Refraction related issue

[alexgrdem]

Hello everybody,

I am trying to model a fresnel lens. Since, rays are perpendicular to the front face of the lens, I am using a single element for refraction. Optical properties are shown below:

addoptic('Refractive Sample');
opticopt('Refractive Sample', 1, {'refl'=0.0, 'refractr'=1.49, 'trans'=1.0, 'errslope'=0.001, 'errspec'=0.001 } );
opticopt('Refractive Sample', 2, {'refl'=0.0, 'refractr'=1.0, 'trans'=1.0, 'errslope'=0.001, 'errspec'=0.001 } );

With these settings, I do not expect reflected rays and also, the maximum number of rays used for the first stage to strike the receiver. (The receiver is a very large horizontal surface located below the lens). However, there exist a small number of rays that appear to be reflected.

Is there a known issue of bug related to the above problem or am I missing something here?

Hope to hear from you,
Alex

[MCilento93]

Did you check the properties given to the other side of the facets?

[AdamRJensen]

Hi @alexgrdem, did you succeed in your Fresnel model?

From what I understand every time that a ray changes between two mediums with different refractive indexes (e.g. air to glass) there will always be some reflections.