Block 1 Review TP

Question 1

What’s the optical power of the tear film?

What’s the power of the lens?

What’s the total power of the eye?

Answer 1

48D

20.83

60D

Question 2

What’s the top most layer of tear film?

Answer 2

Oily

Question 3

Tear film stability primarily refers to…?

Answer 3

Evaporation rate

Question 4

Irregularities of the TF over a long period of time improves retinal image quality T/F?

Answer 4

FALSE

Question 5

Dry eye patients generate higher order aberrations like sphere aberration and ___ about 2.5 times more than healthy eyes

Answer 5

Coma

Question 6

Cornea has ____ power of the eye

Lenses have ____

Answer 6

2/3

1/3

Question 7

Anterior corneal asphericity Q value of human cornea is _____

Positive, negative, or zero

Answer 7

Negative

Question 8

What should eve the Q value required to eliminate corneal spherical aberration?

Answer 8

-0.528

Question 9

Spherical aberration will increase as anterior corneal curate ACC becomes…

Bigger, flatter, steeper, thinner??

Answer 9

Steeper

Question 10

If the central corneal thickness CCT gets thicker than normal leads to __________intracellular pressure

Answer 10

Overestimation

Question 11

Which part of the GRIN crystalline lens of the human eye has the lowest refraction index

Equator, nucleus,

Answer 11

POLE

Question 12

Refraction in human eye is due to what three things??

Answer 12

Anterior + posterior + GRIN lens

Question 13

At accommodative state, the refraction of the crystalline lens is….
\

At relaxed state?

Answer 13

32. 85D

21. 25D

Question 14

AA of an eye with far point 1m and near point of 25cm?

Answer 14

3D

Question 15

Crystalline lens axial thickness increases all throughout life at rate of ____________ per year

Answer 15

13 microns

Question 16

In trifocals IOL, potential intermediate vision helps you to ____________ better

Answer 16

Watch TV

Question 17

Extended range of vision IOLs claims to provide good continuous vision and reduce __________

Answer 17

Glare and halo

Question 18

What is the job description of IRIS?

Answer 18

All the above

Question 19

Exit pupil of the aperture stop formed on the image space. T/F?

Answer 19

True

Question 20

Entrance pupil is an erect, _______ image formed in front of actual pupil

Answer 20

Virtual

Question 21

DoF for the human eye is between 0.5D and _____D

Answer 21

1D

Question 22

The line connecting the foveola and the fixation point passing through nodal point

Answer 22

Visual axis

Question 23

The position at which the keratometric axis intercepts the cornea is called ____________

Answer 23

vertex normal

Question 24

Angle between the pupillary axis and Los is?

Answer 24

Angle lambda

Question 25

Disadvantage of using ‘working model’ toy train for solving problems of vision science?

Answer 25

Oversimplified

Question 26

Who was first to develop an average schematic eye?

Answer 26

Listing

Question 27

Applying simplification of the model eye concept, how many surfaces does Bennett rabbetts model have?

Answer 27

3 surfaces

Question 28

Which of the 4 purkinjki images forms images real and inverted?

Purkinji 1,2,3,4??

Answer 28

IV

Question 29

Some corneal topographers and keratometers work based on the principle of______

Answer 29

Purkinji 1

Question 30

Consider light source at infinity and Roc is 7.93mm. Determine the location of Purkinji image by treating anterior corneal surface as a MIRROR

Answer 30

3.965

Take number and divide by 2