Terminal with flicker-corrected aimer and alternating illumination

Abstract

An indicia reading terminal is disclosed that eliminates unwanted flickering effects in an illuminated screen reading mode, among other advantageous features. The indicia reading terminal, in response to a screen reading signal, is operative to activate a screen reading cycle. In the screen reading cycle, an imaging subsystem is activated at least once at the same time that an illumination subsystem is activated for one of a plurality of active illumination periods, for a first illuminated exposure period. The imaging subsystem is activated at least once while the illumination subsystem is not activated, for a first unilluminated exposure period, which is longer than the first illuminated exposure period. An aimer subsystem is activated for a plurality of active aimer periods when neither the imaging subsystem or the illumination subsystem is activated, wherein intervals of time between the active aimer periods are equal, within nominal tolerances.