We present an overview of the development of holography, from Gabor to the present. We describe some of the peculiar and interesting twists in this long development. We look at some of the successes and failures, and at some of the early predictions, including those that came to pass, and those that went awry.

We consider the method of reference-free selectograms that allows obtaining 3-D holographic images of objects illuminated by natural light. The method of reference-free selectograms is based on the phenomenon that is relative to the phenomenon being the base for Lippmann color photography. In this connection, the reference-free selectogram method, the Lippmann color photography method, the method of 3-D reflection holograms, and the local reference beam generated hologram method are analyzed and compared. Like the Lippmann color photograph, the reference-free selectogram represents the recording of a picture of standing waves resulting from the interference of the object wave with its “twin”—the wave that is split off from the object wave with the help of an optical element. The methods differ in the direction of the propagation of the twin wave. In the Lippmann color photograph, this wave is formed by means of a mirror and propagates in the direction opposite to the object wave. For the reference-free selectogram case, the twin wave is formed with the help of a diffraction grating and is directed in the same way with the object wave direction. We show that both in the Lippmann photography and in the reference-free selectogram the main information on the angular distribution of the intensity of the radiation recorded is contained in a thin layer that fits snugly to the surface of the optical element. The thickness of this layer is of the order of several microns. However, the information on the fine details of an object is spread in depth by the order of several millimeters.

Replication technologies such as embossing, molding and casting are highly attractive for the fabrication of surface relief hologram and diffractive optical element (DOE) microstructures. They have very high resolution, typically in the nanometer range, and allow the fabrication of a large area, complex microstructure by low cost, high volume industrial production processes. Their use is already well established for gratings, white light holograms, and diffractive foil with typical relief structure shallower than 1 μm and the extension to the fabrication of deeper and higher aspect ratio microstructure is underway. The combination of replication technology with other processes such as dry etching and thin film coating can also offer new possibilities in the design of DOEs suitable for mass production. Replication is expected to become a key technology for the microfabrication of a wide range of DOEs in the future. We review the major hologram and DOE replication techniques and describe recent work and results.

The results of the theoretical and experimental study of the dispersion characteristics of thick reflection holographic grating are presented. The analysis of the diffracted beam intensity is made for the conditions when both the wavelength and angle of the reconstructing wave differ considerably from those used at the recording. The magnitude of the diffracted signal can be described through the joint function of the angular-spectrum selectivity. This is of special interest when the color holographic image is reconstructed with a spectrally wideband light source. In this case the character of the angular-spectrum selectivity function should be taken into consideration for true color holographic image reconstruction.

Photosensitive polymers are becoming increasingly important for holographic applications. Commercially available polymers have proved essential to the development of holography as a tool to prevent counterfeiting, for holographic optical elements, as media for display holography, as well as media for waveguiding and to make optical interconnects. Simple polymers such as PVA, PAA, PVCz and PMMA were shown to be quite useful in the field of polarization holography, real-time holography, and non-linear optics. High real-time diffraction efficiency as achieved with dye doped dichormated polyvinyl alcohol (DCPVA) and polyacrylic acid (DCPAA) opens the door to a more extensive usage of these polymers for specific applications. However, development procedures and fabrication techniques have to be established to permit broad utilization of these simple and inexpensive recording media.

The choice of a phase recording material strongly affects the utility of the final recording. For display holograms properties such as brightness, contrast, color range and color saturation might dominate and the choices are part art and part science. For holographic optical elements (HOEs), the extended range of properties that may require manipulation and the choices of materials to obtain each property in the required quantity makes a working knowledge of what can be done extremely useful. We present the fundamental properties of phase recordings and the fundamental properties of many phase materials so that a choice that will get you from plan to product can be more readily made. Recipes are not given but references to recipes are and modifications or procedures that can modify a well-known material may be described. The object is to make the reader aware of both the strong functions of these materials and the weak or subtle properties so that a design may be reviewed for feasibility a little more thoroughly, and hopefully the route to a functioning product will be shorter and less costly.

It is well known that transmissive and reflective type volume holograms have very high angular and spectral selectivity. Such highly selective holograms can find wide application in different fields, namely, three-dimensional imaging, diffraction optical elements, holographic storage, etc. The main problem in manufacturing thick holograms (of about a millimeter thickness) is in developing very thick photosensitive media, in which a grating can be recorded by illumination with an interference pattern. The analysis shows how different kinds of inhomogeneities and material shrinkage cause distortions in the reconstructed image and hologram selectivity properties. A review of the Russian materials (confirmed by experimental data) suitable for the recording of volume holograms is made.