Terminal with flicker-corrected aimer and alternating illumination

An indicia reading terminal comprising:

• an illumination subsystem operative for projecting an illumination pattern;
• an aimer subsystem operative for projecting an aiming pattern;
• an imaging subsystem comprising an image sensor array and an imaging optics assembly operative for focusing an image onto the image sensor array;
• a housing encapsulating the illumination subsystem, the aimer subsystem, and the imaging subsystem;
• a memory capable of storing frames of image data representing light incident on the image sensor array;
• and
• a processor operative for addressing said memory, wherein said processor is operative to attempt to decode a decodable indicia represented in at least one of the frames of image data;
• wherein the indicia reading terminal, in response to a screen reading signal, is operative to activate a screen reading cycle, wherein:
• the imaging subsystem is activated to acquire frames of image data at least once at the same time that the illumination subsystem is activated for one of a plurality of active illumination periods, for a first illuminated exposure period;
• the imaging subsystem is activated to acquire frames of image data at least once while the indicia reading terminal does not project illumination, for a first unilluminated exposure period, which is longer than the first illuminated exposure period;
• and
• the 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.