1. Lenses
Physics Mr. Berman

2. What phenomenon is evident in lenses?

3. Basic Types of Lenses
Convex
Concave

4. Convex Lens

5. Concave Lens

6. Type of Image
Real or Virtual
Enlarged or Reduced
Erect or Inverted

7. Convex Lens f C
Center

8. Ray Diagram for Convex Lens
Principal Axis

9. Rules for Ray Diagrams for Convex Lens
A parallel ray refracts through the focal point.
A ray through the center of the lens continues straight.
A ray coming through the focal point, refracts parallel to the principal axis.

10. http://higheredbcs. wiley

11. Summary for Convex Lens
When the object is:
Beyond 2F
At 2F
Between 2F and F
At F
Between F and lens
Then the image is:
Between 2F and F
At 2F
Beyond 2F
No image
Virtual image

12. Sign Convention do + object distance
di   +   real image, other side of lens
di    -   virtual image, same side as object
hi + erect image
hi - inverted image
f     +   converging lens (convex)
f     -    diverging lens (concave)

13. Magnification M = hi = -di ho do
Note: When magnification is <0, the image is inverted.

14. Lens Equation
1 = 1 + 1
f do di

15. Concave Lens
Object
Image

16. Summary for Concave Lens
Always:
Virtual, reduced, upright image

17. http://bcs. wiley. com/he-bcs/Books