A sight for sore eyes IBN AL-HAYTHAM DISCOVERED THE PRINCIPLE BEHIND THE CAMERA BEFORE IT
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top to bottom and place it inside the container. The tube should be as wide as
HAD EVEN BEEN INVENTED. I GUESS IT JUST CLICKED FOR HIM, HA HA!
the container. 3
BRAINY BREAKTHROUGH NAME: IBN AL-HAYTHAM (AD 965–1038)
Stretch a piece of greaseproof paper over the open end of the container and secure it with an elastic band.
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NATIONALITY: BORN IN MODERN IRAQ
Roll the other sheets of black paper into a tube and secure it with sticky tape. Then stick this black tube to the greaseproof paper end of the container.
5 Ibn al-Haytham was the first person to suggest you see something when light
Take the lid off the container. Make a tube by rolling a sheet of black paper from
So there it is – you’ve made a pinhole viewer – I hope the Sun is still shining! Peep the viewer out through the curtains and look through the black paper tube end.
reflects from that object into your eye. Before then many people thought that DON’T LOOK AT THE SUN OR YOU’LL NEED NEW EYEBALLS!
the eyes produced a ray to see things by. Ibn al-Haytham used maths and experiments to show that light travels in straight lines and it bends (refracts, as scientists say) as it passes through water. Here’s a device that he built to help with his research…
WHAT HAPPENS:
You should see an upside-down, back-to-front view of the outside world.
WHAT YOU NEED:
THIS IS BECAUSE:
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Sticky tape and scissors
You’re looking at light that shone through the hole and is being projected on the
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4 sheets of black A4 paper – ideally non-shiny
greaseproof paper. As Ibn al-Haytham realized, light travels in straight lines, and that
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Container about 20–23 cm long – one of those crisp tubes is ideal
means light from the sky is projected on the bottom of the paper and light from the
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2 large elastic bands
lower part of the scene makes it to the top of the paper, so you see the world upside
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Drawing pin, small screwdriver, hammer and nail
down. Left and right are reversed in the same way. This is much the same way as a
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Greaseproof paper
camera works, although there is a film or a light sensor rather than paper at the back
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Pet adult
of the box.
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Bright sunny day
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Room with thick, dark curtains
Horrible Science: Famously Foul Experiments by Nick Arnold
WHAT YOU DO:
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Use the drawing pin to make a hole in the middle of the bottom of the container. Use the hammer and nail and then the screwdriver to make the hole a little larger. The ideal size is 4–5 mm – don’t make it bigger. Younger readers should order their pet adult to undertake this tricky task.
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