ROT: PHOROPTER

Today's random object is the device the eye doc uses while saying "Which looks clearer… number one or number two? Three or four?" or something along those lines. I shot it with my cell phone while waiting in my eye surgeons examination room. Everyone is familiar with this thing but I had never heard it's actual name before. I hate not knowing something which means I did some Googling. I found out it's called a Phoropter. Yep, I will probably never remember that. But hey, now you know too!