What is the power of Intermediate and Reading?
I would like to learn the differences of these two prescriptions:
Sphere Add Distance(?) Intermediate(?) and reading (?)
OD +0.50 +2.50
OS +0.50 +2.50
OD +0.75 +2.25
OS +0.75 +2.25
What are the power for Distance, Intermediate, and reading (separately)?
For the computer monitor 27 inch (2.5 -3 feet distance) I wear single vision +1.25 - +1.50,
Laptop 17 inch (2 ft distance), single vision + 1.50 - + 1.75
Book (12 - 14 inch distance), single vision + 1.75 - +2.00
And it’s interesting that mostly the pd measurement results are different at different optometry?
31.5 / 29, 31.5 / 29.5, 31/29.5, 31/29
The progressive Lens, comparing between Shamir III and Newest Varilux X 4D. Which one I should get ?
The intermediate diopter is usually the diopter between the far diopter and close vision diopter, the one that allows you to see best at 1-2 meters.
The example you showed is ok I think, if you have +0.75 far vision and 2.25 addition, that means you close vision diopter is +3.00, so intermediate diopter is 1.50-1.75.
The difference between the two prescriptions is the far distance diopter +0.50 at the first, and +0.75 at the second because at the second the addition is smaller, the close vision diopter is the same on both prescriptions +3.00.
So the far vision diopter is +0.50, intermediate diopter should be +1.50 or +1.75, and close vision diopter is +3.00. I say it should be because it depends on your comfort.
About the pupillary distance, the difference between the values are small (0.5 mm), it does not affect your vision, only the big differences between values, for example, 31 and 33. 0.5 mm is really ok. Depends on how it is measured (ruler or digitally), but both ways work fine.
About the lens type, the experience is different from person to person, so if you already had one of them and it was satisfactory for you stick with it, if this is your first lens, look at the characteristics, and choose which is closer to your needs, because as quality, they are both good lenses.
I like more Essilor, but this is a personal opinion backed up by 15 years of experience with this lenses.
Hope this helps