All Questions
Tagged with optics diffraction
515
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Diffraction grating from reflection
We had an experiment in our physics lab where we used two grating materials one with 2500 lpi(say A) and the other with 15000lpi(say B).
Now when we shine white light on both of them we didn't get any ...
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4
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86
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Diffraction proof
I am talking about the way we generally explain the occurence of bright and dark fringes during diffraction. When we want to show a dark fringe we consider a pair of secondary light sources who have a ...
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Polarization of electric field and its effect on the Poynting vector
To preface, I've little experience with optics. This is a very use-case specific project I'm undertaking. So, if there are any improvements in my method, I'd appreciate it!
I'm working with the vector ...
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How is the Huygens-Fresnel principle of diffraction modified when light is confined to a planar dielectric waveguide?
The Huygens-Fresnel principle essentially states that in order to propagate an electromagnetic wavefront in free-space, one must superimpose the so-called "secondary wavelets", which are ...
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Modeling hair strand diffraction?
It's well known that a human hair can diffract light (plenty of demos out there, all you need is a laser pointer and a strand of hair). I've been thinking, however: how can one model this process? The ...
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Why diffraction works at sharp edges?
While introducing Diffraction, physics textbooks say that this effect (Diffraction) is observed distinctively when the light is passed through a very small opening, the length or diameter of which is ...
- 2,517
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Calculating net phase in single slit diffraction
I want to calculate the net phase at a point on the screen in Fresnel diffraction. Attached below is a rough diagram if needed.
For this I considered hypothetical $n+1 $ small slits acting as sources ...
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Why Do Harmonic Components Define Wavelength in Diffraction and Interference Phenomena?
I'm exploring the physical principles underlying diffraction and interference, specifically how these phenomena depend on the wavelength of harmonic (sinusoidal) components of a wave. My question ...
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Need clarity behind the theory of diffraction for a black-body source
Attempting to model the diffraction for a black-body source, I have stumbled upon a bit of a conundrum with the mathematics. I am not asking WHY the light is diffracted, but instead looking for a ...
- 553
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3
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166
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Interference in single slit
In my point of understanding, interference is produced when waves from two sources of light (may be coherent or non-coherent) overlap resulting in consecutive bright and dark fringes on a screen. But, ...
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How to explain interference pattern in our eye?
Suppose we got a Lamp L that emits some light. The light afterwards hits a diffraction Grating G at a distance a. Now if you were to look through the grating with your Eye E, you were to see the ...
- 462
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Double slit diffraction integral?
In our physics class, the professor went over a so-called "diffraction integral" for single slit diffraction:
$$E = E_0\cos(kx - kct)\qquad\text{then we ignore time dependence}:$$
$$E = E_0\...
- 187
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119
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Minimum intensity fringes are not perfectly dark in diffraction pattern?
I am studying Interference and Diffraction and everywhere I look it is written that "In an interference pattern,the minima are usually perfectly dark while in a diffraction pattern they are not ...
2
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Why doesn't a lens after a diffraction grating affect the optical path difference?
When observing interference fringes one often uses a lens after the diffraction grating to focus the fringes on a screen like this:
At first sight, one might think that after the lens the path ...
- 1,702
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How does a Circular Light Source create Shadows with Darker Edges Sometimes?
Problem:
There is a room where the light fixture is circular*. Shadows of objects in this room are darkest in the center and brighter toward the edges, except for my phone charger. Its shadow is ...
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