Video Transcript:
If you've ever needed reading glasses, you kind of know what reading glasses are used for. That's built into the name. Even so, you're using reading glasses to read. Now, what happens is in low vision, you lose your central acuity. So, you might you might be familiar with the term 2020, or if you're not in the US at 66 for the meters.
But, what happens with low vision is, oftentimes your central ability to have 2020 vision, to have perfect vision is impaired to the point that you can't achieve 2020 even with the the most powerful glasses there are. So that is where high powered readers come in. Because if you think about 2020, what 2020 is, is that's a 20ft.
And normally there's a there's a secondary test for reading that's performed at around, between 12 and 16in the to assess your reading acuity. So your reading acuity at that distance of 16in is how they measure that. Now, once you can't get to 2020 anymore, now maybe you can only get to 2040 or 2060. So when you get to that level of acuity, you're not really able to hold things at that far distance anymore and still be able to see it clearly.
That is where high powered readers become potentially helpful for different tasks. So what a high powered reader is, is kind of beyond the normal range of, of of just the normal range of reading prescriptions. And what you're doing with that is you are shortening the distance and increasing the size of what you're seeing.
So you're holding the reading material closer and having a pair of glasses that matches that closer focal distance. Now what you would do is over time. So when you have kind of early, super early stage low vision, you might not need the highest power reader. So we make these in a power. So if you're familiar with normal reading glass powers it goes like 1 to 3.
We make, high powered readers anywhere from like a plus four up to a plus 48. So a plus 40. It's ridiculously strong. And what those numbers are is I hate to get too mathy, but basically the the length, the focal length of the lens is one fourth for a four diopter and then 1/48 of a meter for a 48 diopter.
So what's 1/48 of a meter? That's a little bit more than two centimeters. So on a 48 diopter high powered reader, you would be holding that reading material about two centimeters from your face. Now, if you think about that in the context of what you might want to do with that high powered reader, you're probably not going to be reading a book.
But if you need to maybe examine the, maybe just detect like what pill bottle you have or like just read the fine print on something in the newspaper. Like for some reason it would be kind of for spot reading. Like you wouldn't sit and read a book now with a plus four, where the focal length is one fourth of a meter, or a plus five where it's one fifth of a meter.
So 20cm or 25cm, you could do things more comfortably. So you could possibly read a book. You could possibly, you know, read a newspaper, that sort of thing. So that is what high powered readers do and what they're for.
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Disclaimer: The information provided in this video is for educational purposes only and is based on our experience in optical solutions. We are not medical doctors. Consult with your ophthalmologist, neurologist, or other qualified healthcare professional before making any changes to your treatment plan. The solutions discussed are intended to support, not replace, professional medical advice.