Patent ID: 8046100

Claim:
A vending system comprising: an optical monitoring system to determine if a product associated with a customer ordering event is delivered to a receiving location, wherein the optical monitoring system comprises a plurality of light emitters and a corresponding plurality of light detectors disposed a substantially fixed distance from the plurality of light emitters, wherein a spacing between each of the light emitters is selected to minimize an effect of ambient and reflective light on the optical monitoring system, and wherein delivery of the product is determined by (a) separately activating then deactivating each of the light emitters such that all of the light emitters are individually activated in round-robin fashion and such that all of the light emitters are activated at least once during a period shorter than a time required for the product to fall between the light emitters and the light detectors, and (b) for each of the light emitters when that light emitter is activated, monitoring at least two of the light detectors, wherein the same at least two light detectors are monitored each and every time the respective light emitter is activated and wherein a product delivery is indicated in response to any of the at least two light detectors failing to detect light emitted by the activated emitter.