CPOT Optical Dispensing & Lens Technology Flashcards

A patient's prescription reads +3.00 sphere. This patient is corrected for:

Answer: Hyperopia (farsightedness)

A plus sphere power corrects hyperopia by adding converging power to focus light on the retina for a farsighted eye.

Polycarbonate lenses are often recommended for children and safety eyewear primarily because of their:

Answer: Impact resistance and lightweight nature

Polycarbonate is highly impact-resistant and lightweight, meeting ANSI Z87.1 safety standards, making it ideal for children and occupational eyewear.

When verifying a finished pair of glasses with a lensometer, the technician is checking for:

Answer: Lens power, axis, prism, and optical center placement

The lensometer (focimeter) measures the sphere and cylinder power, axis orientation, prismatic effect, and optical center location of finished lenses.

UV-absorbing lenses help protect the eye from solar radiation that can contribute to:

Answer: Cataracts and macular degeneration

Chronic UV exposure is a known risk factor for both cortical cataracts and age-related macular degeneration, making UV protection a key dispensing recommendation.

Photochromic lenses darken when exposed to UV radiation because they contain:

Answer: Photosensitive molecules such as silver halides or organic compounds

Photochromic lenses contain photosensitive compounds that undergo a reversible chemical reaction upon UV exposure, causing the lens to darken.

Prism in ophthalmic lenses is measured in units called:

Answer: Prism diopters (Δ)

Prism power is measured in prism diopters (symbol Δ), where 1 prism diopter displaces an image 1 cm at a distance of 1 meter.