The Reinvention of Holography

The Beginnings Of Holography

The images that light can form represent important ways to convey information to our consciousness. The two-dimensional (2-D) image has until recently been the main way of recording the kind of information human vision gives us. For most of the nineteenth century and the first quarter of the twentieth, before the invention of television, still photography and, later, motion pictures were the only method of producing images that truly represented the visual appearance of the world. The development of integrated semiconductor circuits in the middle of the twentieth century heralded the introduction of computer science, and with the advent of the laser, optical fibres and the Internet, it could now be asserted that the existence of our present-day society depends almost entirely on the successful application of information technology. One of its most important applications is the transfer of 2-D imagery via the modulation of 1-D electronic signals to illustrate the 3-D nature of the world we are living in – even 4-D, if we include the dimension of time. To our conscious perception Nature herself appears in three dimensions and in real time. But the 2-D information that is still standard for conveying visual information can show us only a single perspective in an image, restricting our perception of the 3-D world we live in. For many years people have asked whether it might be possible to record – and recover – the total; information present in a 3-D image.