1. The History of Light & Optics
Lesson 1 - The Histroy of Light & Optics
The History of Light & Optics

2. Check & Reflect Answers
1. What did Ptolemy discover about light?
Ptolemy was the first to discover that light could bend when it travels from one medium to another with different densities (i.e. from air to glass).
2. What was Pythagoras's theory of how we see?
Pythagoras believed that light “came out of our eyes” and that was how we were able to see object in front of us.
3. What was the problem with Pythagoras’s theory?
His theory could not be true otherwise we should be able to see in the dark

3. Check & Reflect Answers
4. What did al-Haytham try to explain?
al-Haytham was the first to properly explain how light was reflected to our eyes and that our eyes received that light allowing us to see.
5. Based on Michelson’s measurement of the speed of light. If the distance from the sun to the earth is km, how long does it take light to travel from the sun to the earth?
km ÷ km = 499 seconds
seconds
499 seconds = 8 min & 19 sec

4. The Big Idea!!! We can see because…
Light is emitted from a light source
Light then travels to & strikes an object
Light is reflected off of that object to our eyes
Our eyes gather that light to make an image out of it

5. We Can See Because…