The Technology Behind Digital Cameras

Technology has revolutionized the concept of capturing live images. The earlier concept of producing permanent photograph was based on pure chemistry. In 1830, Louis Daguerre, devised the first practical way of producing permanent photographs. Today we are talking about the computerized photo imagery in the filmless picture taken by a device that is smart in electronic intelligence and in appearance - digital camera.

A digital camera takes video, still photographs, or both digitally. It records images on a light sensitive sensor. Instead of using a film, an arrangement of charged-coupled devices-light sensitive semiconductors, which stores electrical charges,-does the job. These digital sensors-composed of pixels -transform the light from the scene snapped into an analog signal which is then converted into a digital version. One electronic filtering system regulates color and other picture components. Another system reduces the picture. The image is finally sent to a temporary storage area and ultimately onto a memory card. Many compact digital cameras can record sound, video and still photographs.

The images are transferred to a computer where they can be modified, printed, attached to email, inserted in web pages, etc. The most significant advantages of a digital camera are its memory capacity and ability to screen the images taken on a tiny video monitor.

The technology of the digital camera relates to the same technology of Video Tape Recorder. The first VTR in 1951 captured images from the television by converting the information into electrical impulses (digital) and subsequently saving them onto magnetic tape. It was in 1960s when NASA had made a major breakthrough by converting analog to digital signals by means of the space probe for mapping the surface of the moon. Also digital imaging had its other uses in spy satellites.

Kodak scientists invented the first mega pixel sensor capable of recording 1.4 million pixels. In 1991, Kodak released the first digital camera system- a Nikon F-3 camera equipped with 1.3 megapixels aimed at journalists. The first digital camera for the consumers which worked with a home PC via a serial cable were the Apple Quick Take 100 camera(1994), the Kodak DC40 camera(1995), the Casio QV-11 with LCD monitor(late 1995) and Sony`s Cyber-Shot Digital Still Camera(1996).

The main features of a digital camera can be summarized as follows:

Resolution: Resolution means sharpness of a picture. The higher the number of pixels, the higher is the resolution.

Memory: The pictures are stored like a data file in a digital camera. The size of the memory determines the number of picture which can be taken, stored and downloaded in the computer.

Flash Type: Most digital cameras have a built in flash of a range around 10 -16 feet which is required to provide extra light needed to take photographs in insufficient light.

Optical Zoom: Normally two types of zoom lenses are used viz., digital and optical. The optical zoom lenses serve more purpose like adding detail and sharpness.

Compression: This process helps to reduce the file size.

Lens: The length of a lens determines how much of a scene will fit into a picture.

LCD Screen: A very interesting feature of a digital camera is the LCD screen which permits one to see what the photo will look like before and after taking photographs, leaving room to decide whether to erase or save the photo.

In the market there are several brands of digital camera which are selling successfully and the continuous improvement in Technology is leading way to introduction of more and more exciting features in the digital camera.