1. Dr. Murty Wizard of Light
The OPTRICKS
Suitcase
Optics is Light Work!
Dr. Murty Wizard of Light
OPTRICKS
Suitcase

2. What is Light?
Light is radiation we can see

3. Optics is the Science of Light
Where are optics in everyday life?
Cameras
Eyes
Glasses
Lasers
Fiber Optics
Telescopes
Displays

4. Optics is the Science of Light Basic Optics
Mirror
Lens

5. First, a little chemistry…

6. Silicon Makes Mirrors and Lenses
Silicon plus Oxygen is
Silicon Dioxide
Si + O2  SiO2
Glass is crystalline SiO2
Sand is amorphous SiO2
It has no shape

7. When you look through a lens, how do you see clearly?
Focus!

8. What is my favorite kind of lens?
Fresnel Lens!

9. What is a Fresnel Lens?
FUN!

10. What is a Fresnel Lens?

11. Where are Fresnel Lenses Used?
Lighthouses
RV rearview lenses
Overhead projectors
Intraocular implants
Cell phone cameras
Solar-thermal energy reflectors
Aircraft carrier landing beacons

12. Camera Optics Detector (sensor or film) Computer Lenses
© Stephen Sweet #

13. Eyeball Optics
Detector = Retina
Computer?
Lenses = Lens + Cornea

14. Your Brain is Your Computer!
The striate cortex in the back of your brain interprets images from your eye.

15. Light is an Electromagnetic Wave
Electricity
Magnetism
Every wave has Magnitude, Direction, and Length.

16. Light is an Electromagnetic Wave
Magnitude  Size of each vibration  Power
Direction  Vibrations follow a path  Polarization
Length  Separation between vibrations  Color
What vibrates like a wave?
Slinky !

17. Light is an Electromagnetic Wave
Magnitude  Size of each vibration  Power
Direction  Vibrations follow a path  Polarization
Length  Separation between vibrations  Color

18. Light is an Electromagnetic Wave
Magnitude  Size of each vibration  Power
Direction  Vibrations follow a path  Polarization
Length  Separation between vibrations  Color
dim light
small vibrations
Bright Light
LARGE VIBRATIONS

19. Light is an Electromagnetic Wave
Magnitude  Size of each vibration  Power
Direction  Vibrations follow a path  Polarization
Length  Separation between vibrations  Color

20. Vibration Direction is Polarization
Horizontal Linear Polarization
Vertical Linear Polarization
Left Circular Polarization
Right Circular Polarization

21. How is Polarization Used? Polarized Sunglasses Block Glare
polarizer transmission
vertical
the same
polarizer transmission
horizontal
horizontal
glass surface

22. How is Polarization Used? 3D Displays
howstuffworks.com
Two cameras record the movie, one camera for each eye
Both camera’s images are superimposed on the screen
The left eye movie is projected with horizontal polarization
The right eye movie is projected with vertical polarization
Polarizing glasses block horizontal polarization from the right eye and block vertical polarization from the left eye

23. How is Polarization Used? Photoelasticity
Photoelasticity measures stress in plastics because different colors bend through the plastic at different angles.
in a liquid crystal display (LCD)
through a plastic airplane window

24. Light is an Electromagnetic Wave
Magnitude  Size of each vibration  Power
Direction  Vibrations follow a path  Polarization
Length  Separation between vibrations  Color

25. Wavelength is Color

26. Wavelength is Color
RED
ORANGE
YELLOW
GREEN
BLUE
VIOLET

27. Lenses Magnify Mixed Colors
Magic Dots
Color prints are made by mixing only a few pigments (ink) to make many colors of the rainbow
Look closely at a color print or a color display with your lens, you will see tiny dots of pigment
Color displays are made by mixing only a few lights to make many colors of the rainbow

28. Magnify Your Optricks Card At a distance…

29. Magnify Your Optricks Card Closer…

30. Magnify Your Optricks Card Tiny Dots of Color Appear!

31. Magnify a Cell Phone Display At a distance…

32. Magnify a Cell Phone Display Closer…

33. Magnify a Cell Phone Display Green + Red = Yellow!

34. Magnify a Cell Phone Display Yellow!
green
yellow

35. Magnify a Cell Phone Display Mixing Blue with Green…
cyan

36. Magnify a Cell Phone Display Blue + Green…makes Cyan

37. Magnify a Cell Phone Display Cyan!
blue
cyan

38. Magnify a Cell Phone Display Red + Blue = Magenta … and Purple?

39. Magnify a Cell Phone Display Dimmer Red turns Magenta to Purple

40. Magnify a Cell Phone Display What about White?
white text

41. Magnify a Cell Phone Display Red + Green + Blue = White!

42. Three Colors Mix to form other colors Pigments Subtract, Lights Add
Color prints mix pigments (Cyan, Yellow, and Magenta) to subtract color from a white sheet
Color displays mix lights (Red, Green, and Blue) to add color to a black screen

43. Magic Patch Liquid Crystal “Magic Patches” change color with heat
These are liquid crystals (LCs) that selectively reflect different colors at different temperatures
Temperature changes the ordered structure of the LCs, like the students in the images below
Engineers cut LCs into tiny pieces known as pixels (picture elements)
Tiny LC pixels are arranged in a grid and individually heated to make LC displays (LCDs) for computers, watches, cell phones, etc.

44. Cholesteric Liquid Crystals
Warm
Cold
Yellow to Orange to Red to Black
Green to Blue

45. Polarizers + Liquid Crystals Make Displays

46. Rainbow Peepholes® Diffraction Gratings
The grid of bumps in the plastic diffract the colors of the white light into the visible spectrum.

47. Rainbow Peepholes® Diffraction Gratings
Colors are mixed together to make many types of lights.
Lights are separated into its constituent colors by diffraction

48. Diffraction Incandescent (tungsten halogen) Light

49. Diffraction Incandescent (tungsten halogen) Light

50. Diffraction Compact Fluorescent Light (CFL)

51. Diffraction Compact Fluorescent Light (CFL)

52. Diffraction Sodium Vapor Street Light

53. Diffraction Sodium Vapor Street Light

54. Diffraction LED Flashlight

55. Diffraction LED Flashlight

56. Diffraction Gas-Discharge Lamps (“Neon” Lights)

57. Diffraction Atomic Emission Spectra

58. Our sponsors and supporting organizations:

59. Thank You for Paying Attention Always Ask Questions!
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