I have a commercially-made magnifying glass with LED illumination, but it's not bright enough and it eats batteries. So I made a new magnifying glass that fixes those problems.
This is sort of a sequel to my Instructable: https://www.instructables.com/id/Ultra-Bright-24-LED-Lighted-Magnifier/
That Instructable described a lighted magnifier that runs on AC power, to get maximum brightness without worrying about charging or changing batteries. I use that magnifier all the time. In fact, I've made three of them, and keep one in each of my work areas. But sometimes I really need the portability of a battery-powered magnifier.
This new magnifying glass has a bright array of 15 LEDs producing 37500 mcd. It has an optical glass lens with about 3.5x magnification. The handle was made on a CNC machine from European beech hardwood.
And it has a power supply using four lithium cells to provide years and years of regular use without having to think about the batteries! (If I use it every other day, keeping the light on for a full minute every time I use it, the batteries will last more than six years.)
I made it at TechShop. http://techshop.ws/