ABO ADVANCED CERTIFICATION SCRIPT Questions with
Correct Answers (Grade A+)
Question 1: Resolving Prism=.
Answer: Vertical = (prism)(sin angle) Horizontal = (prism) (cos angle)
Question 2: Base Curve.
Answer: Curvature of the front of the lens
Question 3: Resultant Prism=.
Answer: The square root of (Vertical prism^2) + (Horizontal prism^2)tan a=V/H
Question 4: How is Cyl ground on a minus cyl lens?
Answer: Single curve on the front. Cyl ground on the back
Question 5: Shape Factor=.
Answer: 1/1-(T/NxF)T=center thickness in mN= index of refraction of lens materialF= front base curve
Question 6: Power Factor=.
Answer: 1/1-(HxD)H= vertex distance plus 3 mm in mD= Dioptric power
Question 7: How is cyl ground on a plus cyl lens?
Answer: Flattest curve on the front. Old way of doing it do to cosmetics
Question 8: What is Vogels formula used for?
Answer: Creating best form and n standard surfacing
Question 9: Spectacle Magnification=.
Answer: shape factor x power factor 1/ 1-(T/NxF) x 1/1-(HxD)
Question 10: Power in Oblique Meridians=.
Answer: Total power = sphere power + cyl power x sin^2 (O)
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,Question 11: Snell's Law=.
Answer: N1 sin i = N2 sin rN1= index of refraction of incident medium i= angle of incidenceN2= index of
refraction of refracting mediumr= angle of refraction
Question 12: Angle of reflection=.
Answer: angle I= angle rI= angle of incidencer= angle of reflection
Question 13: Vogel's Formula (+ lenses).
Answer: Spherical equivalent + 6.00
Question 14: Angle of incidence=.
Answer: I=r+dI= angle of incidencer= angle of refractiond= deviation
Question 15: Index of refraction=.
Answer: Speed of light in a vacuum/Speed of light in the medium
Question 16: Vogel's Formula (- lenses).
Answer: Spherical equivalent + 6.
Question 17: Corrected Curve Theory rules:.
Answer: #1 ocular curves (minus side) that fall between -4.00 - -7.00 are best for delivering non abbe rated
vision#2 -as minus increases BC should flatten- as plus increases BC should steepen
Question 18: What are the 2 base curves every lens has?
Answer: Nominal - general category (ex. 4.25 or 6.00)Actual/True curve- real measured curve/sag depth
Question 19: Prentice Rule=.
Answer: Prism= (hxd)/10h=distance moved in mmD= total dioptric power for the meridian
Question 20: Thick Lens Back Vertex Power=.
Answer: De= D1+D2+ (t/n x D1^2)De= effective, vertex or lensometer powerD1= true power of the front
curveD2= ture power of the back curvet= lens thickness in metersn= index of refraction
Question 21: Index of refracting formula.
Answer: Speed of light in air/speed of light in material
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, Question 22: Speed of light in air?
Answer: 186,000 miles per second
Question 23: Flint glass index of refraction and abbe value.
Answer: 1.58-1.69 & 30-40
Question 24: Focal length.
Answer: D=1/fD= dioptric powerf= focal length in meters
Question 25: Barium glass index of refraction and abbe value.
Answer: 1.51-1.616 & 55-59
Question 26: Highlite glass index of refraction and abbe value.
Answer: 1.70 & 32
Question 27: Dioptric formula.
Answer: f=1/DD= dioptric powerf= focal length in meters
Question 28: CR39 index of refraction and abbe value.
Answer: 1.49 & 58
Question 29: Vertex power compensation (if the wearing vertex is less than the refractive vertex)=.
Answer: Fb= (Fa)/ 1-(dFa)Fa= primary focal length of the refractive vertexFb= Compensated powerd=
distance in meters that the lens is moved from the refractive vertex to the wearing vertex
Question 30: Vertex power compensation (if the wearing vertex is more than the refractive vertex)=.
Answer: Fb= (Fa)/ 1+(dFa)Fa= primary focal length of the refractive vertexFb= Compensated powerd=
distance in meters that the lens is moved from the refractive vertex to the wearing vertex
Question 31: What is the vertex power compensation for a low powered lens?
Answer: Per mm= (D^2)/1000D= dioptric power
Question 32: Dioptric power=.
