Are they? Visual acuity at the fovea is around 1 arc minute. Translating that to 150 by 100 degrees of visual field (humans have a larger visual field) gives a resolution of 9000 by 6000 pixels.

Of course, the human eye doesn't work that way: resolution drops off rapidly away from the fovea. Many electronic sensors do work that way, though. So, individual sensors may, for some tasks, be inferior to human 20/20 vision.

I googled to find out whether the sensors on Google's driverless cars had anisotropic sensors (a simple solution would be to have a wide-field and a telephoto camera), but cannot find good info. Anybody know more?