**5.5 Main special features of samples of volume polymer medium**

Material Difphen belongs to the group of polymeric recording materials, implementing the diffusion enhancement principle, which is at present fruitfully used by various authors in a number of science and engineering projects. Material samples have certain holographic, and physical and mechanical parameters, determined by the devised modes of sample synthesis and of hologram construction. The following main special features can be noted.


Light-Sensitive Media-Composites for

Advantages of the technique are:

Drawbacks of the technique are also obvious: • labor intensity of data processing;

Recording Volume Holograms Based on Porous Glass and Polymer 67

• acquisition of information, using both diffracted and zero beams, and formation of optical scheme of an experiment to achieve necessary measurement accuracy; • possibility to trace the dynamics of contour variation for the hologram under study

• recording of selectivity contour takes place in a single measurement act;

both in rapid processes and in sufficiently slowly varying conditions.

• necessity to stabilize and fine adjust the scheme elements for experiments.

Fig. 12. a - effect of halfwidth of spatial spectrum of reading radiation (Δψ) on ratio Δθexp/Δθtr at different values of Δθtr: 1 – Δθtr = 0.5 mrad; 2 – Δθtr = 1 mrad; Δθtr = 3 mrad. Δθexp is the halfwidth of experimentally measured contour;Δθtr is the halfwidth of true contour of the hologram under study. b,c,d - schematic diagram of measurement of angular selectivity contour by collimated (b) and divergent (c) beams of monochromatic radiation; measurement of spectral selectivity contour by collimated radiation beam with a wide wavelength spectrum (d): 1 – radiation source, 2 – optical system for formation of divergent radiation beam; 3 – spectral instrument for expansion of wavelength spectrum in spatial

frequencies; H – hologram; RD – radiation detector.

5. Feasibility of producing samples of thickness from tens of microns to several millimeters.
