Magnetic Lens
The magnetic lens consists of three parts: a radial field with a flux decreasing towards the optical axis, which makes particles at the outer rim perform a spiraling motion, a homogeneous magnetic field along the optical axis which leads to the focusing Lorentz force, and a second part with a radial field undoing the spiraling. Again the indirectness leads to the fact that the resulting refractive power is the square of the refractive power of a single lens.
Read more about this topic: Electrostatic Lens
Famous quotes containing the word magnetic:
“We are in great haste to construct a magnetic telegraph from Maine to Texas; but Maine and Texas, it may be, have nothing important to communicate.”
—Henry David Thoreau (1817–1862)