All Questions
191
questions
5
votes
2
answers
231
views
Huygens' principle and the laws of reflection/refraction
As I understand the Huygens principle, all points on the wavefront are sources of secondary spherical wavelets and the tangent to these wavelets will form new wavefront. This is used to prove the ...
0
votes
0
answers
46
views
How can a greater than 1 reflectance coefficient be explained in $\rm SiC$-$\rm SiO_2$ interface?
I ran a simulation using the Transfer Matrix Method to plot the R,T and A curves for a SiC->SiO2 interface. There's a region of incident energies where the |r|^2 I get is higher than 1 and the ...
1
vote
2
answers
72
views
Why total reflection happens at only 1 angle?
The critical angle can be intuitively understood by Snell's law.If the incident medium has a bigger diffraction index than the refracted medium then according to Snell's law the refracted ray will be ...
5
votes
4
answers
1k
views
How do parallel reflected rays meet to form image at infinity? If they never meet then how is image formed?
In my textbooks it is written that when an object is kept at focus, its image is formed at infinity and is real. But how is this possible because parallel lines never meet and it is necessary for rays ...
0
votes
0
answers
31
views
Property of total internal reflection question
If I create a medium with gradually decreasing refractive index from once face at index 2.0 and other at 1.01, and show a beam of light upon the optically denser side, will there be any losses upon ...
1
vote
2
answers
77
views
Deviation suffered by light ray incident on a surface
Problem:
Figure shows two spherical surfaces of radii $R$ and $2R$ separating three transparent media of refractive indices $\mu_1=1, \mu_2=2$ and $\mu_3=4$. A ray of light travelling in medium $\...
0
votes
2
answers
75
views
Is there a way to calculate the angle between the refracted and reflected rays given the refractive index?
Is there a way to calculate the refracted and reflected rays? I know we use Snell's law to calculate the refracted rays, but is there a formula to calculate the angle of the reflected rays, or does it ...
0
votes
0
answers
68
views
Finding the limiting refractive index of a rainbow
Give the limiting refractive index of a rainbow.
The raindrops are modelled as spherical droplets, with refractive index $n$, with parallel rays from the Sun incident on it. I have a very limited ...
0
votes
0
answers
29
views
Minimum Radius of Curvature an Optical Fiber can be bent
Using the thickness and refractive index of an optical fiber, is it possible to know the maximum radius of curvature it can be bent before there are losses due to refraction?
In my research, I came ...
10
votes
1
answer
2k
views
How does a Magic Mirror work?
I recently found out about the Magic Mirror. Both sides of the mirror look the same, and it appears to be dark, if looked at closely, like sunglasses (but lighter in colour) but looks like a normal ...
0
votes
1
answer
51
views
What causes light to scatter in a medium?
My understanding is that all mediums have a complex iindex of refraction where the real component is the "standard" index of refraction, and the imaginary component is the extinction ...
0
votes
1
answer
184
views
Complex Refractive Indices, Absorption, and Transparency
A complex refractive index is defined as $n = n_0 + \kappa$ where $n_0$ is the "standard" refractive index, and $\kappa$ is the optical extinction coefficient. The optical extinction ...
2
votes
1
answer
201
views
Lenses and missing reflection
I am wondering why reflected rays are not considered with lenses. If a ray strikes a surface, another is reflected off that striking point; however, this is not added when studying lenses, only ...
1
vote
0
answers
31
views
Fresnel Equations and an Opaque Surface?
I'm trying to make sense of what actually happens to light when it interacts with an opaque surface.
The fresnel equations give us the proportion of light which is reflected off the surface of a ...
0
votes
0
answers
75
views
Perceiving the rainbows
Famous Astrophysicist Dr Neil DeGrasse Tyson, explains that whenever we observe a rainbow it appears exactly semi-circle to us. If another person is observing the same rainbow from a slightly ...