Check the response speed
characteristics of any load
to be controlled to be sure that the duration of the sensor's output
signal and the time between subsequent outputs are sufficient to allow the load to react properly.
If the load is too slow to react, a delay timer may be required between the sensor output circuitry and the load to extend the duration of the sensor's output signal.
A better solution involves changing how the sensor is mounted and what part of the object it's sensing (the sensing geometry) in order to equalize the duration of the light and the dark times.