3-4 Monochromatic Aberrations

Question 1

Defocus, astigmatism, coma, trefoil, and spherical aberrations are examples of what?

Answer 1

Monochromatic aberrations

Question 2

Longitudinal and transverse aberrations are of what category?

Answer 2

Chromatic Aberrations

Question 3

The significance of chromatic defocus depends on _______

Answer 3

Luminance

Question 4

When the peak of luminance spectru, is in focus, most of the light is less than ___D out of focus.

So when images are superimposed on retina, visibility of target dominated by _______ that are slightly defocused

Answer 4

0.25D

Wavelengths

Question 5

How many diopters for Longitudinal (LCA)??

Answer 5

2.1D

Question 6

What’s the average D value for transverse (TCA)?

Is this same if each person measured individually?

Answer 6

0

NO! Will vary greatly but all of them average to 0

Question 7

Lower wavelength makes the eye more _____. Higher wavelength makes the eye more_____

Answer 7

Myopic

Hyperopic

Question 8

The chromatic difference of focus (CDF) reduces retinal image contrast by __D of defocus

Answer 8

0.2D

Question 9

Magnification (CDM) is equal to the axial distance (z) from _____ to ____ point

Answer 9

Pupil; nodal point

Question 10

Can a CDM less than 1% produce dramatic effects on depth perception?

Answer 10

YES

Question 11

The chromatic difference of position is directly proportional to :

_____________ (peripheral vision)

__________ (foveal vision)

Answer 11

Stimulus eccentricity

Lateral displacement

Question 12

A decentered pupil causes tons of ____ when using pinhole

Answer 12

TCA

Transverse chromatic aberration

Question 13

If you shift your pupil 1mm…you are displaced by ____ degrees or ___ degrees of eccentricity.

Do they both generate the same amount of TCA?

Answer 13

0.12 deg

15 degrees!

Yessssiiirrrr

Question 14

Transverse chromatic aberration increases _______ with eccentricity

Answer 14

Linearly

Question 15

A point object emitting two wavelengths of light will produce a double retinal image which gives rise to perception of a double object, the condition is _____??

Answer 15

Chromatic diplopia

Question 16

What’s an illusion in which differently colored object located at the same viewing distance appear to lie at different distances?

It’s and effect of ____ combined with binocular vision

Answer 16

Chromosteropsis

TCA

BLUE written in red ink on a blue background

Question 17

___ color has an apparent location at a SHORTER distance than the color ___. Which is apparently FURTHER away

Answer 17

RED CLOSER

BLUE FAR AWAY!!!!

Question 18

What order aberrations do optometrists fix? What % of all aberrations are this order?

Answer 18

LOWER (defocus and astigmatism)

90%

Question 19

Correcting monochromatic and chromatic aberrations, this provides a ______ improvement in constraint sensitivity

Answer 19

LARGE

Question 20

When only monochromatic aberrations are corrected, contrast sensitivity increased by a factor of____

Answer 20

2!!!!!

Question 21

When only monochromatic & chromatic aberrations are corrected, the contrast sensitivity of the eye is improved by a factor
of ____to _

Answer 21

3.2 to 5

Question 22

Chromatic difference of position induces___ which affects image contrast

Answer 22

Phase shifts

Question 23

LCA of they eye doesn’t change; T/F

Answer 23

TRUE

Question 24

Dispersion of water varies about ___% across

Answer 24

1

Question 25

Expand the abbreviations

CD-R
CDF
CDP
CDM
LCA
TCA

Answer 25

..