The following picture shows the latest 2D vision sensor, called Pixy2/CMUcam5 (https://pixycam.com/pixy-cmucam5/), which is able to detect color objects with high speed and accuracy, and can be interfaced with an Arduino board. Pixy can be used for fast object detection, and the user can teach it which object it needs to track. The Pixy module has a CMOS sensor and NXP LPC4330 (http://www.nxp.com/) based on Arm Cortex M4/M0 cores for picture processing. The following image shows the Pixy/CMUcam5:

The most commonly available 2D vision sensors are webcams. They contain a CMOS sensor and USB interface, but they do not have any inbuilt vision-processing capabilities like Pixy has.