Comparison between 2-D and 3-D hologram properties is made. Light-sensitive materials used for recording holograms of several millimeters in depth are considered, including the polymer light-sensitive material Reoksan, whose action is based on the sensitized reaction of photooxidation, and light-sensitive materials obtained by introducing a light-sensitive compound into porous glass. The results from the studies on the creation of optical elements, based on deep 3-D holograms - a supernarrow spectral selector with a transmission band width of 1 A, and an element for expanding the image in an orthogonal Walsh function system - are given. The properties of deep holograms of Walsh function light models are considered in detail. It is shown that each of these light models reconstructs the object corresponding to it independently of one another, which allows to use these models as a reference source in the multiple hologram recording.