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

Click For Summary

Discussion Overview

The discussion revolves around the behavior of light observed in a coffee cup, particularly focusing on the visual effects created by the interaction of light with the cup's shape and the surrounding LED lights. Participants explore concepts related to caustics and optical phenomena, with references to mathematical descriptions and visual representations.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • One participant asks about the number of LED lights and describes the appearance of light resembling a "double volcano," inviting others to explain this phenomenon with equations.
  • Another participant references caustic optics and provides links to articles that discuss the topic further.
  • Some participants suggest that the visual effect is due to spherical aberration caused by the coffee cup's shape, which focuses light similarly to a spherical mirror.
  • A participant shares a rendering of light reflecting off a semi-circular surface, noting the interesting patterns that can emerge from such reflections.
  • One participant discusses their experience with caustic optics in visual filmmaking, mentioning the use of reflective materials and warped glass to create light textures.
  • Another participant expresses appreciation for the shared video related to the topic and mentions plans to release more content that explores scientific concepts relevant to their films.

Areas of Agreement / Disagreement

Participants generally agree on the relevance of caustic optics to the observed phenomenon, but there are varying interpretations of the specifics, such as the number of light sources and the exact nature of the visual effects. The discussion remains open-ended without a definitive conclusion.

Contextual Notes

Some assumptions about the light sources and the specific conditions of the observation are not fully explored. The discussion includes references to mathematical concepts and visual representations that are not resolved within the thread.

Who May Find This Useful

Individuals interested in optics, visual effects, and the interplay of light with different materials may find this discussion relevant, particularly those exploring practical applications in filmmaking or scientific visualization.

Anshul23
Messages
9
Reaction score
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
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   Reactions: Anshul23
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   Reactions: Anshul23
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   Reactions: Anshul23
OmCheeto said:
Looks like two to me.
Correct
 
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   Reactions: Anshul23 and Drakkith
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   Reactions: 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   Reactions: Anshul23

Similar threads

  • · Replies 5 ·
Replies
5
Views
5K
  • · Replies 4 ·
Replies
4
Views
3K
  • · Replies 4 ·
Replies
4
Views
9K