Image sensor of Digital Camera those are in consumer level usage can be CMOS or CCD. There are some differences inthe technology and performance of Image sensor.
An image sensor is a device for recording of two-dimensional images in visible light range. There are also two-dimensional semiconductor detectors for recording high-energy ionizing radiations such as X-ray and gamma radiation. Technological solutions to capture an image in the visible range to the infrared are often based on two-dimensional arrays (“array”), whose signals are read electronically. Especially when this is known as infrared focal plane array (FPA).
Usage of Image sensor
In digital photography the Image sensor is the equivalent of conventional photographic film. The sensor is an array of photosensitive elements that works by converting light into electrical signals that captures that can be stored, measured and converted into an electronic representation of the pattern of light reaching the Image sensor.
Components of Image sensor
Each unit of the photosensitive elements of the Image sensor is called a pixel (picture element). The number of pixels on the Image sensor is usually measured in megapixels.
Another important factor of Image sensor is the size and shape. A large sensor containing a relatively small number of pixels should have a large area per pixel, and vice versa: a small Image sensor with the same number of pixels will have a reduced area per pixel.
Types of Image sensor
Examples of image sensors used in visible and near infrared photography :
Silicon image sensors have relatively low image noise. CCD image sensors, with a color sensitive sensors (single filter per pixel) are used for color images. CCD means Charged Couple Device.
Both CCD and CMOS as image sensor has some negative points and none of these are perfect when compared to a physical traditional film.