Final

Question 1

What’s another word for purkinje image?

Answer 1

catoptric

Question 2

Which purkinje image is the only one where you see against motion?

Answer 2

IV

Question 3

Purkinje images I - IV are ___ order and are formed by reflection at ____ surface. Purkinje images V - VI are ____ order and are formed by reflection at ___ surfaces.

Answer 3

Purkinje images I - IV are first order and are formed by reflection at one surface. Purkinje images V - VI are second order and are formed by reflection at two surfaces.

Question 4

Which purkinje image is found in the vitreous?

Answer 4

III

Question 5

Relative sizes of purkinje images in unaccommodated eye?

Answer 5

III > I > II > IV

Question 6

Relative sizes of purkinje images in accommodated eye?

Answer 6

I > II > III > IV

Question 7

How many refracting surfaces are there in the Gullstrand exact eye model? Simplified Schematic? Reduced eye?

Answer 7

6
3
1

Question 8

In the cornea, the anterior surface has a ____ radius of curvature compared to the posterior surface

Answer 8

smaller

Question 9

When are the nodal points coincident with H and H prime?

Answer 9

when n1 = n3

Question 10

How do you measure axial length?

Answer 10

ultrasound

IOL master

Question 11

How do you measure the anterior chamber depth?

Answer 11

Usually ultrasound

slit lamp

Question 12

How do you measure corneal thickness?

Answer 12

ultrasound

Question 13

How do you measure lens thickness?

Answer 13

ultrasound

Question 14

What is Pachymetry?

Answer 14

Measuring corneal thickness

Question 15

What is Phakometry?

Answer 15

Measure lens curvature

Question 16

What is the angle between the optic and visual axes, formed at nodal point?

Answer 16

Angle Alpha

Question 17

What is the angle between pupillary axis and line of sight, formed at entrance pupil?

Answer 17

Angle Lambda

Question 18

What is the angle between pupillary axis and visual axis, although entrance pupil and nodal point need not fall on the same line?

Answer 18

Angle Kappa

Question 19

What is the angle between optic and fixation axes, formed at center of rotation of globe?

Answer 19

Angle Gamma

Question 20

The optical axis connects the ____ of _____ of various optical elements of the eye; this line should go through the ____ points and is _____ to all the refracting surfaces

Answer 20

The optical axis connects the centers of curvature of various optical elements of the eye; this line should go through the nodal points and is perpendicular to all the refracting surfaces

Question 21

The visual axis is a line connecting the _____ point, nodal points, and the _____

Answer 21

The visual axis is a line connecting the fixation point, nodal points, and the fovea

Question 22

The pupillary axis is a line normal to the cornea that passes through the center of the ___ ___

Answer 22

entrance pupil

Question 23

The line of sight is a line connecting the ______ point and the entrance pupil

Answer 23

fixation point

Question 24

The fixation axis is a line connecting the fixation point to the ____ of ____ of the globe

Answer 24

center of rotation

Question 25

What are the different types of ultrasound imaging?

Answer 25

A scan - amplitude modification B scan - time-brightness method M scan - movement mode

Question 26

When the eye s too long for its refractive power, the result is _____

Answer 26

myopia

Question 27

When the eye is too short for its refractive power, the result is _____

Answer 27

hyperopia

Question 28

An increase in curvature of what surfaces results in greater positive refractive power and a shift towards myopia?

Answer 28

Anterior cornea Anterior lens Posterior lens

Question 29

And increase in curvature of the ______ _____ results in less refractive power of the cornea, resulting in a shift towards hyperopia

Answer 29

Posterior cornea

Question 30

What does shifting the lens forward toward the cornea do?

Answer 30

Increase refractive power of the eye

Question 31

What does shifting the crystalline lens backward away from the cornea do?

Answer 31

Decreases refractive power of the eye

Question 32

And increase in refractive index causes what optical elements to increase in refractive power and result in a shift towards myopia?

Answer 32

Aqueous humor | crystalline lens nucleus

Question 33

An increase in refractive index causes what optical elements to decrease in refractive power and results in a shift towards hyperopia?

Answer 33

Cornea Crystalline lens cortex Vitreous humor

Question 34

What is the difference between spectacle magnification and relative spectacle magnification?

Answer 34

SM - Retinal image size of the corrected vs uncorrected ametropic eye RSM - Retinal image size of the corrected ametropic eye vs the emmetropic eye

Question 35

What is Knapp's Rule?

Answer 35

Correct axial anisometropia with spectacle | Correct refractive anisometropia with contacts

Question 36

When does RSM = SM?

Answer 36

Refractive ametropia

Question 37

What is the difference between a Galilean telescope and an Astronomical telescope?

Answer 37

Galilean - Positive objective and negative eyepiece | Astronomical - Positive objective and positive eyepiece

Question 38

The entrance port is the image of the field stop formed by the lenses _____ it.

Answer 38

in front of it. | If there are none, then field stop = entrance port

Question 39

The exit port is the image of the field stop formed by the lenses ____ it.

Answer 39

behind it. | If there are none, field stop = exit port

Question 40

The angle subtended by the entrance port at the enter of the entrance pupil is the ____ field of view

Answer 40

object field of view

Question 41

The angle subtended by the exit port at the center of the exit pupil is the ____ field of view

Answer 41

Image field of view | Also "apparent" field of view

Question 42

If unqualified, field of view means ____ field of view

Answer 42

object field of view

Question 43

A ______ ___ is a ray that leave an off-axis object point and heads toward the edge of the entrance pupil

Answer 43

marginal ray

Question 44

What happens when a chief ray from an off-axis point gets through the system but the marginal rays do not?

Answer 44

vignetting