Answer: D= (n-1)/rr= radius in metersD= Dioptric power of a curven= index of refraction
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Correct Answers (Grade A+)
Question 1: Resolving Prism=.
Answer: Vertical = (prism)(sin angle) Horizontal = (prism) (cos angle)
Question 2: Base Curve.
Answer: Curvature of the front of the lens
Question 3: Resultant Prism=.
Answer: The square root of (Vertical prism^2) + (Horizontal prism^2)tan a=V/H
Question 4: How is Cyl ground on a minus cyl lens?
Answer: Single curve on the front. Cyl ground on the back
Question 5: Shape Factor=.
Answer: 1/1-(T/NxF)T=center thickness in mN= index of refraction of lens materialF= front base curve
Question 6: Power Factor=.
Answer: 1/1-(HxD)H= vertex distance plus 3 mm in mD= Dioptric power
Question 7: How is cyl ground on a plus cyl lens?
Answer: Flattest curve on the front. Old way of doing it do to cosmetics
Question 8: What is Vogels formula used for?
Answer: Creating best form and n standard surfacing
Question 9: Spectacle Magnification=.
Answer: shape factor x power factor 1/ 1-(T/NxF) x 1/1-(HxD)
Question 10: Power in Oblique Meridians=.
Answer: Total power = sphere power + cyl power x sin^2 (O)
Page 1
,Question 11: Snell's Law=.
Answer: N1 sin i = N2 sin rN1= index of refraction of incident medium i= angle of incidenceN2= index of
refraction of refracting mediumr= angle of refraction
Question 12: Angle of reflection=.
Answer: angle I= angle rI= angle of incidencer= angle of reflection
Question 13: Vogel's Formula (+ lenses).
Answer: Spherical equivalent + 6.00
Question 14: Angle of incidence=.
Answer: I=r+dI= angle of incidencer= angle of refractiond= deviation
Question 15: Index of refraction=.
Answer: Speed of light in a vacuum/Speed of light in the medium
Question 16: Vogel's Formula (- lenses).
Answer: Spherical equivalent + 6.
Question 17: Corrected Curve Theory rules:.
Answer: #1 ocular curves (minus side) that fall between -4.00 - -7.00 are best for delivering non abbe rated
vision#2 -as minus increases BC should flatten- as plus increases BC should steepen
Question 18: What are the 2 base curves every lens has?
Answer: Nominal - general category (ex. 4.25 or 6.00)Actual/True curve- real measured curve/sag depth
Question 19: Prentice Rule=.
Answer: Prism= (hxd)/10h=distance moved in mmD= total dioptric power for the meridian
Question 20: Thick Lens Back Vertex Power=.
Answer: De= D1+D2+ (t/n x D1^2)De= effective, vertex or lensometer powerD1= true power of the front
curveD2= ture power of the back curvet= lens thickness in metersn= index of refraction
Question 21: Index of refracting formula.
Answer: Speed of light in air/speed of light in material
Page 2
, Question 22: Speed of light in air?
Answer: 186,000 miles per second
Question 23: Flint glass index of refraction and abbe value.
Answer: 1.58-1.69 & 30-40
Question 24: Focal length.
Answer: D=1/fD= dioptric powerf= focal length in meters
Question 25: Barium glass index of refraction and abbe value.
Answer: 1.51-1.616 & 55-59
Question 26: Highlite glass index of refraction and abbe value.
Answer: 1.70 & 32
Question 27: Dioptric formula.
Answer: f=1/DD= dioptric powerf= focal length in meters
Question 28: CR39 index of refraction and abbe value.
Answer: 1.49 & 58
Question 29: Vertex power compensation (if the wearing vertex is less than the refractive vertex)=.
Answer: Fb= (Fa)/ 1-(dFa)Fa= primary focal length of the refractive vertexFb= Compensated powerd=
distance in meters that the lens is moved from the refractive vertex to the wearing vertex
Question 30: Vertex power compensation (if the wearing vertex is more than the refractive vertex)=.
Answer: Fb= (Fa)/ 1+(dFa)Fa= primary focal length of the refractive vertexFb= Compensated powerd=
distance in meters that the lens is moved from the refractive vertex to the wearing vertex
Question 31: What is the vertex power compensation for a low powered lens?
Answer: Per mm= (D^2)/1000D= dioptric power
Question 32: Dioptric power=.
Answer: D= (n-1)/rr= radius in metersD= Dioptric power of a curven= index of refraction
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