1. QOD: What happens to the rays with a diverging lens?
Mirrors & Lenses
QOD: What happens to the rays with a diverging lens?

2. Law of Reflection
the angle of incidence is equal to the angle of reflection

3. Mirrors Plane mirror – flat mirror image produced is upright (virtual)
image is the same size as the object
image distance = the object distance

4. Converging mirror – Concave (caves inward)
F – focal point is the point where parallel rays appear to meet after reflecting from a mirror.
f - focal length - the distance from focal point to mirror. f is always + for converging mirror and – for diverging mirror
C – center of curvature
R – radius of sphere
f = R/2

5. Diverging mirror – Convex (curves out)
Light from a larger area is focused, thereby allowing you to see a wide area.
Used for security purposes in stores and on side mirrors in cars.

6. Refraction
Refraction - the bending of the path of a light wave as it passes across the boundary separating two different media.
Caused by the change in speed experienced by a wave when it changes medium.
The amount of bending is called the index of refraction (n)

7. Light traveling from a fast medium to a slow medium will bend toward the normal
Light traveling from a slow medium to a fast medium will bend away from the normal

8. Lenses
A lens is a carefully ground or molded piece of transparent material which refracts light rays in such a way as to form an image.
2 Types: Converging and Diverging

9. Converging Lens Thick in middle and thin at edges
Increases the angle of view (more light is brought into focus) and therefore magnifies objects that are between the focal point and the lens

10. Diverging Lens Thick at edges and thin in the middle
Image is always reduced
Used to correct near-sightedness

11. LASER Light Amplification by Stimulated Emission of Radiation
Explanation

12. Diffraction
Any bending of a wave by means other than reflection or refraction
A wide opening compared to wavelength produces little or no diffraction
As the opening gets smaller, diffraction becomes more pronounced

13. Diffraction Grating
A diffraction grating is used to separate light into its’ component wavelengths
The tracks of a CD act as a diffraction grating, producing a separation of the colors of white light.

14. Single Slit
Double Wide Slits
Double Thin Slits