Monocular Cues

Monocular cues are the set of depths we can perceive with just one eye.  One example of a monocular is linear convergence.  This is where a set of lines appears to converge at some point on the horizon.  A good example of this would be looking at a set of railroad tracks, although they do not converge it appears as if they do further on the tracks.

http://www.google.com/url?sa=i&rct=j&q=&esrc=s&frm=1&source=images&cd=&cad=rja&docid=5iG6TRmsZysj6M&tbnid=5JNiphzvZm_9tM:&ved=0CAUQjRw&url=http%3A%2F%2Fglobalcitizenblog.com%2Frailroad-tracks%2F&ei=WUh6UqqDCI7MsQSRnoHQCA&psig=AFQjCNGVbNwc3iYSl8W3B1qHEhC_22xEzA&ust=1383832002767924 

Another example of a monocular cue is occlusion.  When we see one object blocking another object, we assume it is closer in depth.  An example of this would be one box in front of another box.  In this case, we see the one box partially obstruct our view of the other box, therefore we determine that it is closer in distance.