Patent attributes
A lens of a side emitting LED includes a bottom surface, an incident surface, a reflective surface, a first refractive surface, a second refractive surface and a third refractive surface. An light emitted by a LED enters the lens through the incident surface. A portion of the light is reflected by the reflective surface in an internal total reflection manner to the second refractive surface and emits out of the lens along a first optical path. The other portion of light directly emits out of the lens through the first refractive surface and the third refractive surface. A transitive surface is located between the first refractive surface and the reflective surface. Such a design allows the light entered the lens through the incident surface not cross with the transitive surface. Hence an improper reflection or refraction can be prevented.