Abstract: An apparatus and method for sorting documents is provided. A document transport on the apparatus conveys documents along a selected path of movement from an input bin to a series of output bins. An optical scanner, such as a video camera, is positioned along the selected path to capture images of the documents. The captured images are displayed on a display monitor to permit an operator to inspect portions of the documents for a desired characteristic. The operator activates a push button on a selector switch depending on the presence of the desired characteristic. Bins are provided for stacking and separating documents having the desired characteristic from those documents lacking the desired characteristic. Gates are provided for directing the documents to the appropriate output bin.

Abstract: A candling system for a mail extraction device incorporates a light source in the form of a light emitting diode and a cooperating photo-transistor detector which operate in the infrared range, to increase the system's immunity to environmental variations, and a linearization circuit for increasing the differentials in voltage which are developed between adjacent density levels (relative to the number of sheets involved), to permit the system to better monitor (distinguish between) envelopes containing an increased number of documents with improved accuracy and efficiency.