The complexity of the fabrication process has made holograms impractical for everyday visualization tasks, but this may be about to change.

Sunny Bains

Associate Editor, Technology

Scanned, filtered by optical character recognition and adapted from LASER FOCUS WORLD APRIL 1993 159. For further details please see the original article.

Display holography has often been a victim of its own hype. People tend to confuse science-fiction movie "holograms" and Disneyland mirror tricks with the real thing, and then they go to holographers with unrealistic expectations. Rather than shy away from them, holographers have taken on some of these misconceptions as challenges. A holographic printer, which would provide three-dimensional (3-D) hard copy of medical, architectural, or other computer-aided-design databases, is one challenge that is close to being met.

In one sense, it is true that making a hologram is very easy. With a homemade isolation table, any kind of single-mode continuous-wave visible laser, a lens, and an appropriate holographic plate, you can get a result. However, restrictions on the object of this hologram pose a problem. It has to be small (assuming laser power is low), reasonably-but not too-reflective, very stable, and quite dead. If you have money, you can scale up to a pulsed setup (see "Pulsed Nd:YAG lasers bring versatility to display" on p. 161), which allows you to image living things. But you still have to get into your lab whatever creatures you want to image, and they have to be real physical objects.

A physical object is needed because it is being imaged directly. The 100-perspective views for the two-step stereogram of an Acura NSX (right) were generated on a Silicon Graphics Inc. (Mountain View, CA) workstation using software from Alias Research (Toronto, Ont., Canada).