How do cameras work?

How do digital cameras grab a picture?


Kidizoom-CameraDigital cameras are everywhere nowadays. In phones, in tablets and in computers.

But how do they actually work?

Well, light goes into the lens and lands on a small sensor.  The sensor is divided into millions of tiny squares – or pixels as they’re called.

Each little square is a bit like a solar panel.  You know that a solar panel takes light and makes it into electricity?  Well the same thing is going on in your camera.  As the image hits the sensor, each square gets a different electrical charge depending on the brightness and colour of the light hitting it.

The computer in the camera takes the grid of electrical charges and converts them into a picture.  It’s recorded as a computer file so it can be accessed as many times as you like and moved around.

Different cameras have different amounts of squares.  ‘Mega’ means million, so a two megapixel camera has two million pixels – or squares, on its sensor.

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