ah, no it's alright! i just assumed that eyeglass prescription was the same in all countries (just like lots of things that later turn out to be swedish only??), sorry. i still can't help laughing about it though. it's like the ō character. i know how it's supposed to be read and it's not even funny but i can't stop reading it as an ö since we sometimes write those as ō and the sound is so different and it cracks me up and i'm off track again sorry ;/