Question for either an optician or physicist who knows about optics...

[YinuCeatleAyru]

My eyesight has been getting gradually worse and I was just getting to the point that I thought I really need an opticians appointment just when lockdown happened. I will obviously go and see an optician as soon as possible (which may be a while as family members are vulnerable) but in the meantime I am struggling a bit with focusing on text.

As a temporary solution I realised that I could order reading glasses for £5 along with my click & collect grocery shop - of course I had no idea what strength to order so I picked "2.5" whatever that means.

Obviously 2.5 was wrong, but what I find is that if I hold these 2.5 glasses about half way between my eyes and my computer screen, the blurry text comes into sharp focus through the lenses. Any closer (e.g. on my nose) or further away, and I still see a blur.

Can anyone work out from that information whether I need lenses that are stronger or less strong than 2.5 and recommend a different strength to order when I next manage to get a click&collect?

With reading glasses you are not supposed to read right up close. If, while you are wearing the glasses, you hold the book or document at a slight distance (about half an arms length) you will see better. That clear spot is the focal point if the lenses, the point where the image will sharpest, so that's where you hold the thing you are reading.

Try it and let us know whether it works.

You might be best using a home reading glasses test, something like this, although I havnt tested this one.
I think there are ones you can use on a computer screen if you cant print - Google is your friend.

Firstly do you wear any correction for distance? How old are you?
+2.50 is going to be too strong if you are under 55 and have no hyperopic distance prescription.

Try 1.0 to start with. If you've only just started to notice blurring you won't have lost that much muscle strength. Keep the 2.5s though - you'll need them in a few years.

thanks for the various ideas. I tried the home vision test before picking 2.5 but it didn't seem helpful as all the different text sizes were blurry and obviously I could read the larger ones more easily as the blurs were more recognisably the shape of letters but that didn't tell me what correction I needed to get rid of blurs as there were no non-blurry lines. the blurriness seems the same whatever distance I hold the text from my eyes so normal for me is about 30-35cm for book or phone and about 50cm for pc screen - putting my head closer doesn't help.

but it's not the same all day, it is much better now than it was this morning when I posted and it's like that each day, worse in the morning and ok by evening - no blurs at all right now. I don't have any glasses now but have had eye tests every 2-3 years which up till the last one (3 years ago) regularly concluded that my vision was mostly fine but slightly borderline approaching the need for specs. (I am mid 40s). come to think of it I always had those eye tests in an evening after work so probably if I did the same now I would be told my eyes are fine still.