Take a Master Exam

[Darryl Meister]

Okay, while we're on the subject of the ABO's Master in Ophthalmic Optics Exam, I have provided a practice test, below. These sample questions are similar to many of the questions from the actual Master Exam I took. (No one really offered practice questions back then though, which made preparation especially difficult.) For those interested in trying some of these questions out, I'll post the answers in a few days so you can see how well you did.

Practice Master Exam

1. Prism-thinning is most often done to reduce thickness in what type of lens?
a. Minus-powered progressive lenses
b. Plus-powered progressive lenses
c. Flat-top bifocal lenses
d. Minus-powered single vision lenses

2. Which spectacle wearer has to accommodate more for a giving working/reading distance?
a. Myope
b. Hyperope
c. Emmetrope
d. They accommodate the same

3. Given a spectacle prescription for a right lens that requires 2D base in, 1.5D at 30, and 0.75D at 60, what would be the resultant prism?
a. 3.93D at 21°
b. 3.93D at 159°
c. 2.75D at 30°
d. 2.75D at 45°

4. If your lens measure reads +6.00 D while measuring the front curve of a 1.66 high-index plastic lens, what is the actual refractive power of the lens surface?
a. +4.82 D
b. +6.00 D
c. +7.47 D
d. +6.25 D

5. What kind of prism can be incorporated into single vision aspheric lenses without significantly affecting lens performance?
a. All prism
b. Prescribed prism
c. Prism for decentration
d. No prism

6. Which spectacle wearer enjoys the widest field of view through his or her lenses?
a. Myope
b. Hyperope
c. Emmetrope
d. They are the same

7. Which organization or agency requires a minimum thickness for dress (non-safety) spectacle lenses?
a. FDA
b. ANSI
c. OSHA
d. None of the above

8. An object 50 cm in front of a +5.00 D lens will come to a focus at what distance from the lens?
a. 25.0 cm in front of the lens
b. 33.3 cm behind the lens
c. 33.3 cm in front of the lens
d. 20.0 cm behind the lens

9. What is the sagitta—or depth—of a 6.00 D curve at 50 mm (assuming a refractive index of 1.530)?
a. 2.8 mm
b. 3.0 mm
c. 3.6 mm
d. 4.5 mm

10. Given a prescription of +10.00 D prescribed at a vertex distance of 13.5 mm, what lens power would be ordered for a vertex distance of 8.5 mm?
a. +10.50 D
b. +9.50 D
c. +10.25 D
d. +9.25 D

11. What type of prescription could be used to make a prosthetic eye appear higher in a depressed socket?
a. Minus cylinder at axis 180
b. Plus cylinder at axis 180
c. Base down prism
d. Base up prism

12. Corrected curve lenses generally reduce what type of lens aberration?
a. Diffraction
b. Spherical aberration
c. Chromatic aberration
d. Oblique astigmatism

13. The reflected images seen from the cornea and crystalline lens are referred to as?
a. Purkinje images
b. After images
c. Aerial images
d. Ghost images

14. The chromatic aberration in the periphery of a spectacle lens is?
a. Directly proportional to the power of the lens
b. Directly proportional to the distance from the optical center
c. Inversely proportional to the Abbe value of the material
d. All of the above

15. Given the following FT-35 bifocal prescription:
+2.00 DS with a +2.50 D add, O.U. (both eyes)
PD’s = 66/62 mm
How could you induce a 1D base in prismatic effect, per eye, at near only?
a. Use a 56 mm distance PD
b. Use a 60 mm near PD
c. Use a 54 mm near PD
d. Can’t be done

16. The transmittance of a Transitions photochromic plastic lens will not depend upon which factor?
a. Lens thickness
b. Temperature
c. Sunlight exposure
d. Age

17. Given the following single vision prescription:
-5.00 DS with 1.5D base in prism, O.U. (both eyes)
PD = 64 mm
Frame eyesize = 54 mm, bridge size= 16 mm, and effective diameter = 64 mm
What would be the minimum blank size required for a finished, stock lens (assuming a 1 mm allowance)?
a. 71 mm
b. 65 mm
c. 68 mm
d. 77 mm

18. A normal eye is most sensitive to which of the following colors during photopic (daylight) vision?
a. Red
b. Blue
c. Green
d. Equally sensitive

19. What is the focal length of a +5.00 D lens?
a. 5.0 m
b. 0.2 cm
c. 25 cm
d. 20 cm

20. If a near PD of 64 is specified for a pair of bifocal lenses with plano distance powers, and the segments are actually fabricated to a near PD of 60, what kind of prism is induced while reading?
a. Base in prism
b. Base out prism
c. Vertical prism
d. No prism

21. What is the ANSI tolerance on the near PD for multifocal segments?
a. 1.5 mm
b. 2.0 mm
c. 2.5 mm
d. 3.0 mm

22. When a lens is tilted, what prescription changes occur?
a. Sphere power is increased; cylinder power equal in sign to sphere power is induced
b. Only cylinder power is induced
c. Sphere power is decreased; cylinder power equal in sign to sphere power is induced
d. Sphere power is increased; cylinder power opposite in sign to sphere power is induced

23. Given an Rx for 4D Base In and 4D Base Up in the right eye (O.D.), what would generally be an acceptable way to split this prism in order to improve cosmetics and comfort?
a. O.D. 4D Base In and 4D Up; O.S. No prism
b. O.D. 2D Base In and 2D Up; O.S. 2D Base Out and 2D Base Down
c. O.D. 2D Base In and 2D Up; O.S. 2D Base In and 2D Base Up
d. O.D. 2D Base In and 2D Up; O.S. 2D Base In and 2D Base Down

24. Which of the following frames will return to its original shape when reheated?
a. Optyl
b. Cellulose Acetate
c. Carbon Fiber
d. Polyamide

25. What is the approximate overall refractive power of a typical human eye?
a. 17 D
b. 43 D
c. 60 D
d. 65 D

26. When the eyes focus on a near object, which of the following processes occur?
a. Eyes converge
b. Lenses accommodate
c. Pupils constrict
d. All of the above

27. Given a distance correction of O.D. +2.00 DS and O.S. +4.00 DS, which eye/lens would have the reverse slab-off applied for a vertical imbalance correction?
a. Right (O.D.) eye/lens
b. Left (O.S.) eye/lens
c. Either lens could use it
d. Neither lens could use it

28. A hard resin lens (CR-39, n = 1.500) loses approximately what percentage of light at each surface due to reflection?
a. 3.5%
b. 4.0%
c. 4.5%
d. 8.0%

29. What is the spherical equivalent of a lens with a power of +1.00 DS -2.00 DC × 180?
a. +1.00 D
b. +0.50 D
c. 0.00 D (plano)
d. -1.00 D

30. A “Hi-Drop” lens would most likely be used for what type of vision condition?
a. Partial sight (low vision)
b. Aphakia
c. Aniseikonia
d. Nystagmus

31. How far should the optical centers of a high-powered lens be placed above or below the pupil for every 2 degrees of pantoscopic tilt?
a. 1 mm above
b. ½ mm below
c. 1 mm below
d. 2 mm below

32. What is the cylinder power of a lens with a front curve of +4.00 D and back curves of -6.50 D and -8.00 D?
a. -1.50 D
b. -4.00 D
c. -2.50 D
d. +2.50 D

33. What is the ANSI Z80.1 tolerance on center thickness when specified?
a. +/-0.25 mm
b. +/-0.30 mm
c. +/-0.50 mm
d. +/-1.00 mm