Varifocal blurred areas and non-centred focus

[els]

Can anyone tell me why do varifocals all have blurry areas to the bottom left and right? Why can't those bits be in focus for near vision the same as the central area?

Also, I have no prescription in my right lens as that eye is too poor. My left eye is fine but it does all the work. In my left lens, the near-vision, focused area is slightly to the right, so I have to move my head sideways to get focus. Assuming that lenses can only have a narrow near-vision focused area (?), could lenses be made with the focused area in the centre?

My optician is getting me new lenses (Zeiss this time) as the first set haven't worked out after 3 weeks of trying, but they didn't seem to answer these questions for me - so any info will be much appreciated. Please note - I don't speak "optician", I'm just a consumer! Thank you very much.

[Steve Machol]

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