Evans SPH 3U1
Physics Grade 11
Unit 3: Light and Optics
Note 8: Applications of Lenses
Reference: Chapter 11.8
Eye Defects and Corrections:
Have students complete the following:
1) Identify what hyperopia and myopia are.
2) Draw a ray diagram to illustrate hyperopia. Draw another ray diagram to illustrate myopia
3) Draw a ray diagram to illustrate how either a converging or diverging lens can correct the problem.
|
Problem |
Why it’s a problem |
Corrective lens |
|
Hyperopia (far-sightedness) |
Image comes to a focus behind the retina |
Converging lens |
|
Myopia (near-sightedness) |
Image comes to a focus in front of the retina |
Diverging lens |
:
Multiple Lenses:
The image of the first lens is the object for the second lens.
The first lens is called the objective and it creates a real inverted image. This image falls inside the focal length of the second lens (eyepiece, ocular).
The second image is a virtual image and larger than the real image.
Page 392 #1
Page 395 # 60, 61
Page 391 # 6, 9, 11