All Questions
Tagged with optics visible-light
1,367
questions
3
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1
answer
158
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Infinite reflection inside a glass loop
If you had a loop made of completely transparent glass (or other material), in the shape of a donut; think atomic collider (but probably not needing to be so large :) ), and you introduced light from ...
0
votes
1
answer
74
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Let's say I have manufactured a prism from a non-dispersive medium, then light coming from air wouldn't split into colours right?
Let's say I have manufactured a prism from a non-dispersive medium, then light coming from air incident on the prism wouldn't split into colours, right? I mean light still changes direction, but all ...
- 959
2
votes
1
answer
119
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What is the speed of light in case of Critical Angle?
When light travels from an optically denser to a rarer medium, it bends away from the normal and at a specific angle of incidence, the angle of refraction is ${90}^{\circ}$. When the angle of ...
0
votes
2
answers
63
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Which factors determines whether a photon is absorbed? [duplicate]
After some research, I figured out that all EM waves/photons are absorbed by atoms by exciting an electron from an orbital to an other. However, atoms emit only certain EM waves with specific ...
- 167
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votes
0
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60
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Schlick's approximation for reflectance when $n_1 = n_2$
another raytracer here.
I'm using Schlick's approximation to the Fresnel equations, which is said to be reasonably faithful.
I'm a little puzzled about the situation where the incident ray is just ...
- 101
8
votes
1
answer
504
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Skylight reflection shows birefringence patterns
I noticed that the skylight where I work looked white to me, but its reflection from the tiles below showed a colorful pattern. See the images below, and also a video that shows this effect from ...
- 12.5k
3
votes
0
answers
61
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Why is sunset in mars blue?
This is the Martian sunset, as captured by the Spirit rover of NASA. Notice the colors are inverted, i.e. the direct rays blue and diffused rays red, which is exactly the opposite of what you would ...
- 12.5k
0
votes
0
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32
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Is there really a relation between light intensity and color saturation?
Going through this article on Wikipedia, under the saturation section, I came across "The purest (most saturated) color is achieved by using just one wavelength at a high intensity, such as in ...
- 1,096
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1
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83
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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
6
votes
2
answers
2k
views
Wavelength of "complementary colours"?
In physics/chemistry/the life sciences there's a common experimental method of determining the concentration of a sample using spectrophotometers. We can measure the absorbance of the sample at a ...
- 687
1
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2
answers
64
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Conflicting lensmaker's equation representation
I keep finding these two conflicting forms of the lensmaker's equation. I understand that (n2-n1)/n1 is the same as (n-1) if referring to a lens in air, but I can not make sense of why the reciprical ...
- 23
3
votes
1
answer
62
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Can a system of lenses or compound lens have a higher numerical aperture than a single element in the system?
I am attempting to create a simple Abbe condenser for a microscope, which typically consists of two converging lenses.
Ideally, I would like to achieve a numerical aperture for the condenser of ...
- 33
0
votes
0
answers
55
views
Is the Fourier Transform a reliable way to infer the physical phenomena producing an RF signal?
Consider the following thought experiments:
Scenario 1:
A person standing far away shines 3 light beams at you, each beam having a narrow spectral distribution centered around different frequencies F1,...
- 139
0
votes
0
answers
30
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Is it preferable to say $v$ is " image distance " than to say " image position " in spherical mirror formula?
I was going through spherical mirror formula $1/v + 1/u = 1/f$ where $u$, $v$ and $f$ are named as object distance, image distance and focal length respectively. But while using this equation we do ...
- 1,357
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1
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55
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Can I recover the physical wavelengths present in a light source from a time-series measurement of its amplitude?
Consider a mixture of different wavelengths being emitted from the same point (ex: a star). This light consists of a mixture of wavelengths and intensities at each wavelength. When measuring the ...
- 139