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Flashcards in turning Point Questions Deck (63):
1

Diffraction is a change in direction of propagation due to

Edge phenomenon

2

Fresnel, secondary wavelets undergo mutual interference, true or false

True

3

Constructive interference in a single slit diffraction

asin(theta)=m (lambda)
A=slit width

4

What is the type of diffraction, if the source of light and the screen are at finite distance from the diffraction aperture?

Fresnel

5

In the single slit diffraction, when the aperture size 'a' decreases, what happens to the diffraction pattern?

Spreads out

6

What os the type of diffraction, if the source of light and the screen are at a finite distance from the diffraction aperture

Fresnel diffraction

7

The smallest letters that a person with 20/2 snellen acuity can resolve have detail that subtends at angle of ____

1'

8

What happens to diffraction image point in a phase plate when the alternate zones are phase shifted by 180 degrees?

Brighter

9

When a diffractive structure (phase plate) is embedded on one side of the refractive lens, the lens is called

Hybrid

10

In the diffractive multifocal lens, when m=0 the power of the lens is

Zero

11

In a diffractive multifocal lens, the first order diffraction generates the _____ power

Add power

12

Wearing multifocal lens causes some patients see shadows formed onto their retina. This condition is called _____

Negative dysphotopsia

13

The strength of the iridescence in a mollusk shell is due to _____ and _______

Groove density and surface quality

14

Fresnel' lans increases the luminosity of the lighthouse lamp by a factor of _____

4

15

The energy allocation, in diffractive multifocal lens, between 0th order and 1st order is known as _____

Diffraction efficiency

16

What causes the interference pattern to form 3d holography image

Phase difference

17

While using a coherent source to view a recorded holography image, which of the diffraction orders does one view the image?

-1 order

18

In a typical human eye when the pupil size increases, which one of the following will increasingly affect vision

Aberration

19

Diffraction is a change in direction due to

Edge phenomenon

20

What equation is for constructive interference in a single slit diffraction

Asin(theta)=m(lambda)

21

Which of the scattering will happen when the particles are smaller than the wavelength of the light

Rayleigh

22

What is the scattering profile of Mie scattering

Mostly forward

23

Bluer the light, more the light scatter

True

24

For a healthy non-cataractous eye, the intraocular scatter increases by 2x at the age of ____ compared to young eyes

65

25

In the blue/blue-green eyes, intraocular scatter is caused by pigmentations in the scleral wall, iris and ________

Fundus

26

Which of the following refractive surgery techniques causes an increase of intraocular scatter by a factor of 4?

RK

27

Corneal transmittance is dependent on

Wavelength

28

When wave 1 and wave 2 are in phase, but wave 1 travels an extra distance ( or path difference) equal to 1 wavelength, then this interference is called

Constructive interference

29

Condition for destructive interference is when the path difference between two waves is equal to (m is an integer, n is the refractive index, lambda is the wavelength)

(M+1/2)/lambda

30

In the condition for forming bright fringes, dsin(theta)=mlambda, 'd' represents the distance between the 2 slits and the screen

False

31

A He-Ne laser beam (lambda=632.8nm) is incident on double slits of separation 0.8mm. On a screen located 6m from the slits, how far is the third order maximum from the center of the interference pattern?

14.2mm

Y=m(lambda)L/d

32

Two conditions for getting an interference fringe in youngs double slit experiment is

Monochromatic light and mutual coherence

33

Thin film interference is based on the division of amplitude, true or false

True

34

Which is commonly used single layer anti reflection coating material?

Magnesium fluoride

35

Single layer anti reflection coating reduces light reflection from 4.3% to about _______

1.5%

36

How much does a multilayer anti reflection thin film coating reduce the light reflection to about ?

0.5%

37

The minimum thickness of an anti reflecting thin film on glass is _______ of the wavelength in the thin film

Quarter

38

Diffraction is a change in direction of propagation due to

Edge phenomenon

39

According to fresnel, whom expanded on huygen's principle, proposed that that the secondary wavelets would undergo mutual interference

True

40

What is the condition for constructive interference in a single slit diffraction

Asin(theta)=m(lambda)

41

In the single slit diffraction, when the aperture size 'a' decreases, what happens to the diffraction pattern

Spread out

42

What is the type of diffraction, if the source of light and the screen are at a finite distance from the diffraction aperture

Fresnel diffraction

43

The smallest letters that a person with 20/40 acuity can resolve have a detail that subtends at angle of ____

2'

44

An optical device that blocks alternate zones is called

Zone plate

45

What happens to diffraction image point in a pjhase plate when the alternate zones are phase shifted by 180

Brighter

46

Incoherent scattering depends on what two conditions?

Particle size and distance between two particle ( it should be greater than coherence of the light)

47

When the particles are smaller than wavelength of light, what type of scatterin

Rayleigh

48

What is the scattering profile of rayleigh

All directions

49

Shorter wavelength scatters more light, true or false

True, blue

50

Corneal transmittance is dependent upon

Wavelength

51

What is the effect of light transmission to blue rims for red light

1% because of absence of melanin

0.2% for green light

52

What is the 3rd component for blue and green eyes in scatter other than scleral wall and iris?

Fundus

53

As you age for a healthy non cataractous eye, what is the increase in scatter for age 77?

3x

54

What percentage of horizontally polarizaed light gets transmitted if a vertically polarized filter is tilted 5 degrees?

Cos^2(theta)
Cos^2(5)
8%

Make sure to change to radians in calculator!!

55

For light in air incident on high index plastic of 1.66 refractive index, what is the incident angle of polarization

Brewsters angle
Tan(theta)=n2/n1
53.93 degrees

56

The sunlight glare can pass through a polarized filter when the transmission axis is _______

Horizontal
-if you hold it vertical, you will stop the sunlight scatter

57

The waggle dance of the bee communicates the direction of food and _____

Location

58

Formed dichroism is based on specific property of material which is ______

Structure

59

When light travels in birefringent material, a relative delay between transmission is called

Phase retardation

60

What is the slow ray in polarization called

Extraordinary ray

61

What is the fast ray in polarization called

Ordinary ray

62

Due to birefringence of cornea and lens, it changes from linear polarization to ______

Elliptical

63

Haidenger's brush apparatus could be used to diagnose mblyopia due to what

Eccentric target