Optical detector arrangement for document acceptor

摘要

A sensor arrangement for a banknote validator or other document acceptor using optical transmissive measurements includes at least one light source located on a first side of a document path and arranged to transmit light around the document path to a second side of the document path, the second side being opposite the first side. Optical detectors are located on the first side of the document path and arranged to receive light sent from the light source and passing through the document transport path.

主权项

1. A sensor arrangement for a document acceptor using optical transmissive measurements, the sensor arrangement comprising:
at least one light source located on a first side of a document path and arranged to transmit light around the document path to a second side of the document path, the second side being opposite the first side; one or more optical detectors located on the first side of the document path and arranged to receive light sent from the light source and passing through the document path; and a light pipe assembly located on the second side of the document path adapted to receive light from the at least one light source located on the first side of the document path and transmit light through the document path to the one or more optical detectors, the at least one light source is arranged such that, when a document is in the document path, light transmitted by the light source to the second side of the document path reaches the second side of the document path substantially without passing through the document; wherein the light pipe assembly includes a plurality of surface features with substantially trapezoidal bases.