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Home
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ABO Review
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ABO Review Quiz 3 – Lens Form
ABO Review Quiz 3 – Lens Form
ABO Review Quiz - Lens Form
OpenOptix ABO Study Guide
: Chapter 3
31 Questions
A lens clock is used to measure
astigmatism
pupillary distance
vertex distance
base curve
Transpose the following prescription: +2.25 +1.75 X 085
+2.25 -1.75 X 085
-4.00 +1.75 X 175
+4.00 -1.75 X 175
-2.25 +1.75 X 085
Equiconcave, flat concave, and meniscus are ALL types of
minus lenses
plus lenses
astigmatic lenses
spherocylinder lenses
Equiconvex, flat convex, and meniscus are ALL types of:
minus lenses
plus lenses
astigmatic lenses
spherocylinder lenses
The reason for using a "best form" lens is to minimize
aberrations
weight
magnification
index
A lens has a front surface power of +2.00D and a back surface power of -8.25D. The corrective power is
-8.25D
-5.75D
+2.00D
-6.25D
What is the best base curve for a -3.75D lens?
4
2
-4
-2
Using the prescription +2.00 -1.50 X 45, what is the power of the lens at the 90th meridian?
0.5
2
1.25
-0.5
How much cylinder power is in effect at the specified axis?
0%
25%
50%
100%
A plus lens
diverges light
converges light
is two prisms placed apex to apex
is concave
A minus lens
is thick in the center
converges light
is thin in the center
is two prisms placed base to base
Transpose the following prescription: -0.75 +3.00 X 180
+2.25 -3.00 X 180
-0.75 -3.00 X 090
+2.25 +3.00 X 180
+2.25 -3.00 X 090
Using the prescription -1.00 -1.50 X 90, what is the power of the lens at the 180th meridian?
-2.5
-1
-0.5
-1.5
What is the best base curve for a +2.50D lens?
8
6
10
4
Eyeglass prescription powers are written in _________.
Axis
Prisms
diopters
degrees
Axis is ____________.
a notation of position
a notation of power on a lens
always greater than 180 degrees
used on spherical Rx
To switch between minus and plus cylinder forms we use _____.
cylinder conversion
the cylinder powers formula
transposition
degree conversion
Plus lenses ________ and minus lenses ________.
magnify, minify
Minify, magnify
Neutralize, verify
Myopia, hyperopia
The spherical equivalent of the lens +1.00 +2.50 x 90 is:
+1.50D
+2.25D
+2.50D
+3.50D
If the prescription is O.D. +1.00 +2.50 x 45, what would be the total power at axis 90?
+1.00D
+2.00D
+2.25D
+2.SOD
Which of the following lenses has no power in the 90
+2.00 -2.00 x 90
+2.00 +2.00 x 180
+1.00-2.00 x 45
+1.00+1.00x135
Given an Rx with all specifications equal but ground in material of different indices, which set of lenses will be the thinnest?
Crown glass
Polycarbonate
CR-39
Photo-Gray Extra
A lens having one concave and one convex surface is called a __________ lens.
Biconvex
Toric
Biconcave
Meniscus
The dioptric difference between the lenses for the prescription of O.D. +2.00 sph, O.S. +0.50 sph would be:
0.50D
l.00D
1.50D
2.00D
Astigmatism is corrected by a lens having:
Plus power
Minus power
Cylinder power
Prism Power
Given the prescription +1.00 +1.00 axis 90, how much of the +1.00 cylinder is in effect at axis 90 (the vertical meridian of the lens)?
100%
90%
50%
0%
A myope always has in his or her prescription the following kind of power:
Minus power
Plus power
Cylinder power
Axis
A hyperope always has in his or her prescription the following power:
Minus power
Plus power
Cylinder power
axis
If a +10D lens is moved 5 mm nearer the eye, it will be about:
0.25D stronger plus
0.25D weaker plus
0.50D stronger plus
0.50D weaker plus
The relationship of front and back curvatures on a spectacle lens will determine:
Refractive power
Segment position
Effective diameter
Decentration
How much cylinder power is in effect 90 degrees away from the specified axis?
0%
50%
25%
100%
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