There is unfortunately still a long way to go in cost reduction. The 360 degree LIDAR (Velodyne) that Google uses (the rotating thing on the top of the car) is

There is unfortunately still a long way to go in cost reduction. The 360 degree LIDAR (Velodyne) that Google uses (the rotating thing on the top of the car) is the most essential sensor, but costs about $80000. Other autonomous cars also use quite expensive technology like laser scanners and so on. Unfortunately it is not as simple as only IR sensors :)