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Flashcards in Single Slit Diffraction Deck (33):
1

Change in direction of propagation of light NOT due to reflection of refraction

Diffraction

2

The deviation from rectilinear propagation that occurs when light advances beyond an obstruction

Phenomenon of diffraction

3

Can we use snellls law to predict diffraction

No

4

Diffraction at the edge of an aperture does what to images

Blurs images of objects

5

What proved light is a wave?

Diffraction

6

What is Huygens principle

All points on a wavefront can be considered as point sources for the production of spherical secondary wavelets, and at any later time the new wavefront position in the envelope (or surface of tangency) to these secondary wavefronts

7

What is fresenels expansion on Huygens principle

For light in the same bundle (waves from the same point source) the secondary wavelets undergo mutual interference. Interfere constructively and destructively

8

What is the ripple effect in the diffraction pattern due to?

The constructive and destructive interference of the secondary wavelets

9

When a single slit is vertical, the waves are diffracted _______

Horizontally

10

When a single slit is horizontal, the waves are diffracted ______

Vertically

11

When a vertical slit is placed against a horizontal slit of the same width, the combo forms ________

A square aperture

12

When a circular aperture is illuminated by a monochromatic plane wave, the waves are diffracted_________

Equally in all directions

13

Wavelength of spruce equal to or larger than width of the slit (lambda > a), forms _________

Diffraction pattern

14

For diffraction to occur, what is the relationship of d and a?

D should be larger than a

15

Path difference in single slit diffraction

asin(theta)=m(lambda)

16

What are the two types of diffraction?

-fresnel (near field) diffraction
-Fraunhofer (far-field) diffraction

17

Fresnel (near field) diffraction

The source of light and the screen are at finite distance from the diffraction aperture

Can be converging or diverging, but not collimated

18

Fraunhofer (far field) diffraction

The source of light and the screen are at an infinite distance from the diffraction aperture

Can be collimated

19

Which type of diffraction is easy to observe and calculate the intensity distribution

Fraunhofer (far field) diffraction

20

Bright in the center of a shadow, ex. Floaters in the eye

Poisson spot

21

Near field diffraction

Fresnel diffraction

22

Far field diffraction

Fraunhofer diffraction

23

Finite distance from slit to screen

Fresnel diffraction

24

Infinite distance from slit to screen

Fraunhofer diffraction

25

Converging or diverging wave

Fresnel difffraction

26

Plane waves

Fraunhofer diffraction

27

Difficult to observe and calculate

Fresnel diffraction

28

Easy to observe and calculate

Fraunhofer diffraction

29

Diffraction patterns vary with distance (slit to screen)

Fresnel diffraction

30

Insensitive to distance changes (maintains same angular relationship)

Fraunhofer diffraction

31

Which type of diffraction yields a poisson spot?

Fresnel diffraction

32

Combined effect of 2 slits and single slit interference

With 2 slits, not only will you see diffraction patterns due to individual single slits, but also interference patterns due to the waves coming from different slits

33

The diffraction pattern acts as ________--, that _____________

-Envelope
-that controls the intensity of the regularly spaced interference maxima