ABO, ABO STUDY GUIDE QUESTIONS
ACCURATELY SOLVED
Prentice Rule - CORRECT ANSWER✅✅✅(Power x distance in mm) /10
Cornea index of refraction - CORRECT ANSWER✅✅✅1.37
Tear Film, Vitreous index of refraction - CORRECT ANSWER✅✅✅1.33
Crystalline lens index of refraction - CORRECT ANSWER✅✅✅1.42
Optical Standard index of refraction - CORRECT ANSWER✅✅✅1.53
Crown Glass index of refraction - CORRECT ANSWER✅✅✅1.523
High index of refraction - CORRECT ANSWER✅✅✅1.74
CR-39 index of refraction - CORRECT ANSWER✅✅✅1.49/1.50
Poly index of refraction - CORRECT ANSWER✅✅✅1.586
Air - CORRECT ANSWER✅✅✅1.00
How fast does light travel through air - CORRECT ANSWER✅✅✅186,000 mi/sec
MBS formula - CORRECT ANSWER✅✅✅ED+2 (decentration)+2
,Focal length formula - CORRECT ANSWER✅✅✅1/Dioptic Power power
Dioptic Power formula - CORRECT ANSWER✅✅✅1/Focal Length
Antimetropia - CORRECT ANSWER✅✅✅Rx with unlike signs in both eyes
Anisometropia - CORRECT ANSWER✅✅✅Difference of 2 diopters btwn OD & OS
Anisiekonia - CORRECT ANSWER✅✅✅When images from right and left eye are so
different the brain can not achieve fusion
What is the Radius of a 1 diopter curve? - CORRECT ANSWER✅✅✅530mm
Radius formula - CORRECT ANSWER✅✅✅530/Power = Radius
Power formula - CORRECT ANSWER✅✅✅530/Radius = Power
Vertical Decentration formula - CORRECT ANSWER✅✅✅Seg.ht. - B/2
How much HORIZONTAL prism tolerance is allowed? - CORRECT ANSWER✅✅✅2/3 of
a diopter
-or-
0.667
How much VERTICAL prism tolerance is allowed? - CORRECT ANSWER✅✅✅1/3 of a
diopter
-or-
0.333
, Base Curve tolerance - CORRECT ANSWER✅✅✅+/-0.75
Sphere Tolerance up to 6.50 - CORRECT ANSWER✅✅✅+/- 0.13
Sphere Tolerance above 6.50 - CORRECT ANSWER✅✅✅+/- 2%
Cylinder Tolerance >1.50 - CORRECT ANSWER✅✅✅+/-2°
Cylinder Tolerance >0.50 / less than or equal to 1.50 - CORRECT ANSWER✅✅✅+/-3°
Cylinder Tolerance >0.25 / less than or equal to 0.50 - CORRECT ANSWER✅✅✅+/-7°
Cylinder Tolerance >0.00 / less than or equal to 0.25 - CORRECT ANSWER✅✅✅+/-14°
Drop ball test for Safety lenses - CORRECT ANSWER✅✅✅5/8ths in diameter, weighing
0.56oz dropped 50ft
Frame PD - CORRECT ANSWER✅✅✅A box + DBL
Total decentration - CORRECT ANSWER✅✅✅Frame PD - Patient PD
Base IN (MINUS) - CORRECT ANSWER✅✅✅If frame PD is GREATER than customer
PD
Base OUT (MINUS) - CORRECT ANSWER✅✅✅If frame PD is LESS than customer PD
Which layer of the cornea is highly regenerative? - CORRECT ANSWER✅✅✅Epithelium
ACCURATELY SOLVED
Prentice Rule - CORRECT ANSWER✅✅✅(Power x distance in mm) /10
Cornea index of refraction - CORRECT ANSWER✅✅✅1.37
Tear Film, Vitreous index of refraction - CORRECT ANSWER✅✅✅1.33
Crystalline lens index of refraction - CORRECT ANSWER✅✅✅1.42
Optical Standard index of refraction - CORRECT ANSWER✅✅✅1.53
Crown Glass index of refraction - CORRECT ANSWER✅✅✅1.523
High index of refraction - CORRECT ANSWER✅✅✅1.74
CR-39 index of refraction - CORRECT ANSWER✅✅✅1.49/1.50
Poly index of refraction - CORRECT ANSWER✅✅✅1.586
Air - CORRECT ANSWER✅✅✅1.00
How fast does light travel through air - CORRECT ANSWER✅✅✅186,000 mi/sec
MBS formula - CORRECT ANSWER✅✅✅ED+2 (decentration)+2
,Focal length formula - CORRECT ANSWER✅✅✅1/Dioptic Power power
Dioptic Power formula - CORRECT ANSWER✅✅✅1/Focal Length
Antimetropia - CORRECT ANSWER✅✅✅Rx with unlike signs in both eyes
Anisometropia - CORRECT ANSWER✅✅✅Difference of 2 diopters btwn OD & OS
Anisiekonia - CORRECT ANSWER✅✅✅When images from right and left eye are so
different the brain can not achieve fusion
What is the Radius of a 1 diopter curve? - CORRECT ANSWER✅✅✅530mm
Radius formula - CORRECT ANSWER✅✅✅530/Power = Radius
Power formula - CORRECT ANSWER✅✅✅530/Radius = Power
Vertical Decentration formula - CORRECT ANSWER✅✅✅Seg.ht. - B/2
How much HORIZONTAL prism tolerance is allowed? - CORRECT ANSWER✅✅✅2/3 of
a diopter
-or-
0.667
How much VERTICAL prism tolerance is allowed? - CORRECT ANSWER✅✅✅1/3 of a
diopter
-or-
0.333
, Base Curve tolerance - CORRECT ANSWER✅✅✅+/-0.75
Sphere Tolerance up to 6.50 - CORRECT ANSWER✅✅✅+/- 0.13
Sphere Tolerance above 6.50 - CORRECT ANSWER✅✅✅+/- 2%
Cylinder Tolerance >1.50 - CORRECT ANSWER✅✅✅+/-2°
Cylinder Tolerance >0.50 / less than or equal to 1.50 - CORRECT ANSWER✅✅✅+/-3°
Cylinder Tolerance >0.25 / less than or equal to 0.50 - CORRECT ANSWER✅✅✅+/-7°
Cylinder Tolerance >0.00 / less than or equal to 0.25 - CORRECT ANSWER✅✅✅+/-14°
Drop ball test for Safety lenses - CORRECT ANSWER✅✅✅5/8ths in diameter, weighing
0.56oz dropped 50ft
Frame PD - CORRECT ANSWER✅✅✅A box + DBL
Total decentration - CORRECT ANSWER✅✅✅Frame PD - Patient PD
Base IN (MINUS) - CORRECT ANSWER✅✅✅If frame PD is GREATER than customer
PD
Base OUT (MINUS) - CORRECT ANSWER✅✅✅If frame PD is LESS than customer PD
Which layer of the cornea is highly regenerative? - CORRECT ANSWER✅✅✅Epithelium
