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Introduction

Figure 1: Image sensor (touch or hover to zoom)

In a digital camera, the lens forms an image of the scene on a small electronic chip called the image sensor [1]. The sensor measures this light and converts it to a digital image. Figure 1 shows an image sensor like the one used in Bigshot.

The sensor works much like the retina inside the human eye [2]. On the retina, a dense grid of light-sensitive cells converts incoming light to electric signals. These signals are carried to the brain, where they are interpreted as images. Similarly, Bigshot's image sensor has a grid of detectors called picture elements, or pixels for short. Place the mouse over Figure 1 to see how an image sensor's pixels look under a microscope. When exposed to light, each pixel generates an electric charge that is proportional to the brightness of the light it receives. The charge is converted to a number and stored in memory. The numbers collected from all the pixels form a complete digital image.

Let's take a closer look at how an image sensor works.

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ReferenceReferences

[1] "Image Sensor," [Online]. Available: http://en.wikipedia.org/wiki/Image_sensor. [Accessed: Jun 4, 2012].
[1] "Retina," [Online]. Available: http://en.wikipedia.org/wiki/Retina. [Accessed: Jun 4, 2012].