I am 64 and did not wear glasses until I was in my 40s....
Anyway, I am using a pair of bifocals that work terrific. The top lens is set so that 4 feet through 9 feet is in crisp focus, the bottom lens is set so tat 2.5 feet through 5 feet are in crisp focus. I can see the end rail on the table through the top lens, and I can see the CB and my tip with the bottom lens. Sometimes I have to move my head up or down to see some intermediate distances with the required crispness. The bottom lens occupies the bottom 50% of the lens (about 70% of the width, and the top lens is the other 50%, this is significantly higher than normal bifocal bottom lense placement..
If you do this, make sure the optician puts the "eye point" up high on the top lens so you are looking through the best corrected section when looking straight down the table.