hmmm, fyi, jb city square is currently undergoing renovation, thus i suggest you may consider going sometime in the second half of the year.
The shop name is Eye Optic Vision. Currently it is temporarily shifted to a smaller shop on the 2nd or 3rd level i think, so the range is not that much to browse for the moment until at least july/august when they re-shift to a bigger store.
I will revisit the store again likely end of the year when i suspect more new frames will come in for the xmas/new year festive season. They have brands like masaki, pro design, urband, eyelet, EyeDC etc. I always like to visit them as the sales ple are friendly and i can good prices, esp when the sg dollar is stronger.