# Ray Tracing - Optics - Bend light with circular lenses

1. Apr 3, 2015

### johanns

Hey guys first time poster.

I have written a 2D ray tracer in Mathematica. It's very basic, all it does is use Snell's law to trace ray refraction and very basic absorption. The set up is a central absorbing circle surrounded by circular lenses. The central circle is a perfect absorber, so if a ray encounters it it is totally absorbed. The outer circles are perfect transmitters and if a ray encounters them it is refracted and transmitted.

This was just something I wanted to experiment with to see if I could bend light around and object. The results are pretty cool and the light seem to bend so perfectly I'm a bit suspicious. Can someone who know a lot about optics take a look a the results and tell me if you think they are within the realms of possibility.

The lenses have a refractive index of 1.65.

I have included a picture but I have also included a link to a vector file (.svg) which can be opened in any web browser and you can zoom in to your hearts content (ctrl +)

NB the blue line is tangent to the large circle and parallel to all initial rays, so any rays that appear on the right half of the image would otherwise have been absorbed (ignoring diffraction)

Thanks

2. Apr 7, 2015

### RaulTheUCSCSlug

I am not sure if I am just confused from your picture or what, but I believe that rays should be bending around the object, and from the picture it seems as though the rays are bending out the object. Does that make sense?

Also assuming that the rays from the right, their thickness is the amount of light that is being reflected around the object, the thickness seems to coincide with reason. Since less and less light should bend away towards the object which is what is being shown.

3. Apr 12, 2015

### johanns

Hi there thanks for your reply. Just to clarify the rays are approaching the object from the left. The small circles are lenses which totally transmit light, and the big thing absorbs light. The rays on the right are rays that would otherwise have been absorbed by the big circle, but have instead been refracted (not reflected) around the big circle. Their thickness is just where multiple rays have lined up close together making what appears to be a thicker ray.

4. Apr 13, 2015

### RaulTheUCSCSlug

Then yes, the refraction does seem to make sense, whether it makes sense mathematically I wouldn't be able to tell you.