CCD Camera and its Working| Charged Couple Devices (CCD)

 Charged Couple Devices (CCD)

CCD is abbreviated as charged couple devices. It enables a direct connection between an object, a photon, and an image.

Composition

It consists of small pixels which are impregnated into silicon wafers. Each pixel is connected to a capacitor that stores charge. It expresses the electrical charge into a digital value. A Camera has three main devices:

§     Body

§  CCD chips

§  Electronics

 

Body:

It is the mechanical part of the camera. It saves the CCD chip from UV rays. It may be made up of plastic or any other substance which protects the inner materials.

CCD chip:

Pixels are made up of metals. When light fall on pixels; the electron becomes excited. The pixel store electrons, show voltage on a voltmeter, and stores electron in a capacitor attached to the pixel.

Electronics:

It deals with the conversion of electric charge into an image. The charge stored in Capacitor depends upon the intensity of the photon. The intensity of charge is directly proportional to the image clearance. As the intensity of charge is increased the image becomes more clear and best.

Working of CCD

CCD works in three different phases which are given below;

§  Clearing phase

§  Interpreting phase

§  Read out phase

Clearing phase:

When light fall on a pixel and charge is stored by a capacitor, the charge moves downwards up to a clearing line. The charge on the clearing line moves parallel and emits fairly.

Interpreting phase:

CCD becomes empty now and carries zero charges. The charge is developed again by the stored capacitor.

Read-out phase:

All the movement of the capacitor occurs in milliseconds. The image is stored in cameras and saved.