based on microsoft kinect developer [13], the depth sensor has two depth ranges: the default range and the near range(shown in the depth range enumeration).
In figure 2 illustrates that the sensor depth ranges in meters.
the default range is available in both the kinect for windows sensor and the kinect for xbox 360 sensor; whereas the near range is only available in the kinect for windows sensor which shown in figure 2.
as such, the depth sensor can be seen as a device that returns(x,y,z)- coordinates of 3D objects.
From figure 1,default range has ablind spot from 0m to 0.8m,where in cannot generate raw depth data for anything in that region .
It also generate raw depth data for anything after 4 meters.
On the other hand,the near range has a blind spot from 0m to 0.4m where it cannot generate any raw depth data for anything in that region
it also acnnot generate any raw depth data for anything after meters