6/1/2023 0 Comments Spectacle prescription meaningIt's a measurement every place needs in order to make prescription lenses. If you don't see your PD on your prescription, we suggest calling the last place that made your glasses. Luckily, unlike your prescription a PD doesn't change after you stop growing, so a measurement from years ago will still be accurate. It is also for this reason that you should strive for an accurate PD measurement rather than guessing it. Take Tyler's word for it-it truly is unwanted. You want the OC to be as close as possible to the center of your pupil to avoid something called prismatic imbalance or unwanted prism. It's the point of the lens where the most light converges and therefore the clearest part of the lens. Your PD is a necessary measurement when you buy from SportRx because of something called the OC or ocular center. Near is a slightly different number used for reading, so you don't need to worry about it. If you see "Dist" on your prescription, that's short for "Distance" and is the number we need. PD is the abbreviation for "pupil distance." It's the distance between your pupils (binocular PD), or the distance from each pupil to the center of your nose bridge (monocular PD), written in millimeters. Naturally, our SportRx lab is one of those. However, there are specialty labs which can. Over a 2 is getting into the strong range and can limit your frame options when shopping for glasses.Īccording to Tyler, most labs can handle up to a 3 in CYL correction but not much beyond that. As with the SPH correction, a higher CYL number means a stronger astigmatism. It being positive or negative doesn't make a difference the number itself is more important. It doesn't fall under either nearsightedness or farsightedness, though it can make your vision appear blurry.Ī CYL correction is easy to correct for and can be written as either a + or - depending on who wrote your prescription. Astigmatism is a very common condition and simply means your eye isn't perfectly round. ![]() In short, CYL means you have an astigmatism. This correction builds off the SPH correction we discussed above and is only present in a specific axis of the lens. These are all the basic elements that may appear on a glasses prescription, but for more details on how to read your prescription, keep going!Ĭylinder, or CYL, refers to a type of correction your eye needs in a certain direction, or axis. You'll see these on contact lens prescriptions.
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