I worked for Johnson & Johnson, when they developed the progressive "Definity" lenses. They sold out the eyeglass business to Essilor, who still makes the Definity. That was 12 or more years ago, but I still wear them. They are the best glasses, that I have ever worn. The range is better, for computer, or shooting. They are not cheap, but are worth every penny. If you are still wearing flat top bifocals, then you are missing out on what is possible, by wearing progressive lenses. Spend the money on the lenses, not the frames.