An eye tracking system , comprising: an infrared light source ; scanning optics configured to scan light from the infrared light source across a region comprising a user's cornea; a plurality of photodetectors (208; 402), each photodetector being configured to detect infrared light reflected from the user's cornea at a corresponding angle; a plurality of current to voltage converters (308; 408), such that for each photodetector, a corresponding current to voltage converter (308; 408) is configured to output a voltage based upon a current received from the photodetector; a pupil location processing system comprising a summing junction (314; 420) configured to sum analog voltage signals received from the plurality of current to voltage converters to obtain an analog voltage signal sum, an analog to digital converter (316; 422) configured to convert the analog voltage signal sum to a digital voltage signal sum, and a scanning mirror trajectory calculator configured to calculate a current mirror pointing angle of a scanning mirror of the scanning optics and output the digital voltage signal sum into a pixel of a frame buffer based upon the current mirror scan angle; and a glint location processing system comprising, for each photodetector, a comparator (322; 410) configured to receive the voltage from the corresponding current to voltage converter and output a digital state based upon comparing the voltage to a reference voltage, and an interrupt handler configured to receive the digital state from each comparator and to obtain a time value when the digital state from any of the comparators changes value, the time value corresponding to a time at which a glint has been detected by a photodetector; and the glint location processing system is further configured to derive the location of a glint based on the time at which the glint is detected and the scanning optics. an infrared light source ; scanning optics configured to scan light from the infrared light source across a region comprising a user's cornea; a plurality of photodetectors (208; 402), each photodetector being configured to detect infrared light reflected from the user's cornea at a corresponding angle; a plurality of current to voltage converters (308; 408), such that for each photodetector, a corresponding current to voltage converter (308; 408) is configured to output a voltage based upon a current received from the photodetector; a pupil location processing system comprising a summing junction (314; 420) configured to sum analog voltage signals received from the plurality of current to voltage converters to obtain an analog voltage signal sum, an analog to digital converter (316; 422) configured to convert the analog voltage signal sum to a digital voltage signal sum, and a scanning mirror trajectory calculator configured to calculate a current mirror pointing angle of a scanning mirror of the scanning optics and output the digital voltage signal sum into a pixel of a frame buffer based upon the current mirror scan angle; and a glint location processing system comprising, for each photodetector, a comparator (322; 410) configured to receive the voltage from the corresponding current to voltage converter and output a digital state based upon comparing the voltage to a reference voltage, and an interrupt handler configured to receive the digital state from each comparator and to obtain a time value when the digital state from any of the comparators changes value, the time value corresponding to a time at which a glint has been detected by a photodetector; and the glint location processing system is further configured to derive the location of a glint based on the time at which the glint is detected and the scanning optics. <EOS>