The subject matter of this report is the development and test of a technology for the industrial manufacturing of large format holographic optical elements (HOEs) for technical applications that facilitates the choice of an operating wavelength between UV and IR and the selection of a desired bandwidth that may vary between tens and hundreds of nanometers. Such requirements are essential for the fabrication of spectrally selective holographic lenses and mirrors for use in photovoltaics and solar chemistry. Large format HOEs are also finding increased application as facade elements in the control of radiant energy in buildings. Data is presented illustrating the methods used to control the shift of the operating wavelength and to adjust the bandwidth of the HOE. These methods are based on the understanding of the structure and properties of the DCG holographic material. For example, the recording of holograms for the blue part of the spectrum requires the use of a filler material to swell the hologram and a specific development process to shrink it subsequently to the desired thickness of the layer. Thus, the required filler material should have the same optical properties as the DCG and should be water soluble. The material should be optically neutral and play no more than a passive role as padding in the hologram fabrication process. A similar technique, based on the permanent swelling of the hologram, is used to shift the operating wavelength of a reflective hologram into the IR and to modify its bandwidth.
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