主权项 |
1. A light guide apparatus having a core, the core comprising:
a first optically transparent section comprising a first optical medium having a first index of refraction; and a second optically transparent section comprising a second optical medium having a second index of refraction, an interface between the first optically transparent section and the second optically transparent section defining a shape; the shape, the first index of refraction and the second index of refraction being configured such that light entering the core in a predetermined angular range is deflected, deflection comprising refraction, at the interface between the first optically transparent section and the second optically transparent section at an angle such that, when light impinges on a core-cladding interface, the light impinges on an interface between the core and a cladding at an angle at least equal to a critical angle for total internal reflection. |