Mike,
You didn't give much information, so I'll do the best I can.
Since this is a handgun forum, I'll figure you probably have a handgun.
Your tri focals also tell me you may be over 40 years old.
I started out shooting wearing my multi vision glasses, and it worked for a while. Then I started to get severe eye strain, along with blurry/double vision after 15-20 minutes, and would have to stop.
A little detective work revealed my glasses were just a bit blurry at 36", where my front sight was. I had a pair of single vision computer glasses that were focused to 36", for my computer screen. This helped a lot.
The targets were a bit blurry at 7-15 yards, but the front sight focused fine. At 25 yards, targets were too out of focus to hit much, but at least I could shoot out to 15 yards.
I figure if home defense arises I may not be wearing any glasses at all. But, I also figure it will all happen well inside 5 yards, and will probably use combat sighting or point and shoot.
Two weeks ago, I had laser surgery to remove a cataract and correct astigmatism on my dominant eye. I haven't been to the range yet, but in between the blurriness of healing, I can clearly see the front sight and hundreds of yards beyond. The surgery is going to be a very satisfactory and permanent solution.
Hope I guessed right and gave you pertinent information.