Abstract: A light collector and prism that collects light from a single bulb and produces a narrow strip light beam is disclosed. The light collector and prism is formed of an elongate, integral piece of transparent material (plastic) and includes a light collecting section at one end and a prism section at the other end. Light rays emitted from a small bulb positioned in an aperture in the light collecting section are collected, to some extent (e.g., imperfectly) collimated, and directed into the prism section. The prism section extends outwardly from the collector section so as to receive the light rays collected, collimated and directed by the collecting section. The prism section includes a plurality of prism surfaces located along one edge thereof. Light rays directed by the light collecting section toward the prism section are reflected by the prism surfaces toward an opposing, narrow, light emitting edge of the prism section. Light rays emitted from the narrow edge form a narrow strip light beam.

Abstract: A wide range current flow fault detector comprising a current sensor and a selective interrogator are disclosed. Current flow, or the lack thereof, between a power supply (e.g., capacitor bank) and a load (e.g, the hammer coils of a line printer) is sensed by a current sensor connected to detect the voltages at spaced points along a selected length of the supply conductor connecting the power supply to the load. A differential amplifier forming a part of the current sensor produces an output voltage related to the voltage difference between the selected points. The output voltage of the differential amplifier is compared, in a comparator, with a preset voltage. Any time the output voltage of the differential amplifier is above the preset voltage, the output of the comparator changes from a first state (e.g., low) to a second state (e.g., high). At all other times, the output of the comparator remains in the first state.