The two perfect circles mounted on a wire frame were originally known as "teashades". They became hugely popular in the 1960's, led by Lennon's fondness for them. Other rockers like Mick Jagger and Jerry Garcia also sported them around the same time. Heavy Metal God Ozzy Osbourne can often be spotted wearing the circular spectacles to this day.
Personally though, when I think of teashades I think of John Lennon, and I know I'm not alone in that respect. The term John Lennon sunglasses is undisputeabely the phrase that is most often used to describe these sunglasses, so that's really ends any argument against it in its tracks.
The black and white photo of John Lennon standing cross-armed, wearing a "New York City" sleeveless t-shirt, and his sunglasses is perhaps the most popular still photo of Lennon. This portrait does its part to see Lennon's legend stays radiant and his sunglasses ever in demand.
When I was a teenager and just starting to experience the joys of Rock 'N Roll, and all the glorious things that came along with it, one of the first things I knew I needed to own to look the part was a pair of John Lennon sunglasses. Of course I wasn't the only guy to sport the rocker shades. They were just too darn popular among peace toting hippies like myself, so I didn't stand out much.
They are still my choice of concert shades and I always make sure I have a pair somewhere around the house. John Lennon sunglasses are here to stay.