An imaging system comprising: an optical sensor array including a plurality of sensor elements; an objective lens configured to direct light from a field of view onto the plurality of sensor elements; an active polarization filter positioned to filter the light en route to the optical sensor array, the active polarization filter being switchable electronically between first and second operational states, the active polarization filter providing unequal relative attenuance, in the first versus the second operational state, of nonparallel polarization components of the light; and logic configured to: switch the active polarization filter from the first operational state to the second operational state, and to compare a brightness response of the plurality of sensor elements in the first operational state of the active polarization filter to the brightness response of the plurality of sensor elements in the second operational state of the active polarization filter, wherein comparing the brightness responses comprises comparing brightness values of corresponding pixel elements of a first digital image and a second digital image, respectively acquired with the active polarization filter in the first operational state and with the active polarization filter in the second operational state; associate one or more pixel elements of the first digital image with electronic display content based on a difference in the brightness values of the one or more pixel elements of the first digital image relative to corresponding pixel elements of the second digital image; map one or more display screens onto a frame of reference of the imaging system based on locations of the one or more pixel elements associated with electronic display content; and establish sideband communication, between the imaging system and an electronic device equipped with a display screen of the one or more mapped display screens, enabling the electronic device to modulate display emission from the display screen to broadcast its identity to the imaging system. an optical sensor array including a plurality of sensor elements; an objective lens configured to direct light from a field of view onto the plurality of sensor elements; an active polarization filter positioned to filter the light en route to the optical sensor array, the active polarization filter being switchable electronically between first and second operational states, the active polarization filter providing unequal relative attenuance, in the first versus the second operational state, of nonparallel polarization components of the light; and logic configured to: switch the active polarization filter from the first operational state to the second operational state, and to compare a brightness response of the plurality of sensor elements in the first operational state of the active polarization filter to the brightness response of the plurality of sensor elements in the second operational state of the active polarization filter, wherein comparing the brightness responses comprises comparing brightness values of corresponding pixel elements of a first digital image and a second digital image, respectively acquired with the active polarization filter in the first operational state and with the active polarization filter in the second operational state; associate one or more pixel elements of the first digital image with electronic display content based on a difference in the brightness values of the one or more pixel elements of the first digital image relative to corresponding pixel elements of the second digital image; map one or more display screens onto a frame of reference of the imaging system based on locations of the one or more pixel elements associated with electronic display content; and establish sideband communication, between the imaging system and an electronic device equipped with a display screen of the one or more mapped display screens, enabling the electronic device to modulate display emission from the display screen to broadcast its identity to the imaging system. switch the active polarization filter from the first operational state to the second operational state, and to compare a brightness response of the plurality of sensor elements in the first operational state of the active polarization filter to the brightness response of the plurality of sensor elements in the second operational state of the active polarization filter, wherein comparing the brightness responses comprises comparing brightness values of corresponding pixel elements of a first digital image and a second digital image, respectively acquired with the active polarization filter in the first operational state and with the active polarization filter in the second operational state; associate one or more pixel elements of the first digital image with electronic display content based on a difference in the brightness values of the one or more pixel elements of the first digital image relative to corresponding pixel elements of the second digital image; map one or more display screens onto a frame of reference of the imaging system based on locations of the one or more pixel elements associated with electronic display content; and establish sideband communication, between the imaging system and an electronic device equipped with a display screen of the one or more mapped display screens, enabling the electronic device to modulate display emission from the display screen to broadcast its identity to the imaging system.