Abstract: An optical sensor for monitoring a utility meter having a sweep hand indicator that moves over a meter surface of the utility meter. The optical sensor has a single infrared light emitter and two photo diodes detectors. The infrared light emitter is positioned at an angle with respect the meter surface and the sweep hand indicator of the utility meter so that the sweep hand indicator is illuminated from an angle to provide a shadow of the sweep hand indicator. The photo detectors detect changes in the intensity of light reflected on the sweep hand indicator and the background surface as well as the shadow of the sweep hand indicator. The two photo diode detectors are electrically coupled in series but in opposite directions relative to an output node, so as to cancel each other at the output node in normal operation. The passing of the sweep hand indicator changes the signal produced of each of the photo diode detectors at the output node, independently but in opposite directions.