In a side-by-side comparison under optimal conditions, a holographic image is visually indistinguishable from the actual subject, if the hologram and the subject are lit just as they were at the time of recording. A microscopic level of detail throughout the recorded volume of my pdf displays with a different title virus can be reproduced. In common practice, however, major image quality compromises are made to eliminate the need for laser illumination when viewing the hologram, and sometimes, to the extent possible, also when making it. Holograms can now also be entirely computer-generated to show objects or scenes that never existed.
3D display technologies, which can produce superficially similar results but are based on conventional lens imaging. 1971 “for his invention and development of the holographic method”. They were not very efficient as the produced grating absorbed much of the incident light. Several types of holograms can be made. Transmission holograms, such as those produced by Leith and Upatnieks, are viewed by shining laser light through them and looking at the reconstructed image from the side of the hologram opposite the source. Rainbow holograms are commonly used for security and authentication, for example, on credit cards and product packaging. Denisyuk hologram, can also be viewed using a white-light illumination source on the same side of the hologram as the viewer and is the type of hologram normally seen in holographic displays.