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Laser

Posted: Fri Mar 13, 2009 8:02 pm
by CRAS
Hi

I tried to simulate a laser LED with a point light source and a perfect parabolic reflector. I even thought about to add a reflector to cover the direct emitted light.

What maxwell gives back is similar to a spot with a opening angle of approx. 3-4°

Has anyone experience with this?

Thanks[/img][/b]

Posted: Fri Mar 13, 2009 8:11 pm
by polynurb
Hi CRAS,

this is from an old thread, tried it some time ago.. seemed to work quite well.

Hello all,

maybe that is also an approach:

I did some tests recently with Parabolic reflectors in rhino, locating a very small
emitter square in the focus of the revolved parabola.

after some tweaking of size ( the emitter was 0,002m in size) and meshing resolution of the parabola (the higher the better for accuracy) I was able to cast rays almost parallel over the distance of 1km.
the parabola itself was 5m in diameter. same as the "red spot" which was hit.
You can still see that the emitter was square.
I used a very low power skydome to show the grid in the render, so there is no scattering of the emitter.
I think that system should be "scalable" with changing the emitter power at the same time; haven`t tested more yet.. like noise clearing etc.
Image

Posted: Wed Mar 25, 2009 9:05 pm
by CRAS
Hi polynurb,

It´s the meshing of the parabolic reflector - now it´s clear!
My beam is 3mm in diameter and the light source @ 0,0015mm.
The mesh was far to coarse...

Can you tell me how I can change the parameter responsible for controlling the mesh generation process (SolidWorks) ?

Again thanks

Posted: Thu Mar 26, 2009 1:23 am
by polynurb
..sorry don't know about SW.. but you'll for sure find the answer in the SW section of the forum :wink:

Posted: Fri Apr 03, 2009 10:53 am
by jfrancis
Image

Image

Other tests here...

Posted: Sun Apr 05, 2009 1:20 am
by jfrancis
I use one of Maya's regular 'Platonic solids' for the emitter to keep the polygon density and size about the same in all directions.

Posted: Mon Apr 06, 2009 4:29 am
by Cadhorn
Thanks for the parabola info/tests jfrancis. Very very useful!!

Posted: Mon Apr 06, 2009 4:49 am
by jfrancis
Thank you. :D

It's amazing to me that the ellipsoid and parabola, that look pretty similar at first glance, behave so differently.

Posted: Mon Apr 13, 2009 9:13 am
by jfrancis

Posted: Mon Apr 13, 2009 9:14 am
by jfrancis