Reflector and anti-fog film in an optical sensor system

摘要

A dispensed product detection system and method for use in a refrigerated vending machine utilizing an optical light beam crossing the path through which a dispensed product travels. An optical emitter transmits a light beam through at least one layer of substantially transparent anti-fog film to reduce moisture condensation and across the product path to an optical detector wherein signal intensity is measured. As a dispensed product passes through the light beam between the emitter and the detector, the beam is momentarily broken, resulting in a change in signal intensity at the infrared detector which is registered as the vend of a product.