Charged Coupled Device

A charge-coupled device (CCD) refers to a device that consists of a series of linked light-sensitive capacitors that take in an image through the transfer of electrical charges. Invented in 1969 By Willard Boyle and George Smith, charge-coupled devices are commonly used today in digital photography, especially in astronomy or high-speed photography.

By transferring a photoelectric effect into a charge, the charge-coupled device can effectively create electronic images. While traditional photographic film can only pick up two percent of incident light, CCDs can pick up seventy percent of it, making them far more effective than film.

After a charge-coupled device takes in and transfers each slice of a given image, the last capacitor of the series converts the series of charges into a given voltage that is then stored in a digital camera’s (or a telescope’s) memory. At this point, the voltage can be downloaded to a computer, printed on a digital printer or stored in an online photo album.

In scientific arenas, CCDs in telescopes can track the movement of the stars and other celestial entities.

One new alternative to the charge-coupled device is the active pixel sensor (APS). The APS is cheaper, smaller version of the CCD.