An eye tracking system includes a transparent lens, at least one light source, and a plurality of light detectors. The transparent lens is adapted for disposal adjacent an eye. The at least one light source is disposed within the transparent lens and is configured to emit light toward the eye. The at least one light source is transparent to visible light. The plurality of light detectors is disposed within the transparent lens and is configured to receive light that is emitted from the at least one light source and is reflected off of the eye. Each of the light detectors is transparent to visible light and is configured, upon receipt of light that is reflected off of the eye, to supply an output signal.