Light in a cup (Can you explain this phenomenon?)

In summary, the conversation discusses the behavior of light in a room with LED ceiling lights on, specifically the appearance of light resembling a double volcano. The discussion delves into the use of caustic optics and the creation of visually stunning films using reflective materials behind a warped piece of glass. The individual also shares plans for releasing more interesting films and content specifically for PhysicsForums to review.
  • #1
Anshul23
9
1
LIGHT.jpg

Can anyone explain the behavior of light I came across as I sat in my lounge this evening having a nice cup of Mocha . Hint ( I am sitting in a room with some led ceiling lights on) can you:
1.Guess how many Led lights I have on
2.Explain the appearance of light which is looking like a typical double volcano lol.
3. Do try to express the situation in terms of elaborate equations.
 
Last edited by a moderator:
Science news on Phys.org
  • #3
DrClaude said:
https://en.wikipedia.org/wiki/Caustic_(optics)

http://lacim.uqam.ca/~plouffe/cercles/circles.html
Damn! this fast. I thought of tachyons for a moment :D But still how many sources of light
 
  • #4
Anshul23 said:
Damn! this fast. I thought of tachyons for a moment :D But still how many sources of light
Looks like two to me.
 
  • Like
Likes Anshul23
  • #5
Anshul23 said:
2.Explain the appearance of light which is looking like a typical double volcano lol.

Each "volcano" is the result of massive spherical aberration of the focused light. The coffee cup is circular in shape and focuses the light similar to a spherical mirror, except only in one dimension. See the diagram of the concave mirror in this article: https://en.wikipedia.org/wiki/Spherical_aberration
 
  • Like
Likes Anshul23
  • #6
Here's a quick render of light reflected from the inner side of a semi-circle. You can get some really pretty patterns just by reflecting light off of curved surfaces
ringreflec.png
 
  • Like
Likes Anshul23
  • #7
OmCheeto said:
Looks like two to me.
Correct
 
  • #8
Yeah it is caustic optics, I play around a lot with this for some of the visual films I create. Check out the film below, I use various reflective materials behind a warped piece of glass, shining various lights and lasers at it from different angles, filmed out of focus to amplify the textures of light..

https://vimeo.com/mistermishka/space008
 
  • Like
Likes Anshul23 and Drakkith
  • #9
mister mishka said:
Yeah it is caustic optics, I play around a lot with this for some of the visual films I create. Check out the film below, I use various reflective materials behind a warped piece of glass, shining various lights and lasers at it from different angles, filmed out of focus to amplify the textures of light..

https://vimeo.com/mistermishka/space008
Thats a great video BTW
 
  • Like
Likes mister mishka
  • #10
Anshul23 said:
Thats a great video BTW

Thanks!

Yeah I have lot more interesting stuff already filmed, but am working on releasing them this fall with music mixes (9 hours of my best stuff, from my 55 hours of footage). However, I will also be making a small selection of content solely for PhysicsForums review, because of the interesting science behind some of my films that I think people here would like. Also since I have used these forums a lot to actually get an understanding of what is actually happening with certain experimental filming techniques I've found out (things like polarizing light, diffraction, fractals, etc).
 
  • Like
Likes Anshul23

1. What is "Light in a cup"?

"Light in a cup" is a phenomenon where a cup or container filled with water and placed in direct sunlight appears to emit a bright light from within. This is caused by the refraction and reflection of sunlight through the water, creating a concentrated beam of light.

2. Why does the water in the cup appear to glow?

The water in the cup appears to glow because of the refraction and reflection of sunlight through the water. When light enters the water, it bends and changes direction, creating a concentrated beam of light that appears to glow from within the cup.

3. Can this phenomenon occur with any type of cup or container?

Yes, this phenomenon can occur with any type of cup or container, as long as it is filled with water and placed in direct sunlight. The size and shape of the cup may affect the intensity and direction of the light, but the general phenomenon will still occur.

4. Is "Light in a cup" the same as a rainbow?

No, "Light in a cup" and a rainbow are not the same phenomenon. A rainbow is caused by the refraction and dispersion of sunlight through water droplets in the atmosphere, while "Light in a cup" is caused by the refraction and reflection of sunlight through water in a cup or container.

5. How long does the "Light in a cup" phenomenon last?

The duration of the "Light in a cup" phenomenon depends on the position of the sun and the movement of the cup. If the cup is kept in direct sunlight, the phenomenon will continue until the sun moves or the cup is moved. However, if the cup is moved or taken out of direct sunlight, the phenomenon will quickly disappear.

Similar threads

  • Astronomy and Astrophysics
Replies
3
Views
1K
  • General Discussion
Replies
4
Views
584
  • Thermodynamics
Replies
1
Views
5K
Replies
8
Views
2K
Replies
10
Views
2K
Replies
48
Views
5K
  • General Discussion
Replies
4
Views
7K
  • MATLAB, Maple, Mathematica, LaTeX
Replies
8
Views
3K
  • MATLAB, Maple, Mathematica, LaTeX
Replies
6
Views
3K
Back
Top