Liquid drop image sensor

A liquid drop images sensor for determining the volume of liquid drops comprises a light source and an array of optical sensors which receive light energy from the source. The array is positioned relative to the source to establish a passageway therebetween through which drops can fall. Electronic structure connected to the array sequentially activates the array for discrete episodes during the passage of a drop through the passageway. The electronic structure also generates signals which indicate the proportion of the array affected by the shadow of the drop during each episode. Additionally, the liquid drop image sensor includes structure which accumulates the signals and uses them to calculate the volume of the liquid drop.