Real 3D images can now be displayed in mid-air:
Many previous displays in 3D have been virtual images on 2D planes which, due to human binocular disparity, appear as 3D. However, the limitation of our visual field and the physical discomfort caused by wrongly identifying virtual images makes these displays less than perfect.
The new device uses the plasma emission phenomenon near the focal point of focused laser light. By controlling the position of the focal point in the direction of the x-, y-, and z-axes, real 3D-images in air (3D-space) can be displayed.
This should be very useful for studying 3D shapes the easy way. It's also useful for studying starmaps in StarWars-style. ;)