Practice Test GeeksCOT - Certified Ophthalmic Technician Practice Test
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Optometry Flashcards

7 cards from real COT practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.

Read the first 7 Optometry flashcards as text

  1. Which contact lens parameter describes the curvature of the back surface of the lens and determines how it fits on the cornea?

    Answer: Base curve radius

    The base curve radius (BCR) defines the curvature of the posterior contact lens surface and is matched to corneal curvature for proper fit.

  2. A rigid gas-permeable (RGP) contact lens that is fit too steeply compared to the cornea will show which fluorescein pattern?

    Answer: Apical clearance (bull's-eye pattern)

    A steep-fitting RGP shows central fluorescein pooling (apical clearance) with peripheral edge seal, creating a bull's-eye appearance.

  3. The Snellen fraction 20/40 means the patient sees at 20 feet what a person with normal vision sees at:

    Answer: 40 feet

    The denominator in a Snellen fraction represents the distance at which a normal observer can resolve the same letter the patient resolves at the test distance (20 feet).

  4. A patient with 20/20 acuity complains of glare and halos at night after LASIK. These symptoms are most likely caused by:

    Answer: Ablation zone smaller than scotopic pupil diameter

    When the scotopic (night) pupil dilates beyond the laser ablation zone, untreated peripheral cornea causes optical aberrations including halos and glare.

  5. Which type of bifocal segment provides the widest near reading area?

    Answer: Executive (full-width) bifocal

    The executive (Franklin-style) bifocal occupies the full width of the lens, providing the largest near viewing area of any bifocal segment design.

  6. When prescribing prism for a patient with esophoria, the base direction should be:

    Answer: Base-out

    Base-out prism displaces images nasally, reducing the convergence demand and relieving the inward deviation of esophoria.

  7. A lensometer (lensmeter) is used to measure all of the following EXCEPT:

    Answer: Axial length of the eye

    A lensometer measures the optical properties of ophthalmic lenses (sphere, cylinder, axis, prism); axial length is measured by A-scan ultrasound or optical biometry.