I will split my answers into points for each paragraph.
1)Computer lenses usually allows for intermediate and near vision simultaneously, Distance/far vision will not be clear. It is counted as a Deskbound lens. Digital lenses are good for early presbyopes or individual who does alot of near work e.g. students/desk workers. They allow for distance, slight intermediate and near viewing at the same time but the intermediate zone is quite narrow. Thus If your Presbyopia or lao hua reach above a certain threshold, it doesnt work for you anymore as you are considered underpowered.
2)When you have presbyopia/laohua and you don't correct it, the solution for you to feel better when reading is either by removing your glasses to read OR to bring your reading material further from you. But if removing your glasses makes it worst then you might be far-sighted and requires progressives/digital/reading glasses for sure.
3)It usually sets in at about 37 years old onwards.
37-40 years old=+0.75--+1.00
41-47=+1.00--+1.75
47-50onwards=+1.75---+2.50
This is just a general indication and the reading power varies on individual eye muscles and their habitual working distance. Like you are presbyopic for both eyes, unlikely one. If its the case, likely your glasses degree is off after a period of time.
4)Sync 3 pro is a digital lens, thus you can refer to point 1.
dont know luff or cry liao now...
