https://www.cnet.com/roadshow/news/gentex-smart-rearview-mirror-iris-scanning/

Until I get on the road with this tech, I can only say that the static demo of it seemed like a faster, more cohesive way of knowing what lurks where you can't see. 

A recent AAA Foundation survey found that some 30 percent of drivers now rely solely on blind-spot monitoring tech when they make all or many of their lane changes. That's disturbing given that today's blind-spot tech usually consists of a couple of blinking LEDs and disembodied beeps that urge you to turn your head and figure out what the sensor just spotted. A recent study of the effectivenes of blind-spot monitoring tech found it reduces lane-change crash involvement by 14 percent in cars that have it, but that seems a far cry from what it could do if it were an automatic video system.