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Flashcards in Diffraciton Grating Deck (27):
1

When the central maxima of one image falls on the first minimum of another image, the images are said to be just resolved. This limiting condition of resolution is known as

Rayleigh's Criterion

2

Rayleigh's criterion equation?

Theta=1.22 lambda/d

Smallest resolvable angle
Limiting angle of resolution

3

Snellen acuity is equal to the what?

Reciprocal of the minimum resolvable angular detail, expressed in minutes

4

How do you convert angles to minutes

X 180, divide by pi

5

According to ISO standard, R. E. > ________ is an acceptable image quality standard for industry product release

60%

6

To remove the rings around the central maxima and concentrate energy in the central maxima is called __________

Apodization

7

At the center of the anodized circular pupil, the intensity transmission is ______

100%

8

Diffraction pattern and apodization

For a clear circular pattern, airy's disk contains 84% of the intensity in the diffraction pattern

9

Gaussian filter

86% of the intensity is inside the circle
-there are no rings, only smooth illumination fall off

10

What kind of filters do pupils act like?

Gaussian filters (apodized)

11

What is the stile crawford effect?

The luminous efficiency of rays entering at the center of the eye pupil is greater than the luminous efficiency of the rays entering through the edge of the pupil

12

Despite its retinal origins, the stiles crawford effect is sometimes modeled optically as a filter placed in front of the eye, in which the density of the filter increases from the center toward the edge of the filter, this is known as _________

Apodization

13

What influences the VA and visual performance of the human eye?

Stiles crawford apodization

14

Distance between maxima and 1st order minima is ________. This number also tells us how many maxima there are as well

D-2

15

A _____________ consists of many slits with a very small slit separation

Diffraction grating

16

Efficiency drops with ___________ number of slits

Higher

17

Transmission grating

-acts a laser beam splitter
-less sensitive to polarization
-less sensitive to alignment
-efficiency reduces with higher wavelength

18

CDs are an example of what?

Reflection diffraction grating

19

A diffraction grating that is designed to channel light away from the central maximum (oth order) into 1st or 2nd order maximums

Blazed grating

20

Angle at which the efficiency is maximum

Blazing angle

21

Optical device that blocks alternate zones

Zone plate

22

Diffraction image grating creates inwardly bending spherical diffracted wave

Point image

23

Central order (0th) goes though

Straight

24

1st order posting image is at

F2

25

2nd order point image is at

F2/2

26

3rd order point image is at

F2/3

27

Fresnel zone plate blocks wave that contribute to destructive interference at the diffraction max, making the image formation much _______

Dimmer