Optics

Seeing eye to eye

Not a lot of robots are equipped with optical sensors. As it happens, sight is not as prevalent in autonomous artificial lifeforms as it is in organic ones. They have access to a wider array of senses, including heat, electricity, and air displacement for example, which are all far more powerful and less error prone to assess the environment. This in turn make eye-bearing robots all the more terrifying.

Origin of optics

In the early days of robotics, optics were a given: all animals have eyes, so why automaton wouldn't? It made them more familiar, reduced their inherent uncanniness. Then, when familiarity was not the main factor in play, high-end optics were installed on manned drones, to give visual feedback to the operator. Humans were still more comfortable with their vision, despite the range of new senses at hands. Finally, when robots were fully automated, they were striped of all unnecessary or redundant captors, including optics.

The only reason some warbots were still equipped with glowing eyes was to strike fear and upset their foe.