Eye Health Exams & Procedures Gallery of Eye Examination Equipment By Troy Bedinghaus, OD Troy Bedinghaus, OD LinkedIn Troy L. Bedinghaus, OD, board-certified optometric physician, owns Lakewood Family Eye Care in Florida. He is an active member of the American Optometric Association. Learn about our editorial process Updated on January 22, 2020 Medically reviewed by Johnstone M. Kim, MD Medically reviewed by Johnstone M. Kim, MD on January 18, 2020 Johnstone M. Kim, MD, is a board-certified ophthalmologist and a practicing physician at Midwest Retina in Dublin, Ohio. Learn about our Medical Review Board Print If you have never had a comprehensive eye examination, you may be surprised at the number of tests your eye doctor will perform. A complete eye exam involves the use of many pieces of equipment and several instruments. Here is the most commonly-used equipment. Exam Room Westend61 / Getty Images An examination room at an eye doctor's office usually consists of an exam chair, a phoropter, an eye chart, a slit lamp and a stool for the eye care practitioner. Retinal Camera leezsnow / Getty Images A retinal camera is used to photograph the back of the eye, including the retina. It is used to document eye diseases. The camera produces a bright flash when a picture is taken. The Anatomy and Function of the Retina Phoropter PaulVinten / Getty Images A phoropter (or phoroptor) is an instrument used during an eye examination to measure refractive error and determine eyeglass prescriptions. Typically, the patient sits behind the phoropter and looks through it at an eye chart. The optometrist then changes lenses and other settings, while asking the patient for feedback on which settings give the best vision. Binocular Indirect Ophthalmoscope U.S. Air Force photo/Staff Sgt. Victoria Sneed An ophthalmoscope is an instrument used for examining the interior structures of the eye, especially the retina, consisting of a mirror that reflects light into the eye and a central hole through which the eye is examined. A binocular indirect ophthalmoscope (BIO) is worn on an eye doctor's head in order to have the use of both hands to examine the eyes. Manual Keratometer Troy Bedinghaus A manual keratometer is used to determine how flat or steep the cornea is. It is often used to measure and diagnose conditions such as astigmatism, keratoconus, corneal scarring and corneal distortion. A keratometer is commonly used to fit contact lenses as well. Anatomy and Function of the Cornea Autorefractor SerafinoMozzo / Getty Images An autorefractor is a machine used to measure a person's refractive error and prescription for eyeglasses or contact lenses. This is achieved by measuring how light is changed as it enters a person's eye. The automated refraction technique is quick, simple and painless. The patient takes a seat and places their chin on a rest. One eye at a time, they look into the machine at a picture inside. The picture moves in and out of focus as the machine takes readings to determine when the image is on the retina. Several readings are taken which the machine averages to form a prescription. No feedback is required from the patient during this process. Slit Lamp Stefan Kiefer / Getty Images A slit lamp is a microscope with a light attached that allows the doctor to closely examine the eye. This instrument is used to view the structures of the eye such as the cornea, iris, and lens. With special lenses, it is possible to examine the back of the eye as well. A slit lamp allows the practitioner to have an amazing view of the inside of your eyes. Tonometer Arthur Tilley / Getty Images A tonometer is used to measure the pressure of the eye. The test is used to help detect glaucoma. Numbing drops are used for the type of tonometer that actually touches the eye. Some doctors use the air-puff tonometer in which no numbing drops are needed. A tonometer measures the production of aqueous humor, the liquid found inside the eye, and the rate at which it drains into the tissue surrounding the cornea. Lensometer Ohio Air National Guard/Staff Sgt. John Wilkes A lensometer is an instrument used to measure the power of an existing lens. An optician uses a lensometer to determine the prescription of a patient's eyeglasses. Retinoscope and Direct Ophthalmoscope photo by ARZTSAMUI / Getty Images A retinoscope is used to shine light into a patient's eye for an eye doctor to observe the reflection off the retina. The light is moved back and forth across the pupil A retinoscope is especially useful in prescribing corrective lenses for patients who are unable to give oral feedback to the eye doctor. It is also useful for determining how well the eyes work together (accommodate) to see clearly. A direct ophthalmoscope is a hand-held instrument used for examining the interior structures of the eye, especially the retina. It consists of a mirror that reflects light into the eye and a central hole through which the eye is examined. Was this page helpful? Thanks for your feedback! Sign up for our Health Tip of the Day newsletter, and receive daily tips that will help you live your healthiest life. Sign Up You're in! Thank you, {{form.email}}, for signing up. There was an error. Please try again. What are your concerns? Other Inaccurate Hard to Understand Submit Article Sources Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy. American Optometric Association. Comprehensive Eye and Vision Examination.