Cam broadcasts for adults
CCDs and CMOS chips, the two kinds of image sensor, do this job in slightly different ways.
Both initially convert incoming light rays into electricity, much like photoelectric cells (used in things like "magic eye" intruder alarms or restroom washbasins that switch on automatically when you put your hands under the faucet).
So it's essentially a digital device where a CCD is an analog one.
CMOS chips work faster and are cheaper to make in high volume than CCDs, so they're now used in most low-cost cellphone cameras and webcams.
Unlike a digital camera, a webcam has no built-in memory chip or flash memory card: it doesn't need to "remember" pictures because it's designed to capture and transmit them immediately to a computer.
Other popular cams are made by Logitech, Creative, Hue, and Teck Net.
The lens screws in and out to increase its focal length, controlling the focus of your cam: Now take the lens off and you can see the image sensor (CCD or CMOS chip): it's the square thing in the middle of this circuit.
Only the tiny, green-colored central part is light-sensitive: the rest of the chip is concerned with connecting the light detector to the bigger circuit that surrounds it: Here's a closeup: So the image sensor is the "electronic eye" of a webcam or a digital camera.
Just like a digital camera, it captures light through a small lens at the front using a tiny grid of microscopic light-detectors built into an image-sensing microchip (either a charge-coupled device (CCD) or, more likely these days, a CMOS image sensor).
As we'll see in a moment, the image sensor and its circuitry converts the picture in front of the camera into digital format—a string of zeros and ones that a computer knows how to handle.Let's just refer to "the image sensor" from now on (and forget about whether it's a CCD and other chips or a CMOS sensor).