Two viewpoints allows distance to be calculated, similar to the way that binocular vision gives us depth perception.
两个视点将可以算出距离，就像双眼视觉给与我们深度的感官。
2
For binocular visual function, 2.1% had a disturbance in binocular simultaneous perception, 4.3% had defective binocular fusion, and 16.7% had a qualitative stereopsis loss.