Draft: this lesson was written with AI help and has not yet been read by a human editor.
1 What your class asks
This lesson asks you to identify the sensory organs and the devices that make use of the properties of light and sound. The museum serves only the light part: an eye and a camera as one medieval scholar understood them. Ears, sound and the devices that use it are for your class to bring. 1
Curriculum expectations, with their official codes
- C2.8 identify sensory organs and devices that make use of the properties of light and sound
2 The lesson
What does your eye need in order to see?
The expectations ask you to name organs and devices that use light. Think of what must reach an organ or a device before it can form a picture, and what happens when that is missing.
Go deeper
Ibn al-Haytham set several candles before one hole into a dark place. On the wall inside appear as many spots of light as there are candles, each opposite its own candle. When one candle is covered, only its spot goes out 2. The record says this is why a camera's picture is sharp: the light from each point outside reaches its own point inside, along its own straight line 2. In his theory of seeing, the record says, the eye is affected by what arrives from the object 3.
Think about it
In the candle test, every candle gets its own spot because its light travels in a straight line through the hole. If the hole were much bigger, would each candle still get its own clear spot, and why or why not?
Into the museum
- Ibn al-Haytham's dark room: the candle test and the link the record draws to the camera.
- Ibn al-Haytham's account of vision: what must reach the eye for us to see.
- Ibn al-Haytham: the scholar behind both.
Try this
Read the account of vision and the dark room. Draw one diagram of light, an object and an eye, and another of light, an object and a hole in a wall.
3 Carry it further
Where this lesson leads in the museum.
4 Check yourself
Nothing here is marked or sent anywhere. It is for you.
In your own words: what does Ibn al-Haytham's integrated incoming-light theory of vision have to do with this lesson?
Compare with the card
An eye that receives. In his Book of Optics, Ibn al-Haytham joined the spreading of light and colour, the structure of the eye and the interpretation of what we see into a detailed account of vision. In it the eye does not reach out to touch an object with a ray; it is affected by what arrives from the object. The record adds that his model of the eye differs from the modern eye. What does your own eye need in order to see?
In your own words: what does Ibn al-Haytham's dark room (the camera obscura experiments) have to do with this lesson?
Compare with the card
From a dark room to a camera. TDV calls the dark-room experiment, which Ibn al-Haytham devised to prove that light travels in straight lines, the basis of today's photographic camera. Which device you know uses light to make a picture?
I can now