Sensors that operate based on the time-of-flight measurement concept measure the interval of time that passes between the transmission of a light pulse and the receipt of the light signal reflected by the object. They then use the measured interval to calculate the distance between the sensor and the object. Because the light is propagated along its path at a constant speed, the time-of-flight is proportional to the distance traveled. A major benefit of time-of-flight measurement is that the measurement result is only slightly influenced by the type of object surface involved.
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