1. Judge last week: “Pi is not copyrightable”
Announcements 3/21/12
Prayer
Foxtrot
Judge last week: “Pi is not copyrightable”

2. Reading Quiz
The _________ approximation is a special case of the _________ approximation:
Fraunhofer; Fresnel
Fresnel; Fraunhofer

3. Reading Quiz
The Fraunhofer approximation describes what happens in the:
“far field”
“near field”

4. Reading Quiz
The Fraunhofer diffraction pattern from a rectangular aperture involves:
Bessel functions
sinc functions

5. Fraunhofer Approximation

6. Fraunhofer as 2D Fourier Transform

7. Narrow slit formula

8. Rectangular slit formula

9. Square slit plots
Square slit:
Zooming in…

10. Rectangular slit plotsy
Rectangular slit: y width = 2 x-width
Zoomed in… x
Thought question: Which way is x and which way is y? x y a. b. y x

11. Rectangular slit to the extreme
Rectangular slit: y width = 25 x-width
Guesses?

12. Double slit (via convolution theorem)
plotted for separation = 4 slit width