How to recreate 1st prize photo of the Einstein Year Award?

[cappez]

I've been very much intrigued by this picture of the surface tension of water supporting a metal paperclip:

http://www.visions-of-science.co.uk/winners2005/win-18.htm"

"By photographing it using a grill in front of the light source, the deformation of the water caused by the clip's weight can be seen."

Does anyone know how to recreate the effect shown in this picture?

 

[neutrino]

I don't have an answer for your question, but thanks for the link.

 

[cappez]

I was actually wondering if the 'bending of light' around the paperclip is just the result of a special grill, or if the deformation of the water could actually create such an interesting effect. It does say: "By photographing it using a grill in front of the light source, the deformation of the water caused by the clip's weight can be seen." If its not the grill (except of course for the horizontal lines), then that's a really amazing effect. I'd love to try that at home.

 

[Kurdt]

Basically the grill causes an interference pattern which gives the light and dark bands on the water. Since the water surface is deformed by the paperclip the reflection of these bands gives a kind of contour map of how the water is reacting under the paper clip. Very simple but highly effective, you can even try it at home but make sure you only use one light source.

 

[cappez]

Hi Kurdt,
Thanks for your reply. Do you think you need some special equipment? With polarized light the outer ridge of the deformation lights up, but I've had no success with my attempt at creating those neatly striped lines. A paperclip is pretty small so those stripes have to be extremely narrow.

 

[Kurdt]

Well you really have to have a grill that is very narrow indeed compared with the wavelength of light. Try some sort of comb and make a rectagle of spacings from it. Failing that steal a grill from your local physics department.

 

[Kurdt]

You need no polarised light just a single source and a fine grill. By fine I mean that the spacings are of approximately the same wavelength of the light that you are using as the source. This should hopefully recreate the kind of pattern you hope for.

 

[Integral]

I think you are way off track. The light and dark lines are not a defraction effect but simply shadows. You need a grating, but the spacing will be >> [itex] \lambda [/itex] of your light source. You may also need to play with the distance between the grating and the light source.

 

[Danger]

Would light reflected from a diffraction grating foil or CD work?