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's prescription reads OD -3.50 -1.25 x 090. The principal meridians of power are: → -3.50 D at 090 and -4.75 D at 180
3. Which of the following frame materials should NEVER be placed in a salt pan or frame warmer? → Optyl
4. The distometer is used in opticianry to measure which parameter? → The vertex distance between the back of the lens and the cornea
5. 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
6. A pupillometer differs from a PD ruler in that it: → Uses a light reflection from the cornea for more accurate monocular PD measurement
7. What is the correct minus cylinder transposition of the prescription +1.75 +2.25 x 045? → +4.00 -2.25 x 135
8. A patient complains of swimming or swaying when wearing new progressives. Which verification step should the optician prioritize? → Measuring the monocular PD at the fitting cross
9. Which two types of frame materials are available? → Metal and plastic
10. What is the purpose of the ink dots placed on a lens after neutralization with a lensometer? → To mark the optical center and axis
11. Which instrument is used to measure the base curve of a finished lens? → Geneva lens clock
12. The term 'face form' or 'wrap angle' refers to: → The curvature of the frame front as it wraps around the face horizontally
13. What is the ANSI Z80.1 tolerance for cylinder axis for a lens with a cylinder power of -1.75 D? → +/- 2 degrees
14. A frame has a 'B' measurement of 38 mm and a DBL of 18 mm. What is the frame's 'A' measurement needed to calculate minimum blank size? → It cannot be determined from B and DBL alone
15. A patient reports that their new glasses feel 'swimmy' (objects appear to move). This is most commonly caused by: → A significant change in prescription or incorrect pantoscopic tilt with progressive lenses
16. The critical angle for total internal reflection depends on: → The refractive indices of both media at the interface
17. What's the term of the phenomenon where the eye tends to turn from its natural position? → Phoria
18. What is the primary purpose of the distance between lenses (DBL) measurement? → To determine the width of the bridge
19. The minimum fitting height for a lined bifocal segment is typically measured from: → The lower lid margin to the bottom of the frame
20. ANSI Z80.1 requires that the segment height of a lined bifocal be within what vertical tolerance of the specified height? → ±1.0 mm
21. Which UV light range causes sunburns the most frequently? → 290 nanometers to 320 nanometers
22. The pars plana is a clinically important structure because it is the preferred site for: → Intravitreal injections and vitrectomy incisions
23. Which type of collagen is the primary structural component of the corneal stroma? → Type I collagen
24. Which instrument is used to measure the vertex distance between the back surface of a spectacle lens and the front of the cornea? → Distometer (vertex distance gauge)
25. What does the term 'specific gravity' refer to when describing lens materials? → The density of a material relative to water
26. A HIPAA Business Associate Agreement (BAA) is required when an optical practice shares PHI with: → A third-party lab that receives patient prescriptions to fabricate lenses
27. Per ANSI Z80.1, what is the maximum allowable induced prism at the MRP for a single-vision lens with power greater than ±3.375 D? → 0.67Δ
28. The crystalline lens derives its nutrition primarily from which source? → Aqueous humor
29. A patient's prescription reads +2.50 -1.25 x 090. What is the sphere power of the lens? → +2.50 D
30. A screwdriver used in optical frame repair should have which tip to avoid stripping tiny eyeglass screws? → A precision flat-blade or JIS tip sized specifically for optical screws