British (native of Hungary) scientist Dennis Gabor

He made two-dimensional (flat image) holograms all the way back in 1947, before Star Trek offered us the Holodeck for inspiration! Further development was impossible during the next decade because light sources available at the time were not truly 'coherent'. Dennis Gabor won the Nobel Prize for physics in 1971. The coherence barrier was overcome in 1960 by Russian scientists N. Bassov and A. Prokhorov and American scientist Charles Townswith with the invention of the laser. Lasers have pure focused light that is ideal for making holograms. In 1989, members of the MIT Spatial Imaging Group created electro-holography, capable of producing realistic 3-D holographic images. In 2012 we saw the infamous Tupac hologram performance at Coachella. It was created by Digital Domain Media Group (who made CG images of Brad Pitt in 'The Curious Case of Benjamin Button') and was driven creatively by Dr. Dre, who performed alongside the hologram. However, this wasn't a hologram but rather it was a clever optical illusion technique known as 'Pepper's Ghost,' which dates back to a technique first described by an Italian scientist in the 16th century. That's a bit depressing, I thought we are a few years away from the Holodeck ... sadly not! So how far have we come with holograms? You can learn more about hologram concerts here. One area of research is very exciting, holograms you can actually touch, think about that! A team of researchers from The University of Tokyo have created the tactile hologram, which actually involves two basic pieces: A hologram, which is generated simply by shining an LCD projector onto a concave mirror, and a novel technique which creates ultrasonic waves so that the person interacting with it has the sensation of touch. Not many people realise that Hologram technology hasn't changed much since the birth of the idea. In fact, there is no such thing as a hologram that can be projected into thin air. Hmmm, that's not what we have been told right, well it's true. Holograms require the viewer to look through a piece of film. Holograms only create the illusion of a 3D object but that image is stored and only exists on a flat 2D surface just like a photograph. The recent excitement surrounding the Tupac (and others) 'holographic' concerts may indeed propel further research so that one day we may see mid air interactive holograms. Let's see!