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Maxwell2D: Campbell-Stokes sunshine recorder

Dielectric constant distribution

Campbell-Stokes sunshine recorders are widely used to record the duration of bright sunshine during the day. A glass globe focusses the light on to a card and as the sun moves across the sky, a scorch mark is left on the card, the total length of which is proportional to the number of hours of bright sunshine. In this case we have used a refractive index for crown glass of 1.52, corresponding to a dielectric constant of 2.31.
Wikipedia link: Campbell-Stokes recorder

Electric field animation

Time-averaged Poynting vector

This is an animation of the component of the electric field out of the plane of the page.The direction in which energy is travelling at any instant is proportional to the cross product of the electric and magnetic fields, known as the Poynting vector. The arrows show the direction of the Poynting vector averaged over the simulation, while the colours show its strength.