How Digital camera works

A digital camera works in the same manner as a conventional camera as far as optics are concerned, with one main difference – conventional camera use film to sense and store the image while digital cameras sense the image on a CMOS or CCD element, which is a light-sensitive element that consists of millions of pixels. The CCD is an array of very tiny photo transistors that are arranged in a grid. When this grid is exposed to light, it generates electricity depending upon the intensity of light falling on it. These transistors are the smallest elements on the sensing device and they from the pixels in the image. Therefore, the greater the number of pixels on the CCD, greater will be the resolution supported and consequentially, greater is the clarity. On a monochrome digital camera, one pixel would be made up of a single transistor but in color digital camera, each pixel would be composed of three separate transistors, red, green and blue. Together these three colors can represent any number of colors depending upon the light falling on them. These transistors generate continuous electrical signals that are sent to an Analog to Digital Converter (ADC) where these signals are converted to a digital format. This is then sent to a specialized processor called a DSP (Digital Signal Processor) that programmed specifically for handling image information, where setting such as white balance, filters and image compression is performed. Finally, the image is sent to storage memory. Another very integral part of most digital cameras is the LCD screen that lets the user view the setting the camera is using, edit, organize and preview pictures as well as access and change the mode of its operation. These digital images can now be viewed on an external display device such as a monitor or a television and can be down loaded to the computer using the TWAIN driver provided by the manufacturer