APS
full spelling ： Active Pixel Sensor
An active pixel sensor is a type of image sensor. It is a second generation solid state sensor technology. APS usually refers to a CMOS image sensor, as opposed to a CCD image sensor. Active Pixel Sensor is emerging as an inexpensive alternative to CCDs.
Active Pixel Sensor was invented and developed at JPL (NASA Jet Propulsion Laboratory). APS technology utilizes active transistors in each pixel to buffer the photo signal. Such an image sensor is produced by a CMOS process. The APS technology has been successfully transferred to several commercial companies. The uses of CMOS APS technology in commercial applications include biomedical imaging, web cams, multimedia machine vision, high speed imaging and low cost video phones.