For opticians preparing for certification
Practice questions with worked math, timed mock exams, flashcards and hands-on instrument trainers for spectacle and contact lens opticianry. No account needed: your progress stays in this browser.
Counted from the question bank, flashcard decks, lessons and labs on this site.
Ophthalmic optics
Transpose −1.00 −0.75 × 180 to plus-cylinder form.
Sphere −1.00 + (−0.75) = −1.75. The cylinder changes sign to +0.75, and the axis moves 90° to 090. Answer: −1.75 +0.75 × 090. It is the same lens, written in the other form.
The ABO covers spectacle dispensing and the NCLE covers contact lenses. Every question, card and tool here is tagged with the exam it serves.
National Opticianry Competency Examination (NOCE)
The spectacle dispensing certification: ophthalmic optics, lens and frame products, measurements and fitting, ocular anatomy and the ANSI Z80.1 standards.
Contact Lens Registry Examination (CLRE)
The contact lens certification: corneal anatomy and the tear film, keratometry, soft and rigid lens fitting, contact lens optics, care systems and complications.
Work through them in order, or jump straight to whatever you need today.
Read a short lesson on each topic, build recall with spaced-repetition flashcards and keep the formula sheets open while you work.
Answer questions with instant feedback and step-by-step math, then drill the calculations until they are automatic.
Sit a timed mock exam with flags and a navigator, then review every answer and your score by domain.
Timed, flagged and scored by domain
Sit a full mock exam under the clock, then walk back through every answer with the worked math beside it.
Sit a mock examSimulations of the instruments and calculations you use every day in the dispensary, graded by the same engine that marks the exam questions.
Focus the eyepiece, turn the power drum and axis wheel, and read sphere, cylinder, axis and prism from a hidden lens.
Neutralize a lensDial a phoropter with the duochrome and cross-cylinder until the chart is sharp, then over-refract over a contact lens.
Refract a patientFrame calipers for boxing measurements, a Geneva lens clock, and re-marking a progressive lens.
Pick up the calipersRead fluorescein patterns on rigid lenses and take K readings on a keratometer simulator.
Fit a contact lensLens power, prism and vertex distance, with the exam method shown beside exact optics.
Check your workingCall pass or fail on finished spectacle and contact lens orders, then see the tolerance that applies.
Verify a jobEvery ABO optics and NCLE contact lens formula with a worked example. Printable.
View the formulas