The Lensometer, also known as a Focimeter, is a diagnostic device used to measure the optical power and prescription of eyeglass lenses. It helps eye care professionals verify existing prescriptions, detect lens alignment issues, and ensure accurate lens fitting before dispensing glasses to patients. It is commonly used in ophthalmology clinics, optometry practices, and optical laboratories.

It is typically made of a durable metal and high-grade plastic body with precision glass optics and internal electronic components.