Digital Single-Lens Reflex Camera

Cameras serve to record and preserve the scenes that are viewed through their lenses. The origin of modern cameras dates back to the 4th century BC when the Camera Obscura was invented. Later, the invention of silver halide film cameras meant that images could finally be recorded on film.

Nowadays, digital cameras provide the same function by recording images as digital information. The basic working principle of a digital camera and its image capturing are lenses focusing the light rays coming from the object and making them into a coherent image. Diaphragm determines amount of light to be entered and shutter speed determines time of exposure. When light falls onto a sensor (CCD), a corresponding electric charge is created. An ADC converter is then used for converting electric charge to a digital signal in binary form. Each of the charges stored in the photosites has a binary value assigned, storing them as pixels. A pixel is a point sample of an image which contains three basic color components. Pixel per square inches indicates the size and quality of the image. Construction and mode of function of a digital camera varies from type to type but the basic principle of taking an image is always the same.