Reticle:
a network of fine lines, dots, cross hairs, or wires in the focal plane of the eyepiece of an optical instrument [Vocabulary.com]
Noted in “All About The XM157 Next Generation Fire Control System for the XM5 Rifle,” Jennifer Sensiba, The Truth About Guns:
Fortunately, Vortex thought about that and made sure to design an optic that’s actually an optic, not a digital screen. The “smart” parts only project information (including a self-adjusting reticle) onto a transparent display inside of a normal low-power 1-8×30 variable optic (LPVO) with an etched reticle. If the smart parts fail, a soldier can still use the XM157 like a normal optic and stay in the fight without needing to switch to irons.
