Sometimes graphic designers can muck up the look of a mark. Take this one, for example:
I am reasonably certain that this is meant to be the sunglass version of the regular Xperio lens. Indeed, looking at the company's website confirms this guess. But something about the squishing of the UV onto the core Xperio mark bothers me. In fact, the website only exacerbates this confusion, as it contains two different logos for the XperioUV mark, and then shows the mark in text as you see in the bottom of the ad above, as two separate words.
Every trademark lawyer and marketer has a different view, but I think that since "UV" is merely a descriptor to indicate sun protection, why bother making a fancy logo and gluing UV onto Xperio to try to make a new mark? "UV" is generic, and Xperio is so distinctive. Why not merely let UV function as generic, rather than trying to gin up a new trademark with it? It's just line extension - so you'd have Xperio UV, Xperio Bifocal, Xperio Progressive, Xperio reading, as needed. But no one asked me ...
This has been your trip into the mind of a trademark lawyer. Trust me, it's no easier on this end.