Optometry final exam UPDATED ACTUAL Questions and CORRECT Answers
1. emmetropia optical state of the eye in which parallel light enters the eye and focuses on
the retina without the need for any corrective lenses or accommodation;
this is the absence of refractive error and the "normal" or ideal state of the
eye
2. ametropia refractive error, "abnormal" optical state of the eye in which parallel light
rays enter the eye and focus on an area other than the retina; this condition
requires corrective lenses to produce clear retinal images
3. astigmatism optical error in which refractive power is not uniform in all meridians; light
entering the eye is focused at two distinct focal points where at least one
focal point does not fall onto the retina
4. How can corneal astig- keratometry
matism be measured?
5. What are compo- 1. Power (magnitude in D) of sphere component
nents of sphere-cylin- 2. Power (magnitude of D) of cylinder component
der lens RX? 3. Axis (orientation) of the cylinder
i.e. +2.00 -3.00 X 145
i.e. -5.00 -2.00 X 060
6. If one meridian is at 60 150 degrees because 60+90=150
degrees, where is the
other
7. What are the possible 1 degree-180 degrees
values for magnitude
of axis?
8. How can one deter- Principal meridian 1=power of more (+) meridian
mine the powers of Principal meridian 2=sum of sphere and cylinder componenets
, the 2 principal meridi-
ans?
9. Find primary and sec- Principal meridian 1=+1.00D
ondary meridians for Principal meridian 2=+1.00D + -2.00D= -1.00D
this Rx.
+1.00 -2.00 X 110
10. Find the primary and Principal meridian 1= -3.00D
secondary meridians Principal meridian 2= -3.00D + -4.50D= -7.50D
for the Rx.
-3.00 -4.50 X 010
11. Find the primary and Principal meridian 1= +4.00D
secondary meridians Principal meridian 2= +4.00D - 6.50D= -2.50D
for this Rx.
+4.00 -6.50 X 175
12. What are the 8 differ- 7 distance refractive errors which assume that accommodation is at rest
ent types of refractive and that the eye is looking at a distant target (optical infinity)
error? 1 near refractive error that involves a target closer than optical infinity and
may involve accommodation
13. Define diopter unit of measurement of the refractive power of the lens, and is equal to
the reciprocal of the focal length as measured in meters
14. What is the focal point 0.5 m or 50 cm
of a +2.00D lens?
15. What is the dioptric +5.00 D
power of a lens that
has a focal point of 20
cm?
, 16. Define spherical re- Refractive error is uniform in all meridians. No matter where cross-section
fractive error is taken, the refractive error is the same magnitude throughout
17. Define hyperopia parallel light entering the eye is focused behind the retina and requires a
plus lens to converge the light to properly focus it on the retina; eye has
too much minus power
18. Define myopia parallel light entering the eye is focused in front of the retina and requires
a minus lens to diverg the light to properly focus it on the retina; eye has
too much plus power
19. What kind of lens is the two focal lengths need a lens with 2 different powers to bring the
necessary to correct light to one single focal point on the retina; a sphere-o-cylinder lens
for astigmatism? (compound lens or sphere-cylinder lens) has one power in one meridian
and a different power in the other meridian located 90 degrees away
20. Define principal two primary refractive cross sections of astigmatic refractive error; each
meridians principal meridian has a power and orientation from 1-180 degrees and
are located 90 degrees away from each other
21. How can one describe magnitude in diopters and orientations as measured by axis
amount of astigma-
tism?
22. What does prescription with an axis closer to 180 degrees
with-the-rule astigma-
tism refer to?
23. What does prescription with an axis closer to 90 degrees
against-the-rule astig-
matism refer to?
24. What does oblique prescription that has an axis closer to 45 degrees or 135 degrees
astigmatism refer to?
1. emmetropia optical state of the eye in which parallel light enters the eye and focuses on
the retina without the need for any corrective lenses or accommodation;
this is the absence of refractive error and the "normal" or ideal state of the
eye
2. ametropia refractive error, "abnormal" optical state of the eye in which parallel light
rays enter the eye and focus on an area other than the retina; this condition
requires corrective lenses to produce clear retinal images
3. astigmatism optical error in which refractive power is not uniform in all meridians; light
entering the eye is focused at two distinct focal points where at least one
focal point does not fall onto the retina
4. How can corneal astig- keratometry
matism be measured?
5. What are compo- 1. Power (magnitude in D) of sphere component
nents of sphere-cylin- 2. Power (magnitude of D) of cylinder component
der lens RX? 3. Axis (orientation) of the cylinder
i.e. +2.00 -3.00 X 145
i.e. -5.00 -2.00 X 060
6. If one meridian is at 60 150 degrees because 60+90=150
degrees, where is the
other
7. What are the possible 1 degree-180 degrees
values for magnitude
of axis?
8. How can one deter- Principal meridian 1=power of more (+) meridian
mine the powers of Principal meridian 2=sum of sphere and cylinder componenets
, the 2 principal meridi-
ans?
9. Find primary and sec- Principal meridian 1=+1.00D
ondary meridians for Principal meridian 2=+1.00D + -2.00D= -1.00D
this Rx.
+1.00 -2.00 X 110
10. Find the primary and Principal meridian 1= -3.00D
secondary meridians Principal meridian 2= -3.00D + -4.50D= -7.50D
for the Rx.
-3.00 -4.50 X 010
11. Find the primary and Principal meridian 1= +4.00D
secondary meridians Principal meridian 2= +4.00D - 6.50D= -2.50D
for this Rx.
+4.00 -6.50 X 175
12. What are the 8 differ- 7 distance refractive errors which assume that accommodation is at rest
ent types of refractive and that the eye is looking at a distant target (optical infinity)
error? 1 near refractive error that involves a target closer than optical infinity and
may involve accommodation
13. Define diopter unit of measurement of the refractive power of the lens, and is equal to
the reciprocal of the focal length as measured in meters
14. What is the focal point 0.5 m or 50 cm
of a +2.00D lens?
15. What is the dioptric +5.00 D
power of a lens that
has a focal point of 20
cm?
, 16. Define spherical re- Refractive error is uniform in all meridians. No matter where cross-section
fractive error is taken, the refractive error is the same magnitude throughout
17. Define hyperopia parallel light entering the eye is focused behind the retina and requires a
plus lens to converge the light to properly focus it on the retina; eye has
too much minus power
18. Define myopia parallel light entering the eye is focused in front of the retina and requires
a minus lens to diverg the light to properly focus it on the retina; eye has
too much plus power
19. What kind of lens is the two focal lengths need a lens with 2 different powers to bring the
necessary to correct light to one single focal point on the retina; a sphere-o-cylinder lens
for astigmatism? (compound lens or sphere-cylinder lens) has one power in one meridian
and a different power in the other meridian located 90 degrees away
20. Define principal two primary refractive cross sections of astigmatic refractive error; each
meridians principal meridian has a power and orientation from 1-180 degrees and
are located 90 degrees away from each other
21. How can one describe magnitude in diopters and orientations as measured by axis
amount of astigma-
tism?
22. What does prescription with an axis closer to 180 degrees
with-the-rule astigma-
tism refer to?
23. What does prescription with an axis closer to 90 degrees
against-the-rule astig-
matism refer to?
24. What does oblique prescription that has an axis closer to 45 degrees or 135 degrees
astigmatism refer to?
