1. Chapter 18
Mirrors & Lenses

2. Calculate the angle of total internal reflection in ignoramium (n = 4

3. Smooth surfaces that reflect light waves
Mirrors
Smooth surfaces that reflect light waves

4. Mirrors have been used for thousands of years by polishing metal

5. Mirrors
Mirrors producing sharp & well defined images were developed by Jean Foucault in 1857

6. Mirrors
Jean Foucault developed a method to coat glass with silver making excellent mirrors

7. The source of the spreading light waves being observed
Object
The source of the spreading light waves being observed

8. A reproduction of an object observed through lenses or mirrors
Image
A reproduction of an object observed through lenses or mirrors

9. When you look into a mirror, you see an image of yourself

10. Plane Mirror
Mirrors on smooth flat surfaces that give regular reflection and good images

11. All reflect waves are parallel producing a good image
Regular Reflection
All reflect waves are parallel producing a good image

12. Diffuse Reflection
Reflect waves from a rough surface bounce in all directions producing a poor or no image

13. Objects & Images
Objects & images are represented by arrows as to distinguish the top from the bottom

14. do di ho hi
image
object
di = do
hi = ho

15. Light rays focus on a point behind the mirror
Virtual Image
Light rays focus on a point behind the mirror

16. Virtual Image
Virtual images are erect: image & object pointing in the same direction

17. Concave Mirrors
Light rays are reflect from the inner (caved in) surface part of a hollow sphere

18. Parallel light rays converge when reflected off of a concave mirror
Concave Mirrors
Parallel light rays converge when reflected off of a concave mirror

19. Concave Mirrors F: focal point F C C: center of curvature
Principal axis

20. Focal Point
Point at which parallel light rays converge (reflecting from a concave mirror in this case)

21. The distance between the mirror or lens and the focal point
Focal Length (f)
The distance between the mirror or lens and the focal point

22. The center of the sphere whose inner surface makes the concave mirror
Center of Curvature
The center of the sphere whose inner surface makes the concave mirror

23. Concave Mirrors

24. Concave Mirrors

25. Concave Mirrors

26. Concave Mirrors

27. Concave Mirrors

28. Concave Mirrors

29. Concave Mirrors
do > C: di < do hi < ho

30. Concave Mirrors

31. Concave Mirrors

32. Concave Mirrors

33. Concave Mirrors

34. Concave Mirrors

35. Concave Mirrors
do = C: di = do hi = ho

36. Concave Mirrors

37. Concave Mirrors

38. Concave Mirrors

39. Concave Mirrors

40. Concave Mirrors

41. Concave Mirrors
do < C: di > do hi > ho

42. Concave Mirrors

43. Concave Mirrors

44. Concave Mirrors

45. Concave Mirrors

46. Concave Mirrors

47. Concave Mirrors

48. Concave Mirrors
do < f: di = BM hi > ho

49. Problems with Concave Mirrors:

50. Draw Ray Diagram & Determine Type of Image

51. Draw Ray Diagram & Determine Type of Image

52. Draw Ray Diagram & Determine Type of Image

53. Draw Ray Diagram & Determine Type of Image

54. Draw Ray Diagram & Determine Type of Image

55. Mirror & Lens Formula
f do di = +

56. f = focal length do = object distance di = image distance
Mirror & Lens Formula
f = focal length
do = object distance
di = image distance

57. Magnification Formula
hi di
ho do =

58. Magnificaton hi ho
M =

59. Magnification Formula
M = magnification
ho = object height
hi = image height

60. Problems

61. A 5.0 cm object is placed 25.0 cm from a concave mirror with a focal length of 10.0 cm. Calculate: di, hi, & M

62. A 250 mm object is placed 25 cm from a concave mirror whose center of curvature is 250 mm. Calculate: di, hi, & M

63. A 15 cm object placed 75 cm from a concave mirror produces an image 50
A 15 cm object placed 75 cm from a concave mirror produces an image 50.0 cm from the mirror. Calculate: f, hi, & M

64. A 50.0 mm object is placed 0.25 m from a concave mirror with a focal length of
50.0 cm. Calculate: di, hi, & M

65. Light rays are reflected from the outer surface part of a sphere
Convex Mirrors
Light rays are reflected from the outer surface part of a sphere

66. Parallel light rays diverge when reflected off of a convex mirror
Convex Mirrors
Parallel light rays diverge when reflected off of a convex mirror

67. Convex Mirrors
do < f: di = BM hi < ho

69. Spherical Aberration
The parallel rays reflected off of the edges of a spherical concave mirror miss the focal point, blurring the image.

70. This is corrected by using a parabolic concave mirror
Spherical Aberration
This is corrected by using a parabolic concave mirror

71. Lenses
Transparent material that allows that light to pass through, but refracts the light rays

72. Caved in lenses where the center is thinner than the edges
Concave Lenses
Caved in lenses where the center is thinner than the edges

73. Bulging lenses where the center is thicker than the edges
Convex Lenses
Bulging lenses where the center is thicker than the edges

74. Parallel light rays diverge when passing through a concave lens
Concave Lenses
Parallel light rays diverge when passing through a concave lens

75. Parallel light rays converge when passing through a convex lens
Convex Lenses
Parallel light rays converge when passing through a convex lens

76. Convex Lenses

77. Convex Lenses

78. Concave Lenses

79. Chromatic Aberration
The parallel rays passing through a lens are refracted at the edges more so than at the center dispersing the colors

80. Corrected through lens coating or double lens effect
Chromatic Aberration
Corrected through lens coating or double lens effect

81. Achromatic Lens
A lens that has been made so that there is no chromatic aberration

82. Find the
image

83. Eye Glasses Concave lenses correct nearsightedness
Convex lenses correct farsightedness

84. Sees close-up well, but cannot see distances very well
Nearsighted
Sees close-up well, but cannot see distances very well

85. Sees distances well, but cannot see close-up very well
Farsighted
Sees distances well, but cannot see close-up very well

86. A 150 cm object placed 75 cm from a concave mirror produces an image 250 cm from the mirror. Draw & Calculate: f, hi, & M

87. A 250 cm object placed 1.5 m from a convex lens with a focal length 50.0 cm from the mirror. Calculate: di, hi, & M

88. A 350 cm object placed 150 cm from a convex mirror with a focal length -75 cm from the mirror. Calculate: di, hi, & M

89. Draw Ray Diagram & Determine Type of Image
Mirror

90. Draw Ray Diagram & Determine Type of Image

91. Draw Ray Diagram & Determine Type of Image

92. Draw Ray Diagram & Determine Type of Image
Mirror

93. Draw the Ray Diagram

94. Draw the Ray Diagram

95. Convex Lenses