Image sensors are silicon chips that capture and read light.
They can perform camera functions on-chip. Charge-coupled devices were the prevailing technology in image capture for 30 years. By the late 1990s, they began to be replaced in key applications by CMOS image sensors. Advantages of CMOS Image Sensors Over CCDs CMOS image sensors draw much less power than CCDs. This allows the finished digital camera system to run longer on batteries a major advantage in hand-held products.