An electronic vertical angle sensing and indicating device for use on
aiming systems is provided for bow sights and for other aiming sights for
projectile launchers. Improved vertical level measurement and display
minimizes the left-right drift of a projectile by sensing and indicating
to the user when the projectile launcher is tilted slightly prior to
release of the projectile. The vertical level indicator is easily viewed
within the field of direct or near direct vision and focus of the eye in
a reduced profile that does not distract the operator from the task of
accurately aiming the projectile is provided. One embodiment of the
present invention positions the signal indicators in the far-field of
view of the eye, so that all of the signal indicators, the sighting means
and the distant target being viewed are simultaneously in focus or
near-focus.