With an exclusive three-part blog series, we’ll be revealing some of Luxo’s most commonly asked questions regarding magnification. Our initial installment will focus on understanding the diopter and what it means for your application. You’ve heard the term, but what exactly is a diopter?
A diopter is the measurement used to determine the optical power of a lens, which is equal to the reciprocal of the focal length measured in meters. In simple terms, this means that each diopter increases the size of the viewed object by 25% at full focal length from the lens, as illustrated in the chart below.
Common Diopter/Power Relationships
Diopter |
Power |
% Bigger than Object |
Focal Length |
3 |
1.75X |
75% |
13” |
4 |
2.00X |
100% |
10” |
5 |
2.25X |
125% |
8” |
A diopter higher than 5D can be achieved through add-on accessory lenses. However, as diopter increases so does magnification, and working distance is reduced. So at 13D, magnification is at 4.25X but working distance is reduced to just 3”. For this reason, it’s best to use a microscope when working above 4X magnification.
With more than 60 standard and ESD-safe options to choose from, we carry a complete range of Luxo magnifiers and accessories to meet your specific requirements. Shop with us and save on the perfect magnifier for your application.