So, today I needed to clean my laser lens. So I first tried cleaning it with a gas duster. Bad idea. It left some nasty residue on it, and now it wont come off. So I got a micro fiber cloth, and put some 70% isopropyl alcohol on it. Well, the residue is sorta gone, but now there is this noticeable line on the laser point. And I can't get rid of it. Did I scratch the lens? What is the proper way to clean it then? I did search the forum, and I found so many mixed answers.