Figure 2 | Scientific Reports

Figure 2

From: Wave optics of imaging with contact ball lenses

Figure 2

Nonparaxial ray tracing for a point source at the surface of a ball lens. (a) As the emission angle \(\alpha \) increases, the intersection \(x_c\) of the refracted ray with the optical axis can change from virtual to real and then disappear in the TIR case. (b) Propagation regimes for the refracted ray at various \(n_r=n_2/n_1\) and \(\alpha \). (c) Virtual and real intersections \(x_c/R\) versus \(\alpha \) for various values of \(n_r\) shown next to the curves.

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