How do we see?

Throughout the history of early Science and Mathematics, many Muslims made great progress in these fields, forming a foundation which we continue to study even today.

One of these founding fathers of scientific learning, was a man named al-Hasan Ibn al-Haytham, born in Iraq almost a thousand years ago. He is said in fact, to be one of the first scientists, famous for discovering how vision works.

To cut a long story short, he was sat in his dark room one day, when a small hole let through some light. He spotted projected onto his wall an upside down image of outside.
After making further observations through scientific experimentations, he concluded that light travels in straight lines, and this light coming through the hole and projecting onto the wall demonstrated how vision works.

We have begun a project with some other home schooled girls about sight, starting with a brief study of Ibn al-Haytham, since he was the first to make this amazing discovery to explain how we see.

One of the things Ibn al-Haytham did, was make a small box, which has become known as the camera obscura. One side of the box was a thin sheet of paper, with a small pin hole in the side directly opposite. He used this box to test his ideas, directing the pin hole towards three lit candles, allowing him to see projected onto the paper side, an upside down image of the light!

You can find many instructions online to make your own camera obcsura; I used the one given in the 1001 inventons teachers pack.

You need to be careful when viewing the candle, as the pin hole really needs to face the candle light, and ideally the darker the room the better.
You are not going to see a crystal clear picture, however you will see an upside down image of the candle light shape.
I found that we had to either cup our hands around our camera obscura viewing and eye, so that no extra light would get into our vision, or wait until after margin and view with all the lights out. But it does work Alhamdulillah!

To prepare our learning, I used 1001 Inventions: Muslim Heritage in our world, which provides a look at contributions made in various areas including home, school and medicine. National Geographic also released earlier this summer a small book for children about Ibn al-Haytham. Although simple in writing, this was a great resource and certainly helped my children bring the story of Ibn al-Haytham to life.
There is also a short documentary I believe produced by Al-Jazeera over on youtube, which shows how Ibn al-Haytham's discovery of light works and shows you how a room in your house can be made into your very own camera obscura to view outside! (discussion about Ibn al-Haytham begins from about 6min 30 sec)

If you are interested in making your own study, to accompany the 1001 Inventions book, there is a free teacher guide PDF, which will help you plan a lesson and activities to go along with your learning, as well as a website dedicated to Ibn al Haytham.