PinholeGlassesCesar

For presbyopia, they help to focus and in my case I use them daily. They don't feel like the crystals leave a different view, with the grid bothering a bit. The advantage is that you can read without problems and without effort with them and after a while they are no longer necessary.
Be sure to consult your eye doctor.
It is a combination of previous creations from this site, I list them now:

https://www.thingiverse.com/thing:3663799
With those who could see better, he uses a hole diameter of 1 mm and the distance between them is 2 mm. Structurally they are very comfortable but to transpot them printed in PLA they break easily.

https://www.thingiverse.com/thing:3089350
This model was the one that I found more attractive simple to print and more resistant to transport in the backpack for example. Because of the distribution of the points I could not see with them so well.

https://www.thingiverse.com/thing:4362910
The author presents together with his model more technical