American Board of Opticianry (ABO) Practice Test 2026 – The All-in-One Guide to Master the American Board of Opticianry Exam!

The purpose of a lensmeter is to measure the prescription of lenses. This instrument is essential in optometry and optical labs for determining the optical power of prescription glasses and contact lenses. A lensmeter can accurately identify the sphere, cylinder, and axis of the lenses, which are critical parameters necessary for providing the correct vision correction for a patient.

When using a lensmeter, the technician places the lens in the device, and by looking through the eyepiece, they can read the values that correspond with the optical characteristics of the lens. This information is vital for ensuring that lenses are made to the correct specifications required by the wearer.

Other choices do not align with the primary function of a lensmeter. Adjusting frame fit pertains to the physical alignment and comfort of eyewear, while testing lens durability involves assessing how well lenses can withstand various forms of stress or impact. Calculating the base curve of a lens, although relevant to lens design, is a different aspect and not the primary function of a lensmeter. Therefore, the primary and correct use of a lensmeter is indeed to measure the prescription of lenses.