Tri-state detector for detecting types of light

Abstract

Provided herein are devices, systems, methods and various means, including those related to printer systems and, more particularly, relate to methods, apparatuses, systems and other means for monitoring a printer ribbon. Some embodiments use a multi-element detector, which is configured to detect a particular type of light emitted from a light emitter. The multi-state detector can include two sensors, one of which includes a polarizer filter that blocks polarized light. Embodiments can be used to determine, among other things, whether or not a printer ribbon is installed in a printer without the use of a snap plate.

Dependencies are inferred from the claim text.