeping a convex lens (L) between the gap and the screen
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Those diffracted beams going typical to the plane of opening [i
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, along
CPO] are get combined at PO
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Subsequently a bright spot is framed at PO known as Airy's
circle
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Next consider the optional waves going at a point θ regarding the bearing of CPO
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The span of that ring is x and its middle is at PO
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The way contrast is BD = AB sin θ = d sin θ
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Subsequently, the force at P1 relies upon the
way contrast d sin θ
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Then again, on the off chance that the way distinction is in odd products of pictures,
the power is most extreme
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e
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n = O corresponds to central maximum
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The intensity of the dark ring is zero and the intensity of the bright ring

Decreases as we go radially from PO on the screen
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Sin x/l
Where, f is the focal length of the lens
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22 ƒ
d

Using equation above the radius of Airy’s disc can be obtained
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Hence by decreasing the diameter of aperture, the size of Airy’s disc increases

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