Optician/Optometrists: What are these marks left by a lensometer on my glasses?

<p>I went to the optometrist today and he took my existing sunglasses and measured the prescription on them with a machine (I assume it was a lensometer)?. Well, I got my glasses back and a bit later in the day noticed these small patterns on the lenses. There are 4 of them total, 2 on each lens of the glasses. Each pattern is the same: A circle with a straight horizontal line underneath the circle… kind of like:</p>

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<p>They look sort of like scratches, and I can’t wipe them away. I am going to call the optometrist at the next opportunity I get (but they are closed until after the weekend), but I really want to know what these are . does anyone know? They certainly aren’t bifocal glasses!</p>