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Flashcards in Light Scatterind Deck (29):
1

Scattering of light is caused due to the ____________ in a medium

In-homogeneities

2

Defuse diffraction

Air and medium with high index

3

What are the two types of scattering?

Incoherent
Coherent

4

Conditions for incoherent scattering

White light
Particles far apart

5

Incoherent scattering depends on

Size of particles
Distance between particles
Strength of interaction

6

What determines the strength of the interaction in incoherent light scattering?

Refractive index and absoprtion strength

7

When the scattering particles are smaller than the wavelength

Rayleigh scattering

8

What does rayleigh scattering profile show?

Forward and backward scatter (scatter in all directions)

9

Rayleigh has a strong _________ dependence

Wavelength

10

What kind of wavelength scatters more in rayleigh scattering?

Shorter, blue

11

Rayleigh scattering is an ____________, as the scattered photons energy do not change.

Elastic scattering

12

Light going to a denser medium changes the _______

Wavelength

13

For rayleigh scattering, the intensity of the scattering blue light it _______ times than that of the scattered red light

3.3

14

How do you calculate relative scattering intensity?

(Lambda1/lamda2)^4

15

How much brighter is LED than sodium light?

3x

16

The bluer the light, the more the light scatters and the larger the area of the ______

Glare

17

Downside of LED?

Affects astronomical observations, and causes harmful effects on he wild plants, and animal population (light pollution)

18

Photopic sensitivity

Day time sensitivity, when rods are sensitive

19

What does blue light disrupt?

Circadian rhythm, disrupts melatonin

20

Mesopic vision

Dawn/dusk
Rods and cones become active

21

Scotopic sensitivity

Peak sensitivity at about 500nm

22

When the scattering particles are larger than the wavelength of light

Mie scattering

23

What are the dominant causes of mie scattering?

Geometrical optics process of reflection and refraction are the dominant causes of the mie scattering

24

Scattering profile of mie scattering

Stronger forward scattering

25

Mie scattering theory applies for particles to both ________ and _______

Absorb and scatter, rayleigh is only scatter

26

Techniques based on mie scattering theory are used in several studies in the understanding of

Optical properties of biological tissues like skin, brain, bone, other soft tissues, other fibrous tissues and fatty tissues, and even blood cells

27

What are some examples of Rayleigh's scattering

Bluish smoke from fire and cigarette

28

Why does cigarette smoke appear blue but when its exhaled, becomes white?

Its Rayleigh scattering first, then when it is inhaled, it mixes with the moisture particles and becomes mie scattering

29

The more the light is scattered, the less the wavelength dependence of the ________

Scattered intensity