I got the Johnson and Johnson Vision but I don't know what Diopters 15.0D means. Thanks for your help.
Assuming you had your vision corrected to see distance it would suggest you were likely about -3.0 short sighted or myopic before you had your surgery. IOL powers do not match the eyeglass powers. They typically go from a lower end of about +5D which is for myopia, to +30D which is for someone that is far sighted. A power of about +19 D is for someone that needed no correction prior to surgery.
I am assuming your are referring to the lens power of the IOL that will be replacing your natural lens that will be removed.
This power is calculated using a few factors, such as axial length. To keep it in simple terms, this is strictly your distance power correction you need to focus the incoming light so that you obtain 20/20 or your best vision at distance (assuming that is the goal you are trying to achieve). It does not address Astigmatism. IOls typically come in steps of 0.5D and you pick the power that gets you closest to Plano or -.25 D as you don’t want to go into the hyperopia side.
If interested you can google cataract lens power calculations and see the various formulas and adjustments made to determine lens power.
I have an astigmatism I was told and the Dr said he couldn’t guarantee me that I would not need glasses to see for distance.
They can never guaranty as for one thing they can miss the refractive mark. Also astigmatism can cause issue. There actual has to be a certain amount of astigmatism before they can use a Toric IOL to correct for Astigmatism. How much is your Astigmatism and did you get a Toric IOL?
And even with a Toric IOL there will probably be residual Astigmatism. One final point is they can only correct for regular astigmatism. Irregular Astigmatism is not correctable, as far as I aware.
I am not sure how much my astigmatism is. And I just got the basic lens so I can see without glasses for distance. It is free for me except for the special measurement test and for the dropless surgery. Anything more then that would cost me a lot more and I couldn’t afford it.
2months+ after the cataract surgery get a regular eye exam at an optometrist to get your eyeglasses Rx that will tell you how much astigmatism (cylinder value in diopters) you now have in that eye as well as how close they got for power (sphere value in diopters) for nearsighted vs farsighted.
A cylinder value less than 1.0D would mean very little astigmatism and won’t affect vision very much.
Thanks 