Certified Paraoptometric (CPO) Practice Exam 2025

What is the instrument used for manual refracting called?

1. Phoropter

2. Tonometer

3. Keratometer

4. Retinoscope

The correct answer is: Phoropter

The instrument used for manual refracting is known as a phoropter. This device allows the eye care professional to determine an individual's refractive error by presenting a series of lenses in front of the patient's eyes. The phoropter can help in assessing various aspects of the patient's vision, including the need for corrective lenses and the appropriate lens prescription. The other instruments listed serve different purposes in the field of eye care. A tonometer is designed for measuring intraocular pressure to help diagnose glaucoma. A keratometer measures the curvature of the cornea, providing information vital for contact lens fitting and evaluating certain corneal conditions. A retinoscope is used for evaluating the refractive status of the eye by observing the reflection of light off the retina, assisting in determining a rough estimate of the prescription before fine-tuning it with a phoropter. Each of these tools plays a critical role, but the phoropter is specifically the one associated with manual refracting.