The distance between the lenses or bridge size is called what?

• A. Dbl
• B. Eyesize
• C. Lens Size
• D. A Measurement

Answer: (A)

The distance between the lenses is called the DBL, which stands for distance between lenses. It’s the bridge width—the measurement across the nose between the inner edges of the two lenses. This fit matters because it determines how the glasses sit on your nose and how the lenses align with your eyes.

For context, eyewear sizing typically uses three numbers: eye size (the width of one lens), DBL (the bridge width), and temple length (the arms). The eye size describes how wide each lens is; the DBL is not the same as eye size and isn’t just any generic measurement. A typical DBL ranges roughly from 14 to 22 mm, depending on frame style and patient facial structure.

So, the term that precisely names that space between the lenses is DBL.