ABO NOCE Basic Opticianry Cheat Sheet 2026

The 30 highest-yield ABO NOCE Basic Opticianry facts, distilled from real exam questions. Print it, save it as a PDF, or study it here — free, no sign-up.

1. Which of the following best describes the index of refraction? → The ratio of the speed of light in a vacuum to the speed of light in a medium
2. A patient asks about the difference between standard single vision and aspheric lens designs. The key advantage of aspheric lenses is: → Reduced lens thickness, weight, and peripheral aberrations compared to spherical designs
3. What is the correct minus cylinder transposition of the prescription +1.75 +2.25 x 045? → +4.00 -2.25 x 135
4. Which two types of frame materials are available? → Metal and plastic
5. What is the ANSI Z80.1 tolerance for cylinder axis for a lens with a cylinder power of -1.75 D? → +/- 2 degrees
6. What's the term of the phenomenon where the eye tends to turn from its natural position? → Phoria
7. Which UV light range causes sunburns the most frequently? → 290 nanometers to 320 nanometers
8. The ________ lens at the 90th meridian always reads vertical imbalance error. → weaker
9. When verifying a finished lens with a lensometer, the optical center is found when: → The mire target is centered in the reticle with no prism displacement
10. Which ANSI Z80.1 tolerance applies to the sphere power of a single vision lens with a prescribed power of -4.50 D? → ±0.13 D
11. Which type of lens treatment darkens when exposed to ultraviolet (UV) radiation and returns to clear when indoors? → Photochromic
12. What is the function of a spectacle frame warmer (frame heater)? → To heat plastic frames to make them pliable for adjustment and lens insertion
13. A patient reports that their AR-coated lenses have developed 'crazing' — a network of fine cracks in the coating. What is the most likely cause? → Exposure to heat, such as leaving glasses in a hot car
14. When transposing a prescription from minus to plus cylinder form, the new sphere power will always be: → More minus (or less plus) than the original sphere
15. What is the spherical equivalent of the prescription +2.25 -1.50 x 120? → +1.50 D
16. What is the primary optical advantage of an aspheric lens design compared to a standard spherical design, particularly in higher-powered prescriptions? → It reduces peripheral distortions and improves aesthetics.
17. A patient presents with sudden onset of halos around lights, eye pain, nausea, and blurred vision. This presentation is most consistent with: → Acute angle-closure glaucoma
18. Which type of cataract forms in the central part of the crystalline lens and is associated with excessive UV light exposure and aging? → Nuclear sclerotic cataract
19. What is the Abbe value (V-value) and what does a higher Abbe value indicate? → A measure of chromatic aberration; higher value means less chromatic aberration
20. What is the purpose of an anti-static coating applied to ophthalmic lenses? → To prevent static electricity from attracting dust and particles to the lens surface
21. A lens aberration that causes light of different colors (wavelengths) to focus at different points, resulting in colored fringes around objects, is known as: → Chromatic Aberration
22. What is the correct order in which coatings are typically applied to a standard AR-coated ophthalmic lens? → UV coat → hard coat → AR coat → hydrophobic coat
23. The Americans with Disabilities Act (ADA) requires optical dispensing locations to: → Provide reasonable accommodations and accessible facilities for patients with disabilities
24. In the standard boxing system for frame measurements, what does the 'A' measurement represent? → The horizontal width of the lens box.
25. In a standard gradient tint used in fashion eyewear, how is the tint distributed across the lens? → Darkest at the top, gradually lightening toward the bottom
26. For a lens with a sphere power of +8.00 D, what is the ANSI Z80.1 tolerance for power? → 2% of the power
27. What substance has the best optical qualities? → Crown glass
28. The fovea centralis is important in opticianry because: → It provides the highest visual acuity and is the target for optical center placement
29. A lens's power is indicated by the word "axis." → False
30. A plus power lens is essentially two prisms oriented in which configuration? → Base to base