1. HW #4, Due Sep. 21
Ch. 2: P28, PH8, PH16
Ch. 3: P3, P5

2. Lecture 8 (chapter 2 continued)
Quick Review:
Refraction in Nature (Mirages, Halos, Rainbows,..)
This Lecture:
Chapter 3 (Lenses and Mirrors)

3. Mirages, Rainbows, Halos, Sun Dogs….
Next
Refraction in Nature
Mirages, Rainbows, Halos, Sun Dogs….

4. Mirages and Atmospheric Distortions
sunset
mirage

5. Mirage

6. Dispersion Refractive Index varies with Wavelength : n()
Dispersion in a prism
* Prism Refraction
refraction & refl.
dispersion

7. Rainbow

8. Rainbow *Rainbow http://www.phy.ntnu.edu.tw/java/Rainbow/rainbow.html
rain drop

11. Ice Crystals

12. Sun Dogs

17. Halos

19. 22 degree halo

20. 22 degree halo

21. 46 degree halos

22. Chapter 3 Mirrors and Lenses
Read , 3.2, 3.3 (A, B, C* , D), 3.4, 3.5**
* Anamorphic Art
** Aberrations

23. Flat mirror revisited
virtual
image
Read Text about the Kaleidoscope

24. (simply apply the law of reflection)
Spherical Mirrors
Where is the image?
What is the field of view?
Ray Tracing
(simply apply the law of reflection)

25. Reflection in Curved Mirrors
Convex and Concave
Mirrors

26. axis O C F center focal point
Paraxial Rays: Rays that are close to the axis

27. Ray Rules for a Convex Mirror
Ray Rule 1: All rays incident parallel to the axis are reflected so
that they appear to be coming form the the focal point, F.
Ray Rule 2: All rays that (when extended) pass through center C
are reflected back to themselves.
Ray Rule 3: All rays that (when extended) pass through F are
reflected back parallel to the axis.

28. C F O 1 C F O 3 C F O 2

29. Locating the Image Mirrors *Concave Mirrors
*Concave Lens: virtual image
*Convex Mirrors
spherical aberration

31. “Hand with Reflecting Globe”
M. C. Escher,
“Hand with Reflecting Globe”
Fig 3.9

32. Concave Mirror
axis O C F
center
focal point

33. Ray Rules for a Concave Mirror
Ray Rule 1: All rays incident parallel to the axis are reflected so
that they appear to be coming form the the focal point, F.
Ray Rule 2: All rays that (when extended) pass through center C
are reflected back to themselves.
Ray Rule 3: All rays that (when extended) pass through F are
reflected back parallel to the axis.

34. *Concave Mirrors

35. Lenses

36. *Magnification (Magnifying Glass)
* Lens Action (Many Applets)
principle rays
*Thick Lens (Spherical Aberration)

37. Fresnel Lenses