Designing of diffractive optical elements (DOEs) requires knowledge about possible methods of calculating and simulating their performance, possible materials and characteristics of the particular range of radiation. The demand for compact and lightweight setups intuitively leads to the application of diffractive elements, which are characterised by both these features, having though one significant drawback – large chromatic aberration. As DOEs are meant to introduce specific phase shift, they are related to one particular design wavelength (DWL). However, thanks to different design approaches (e.g. kinoforms of higher order), elements functioning also for broader spectral ranges can be created. They are thicker, thus usage of appropriate material, having small attenuation coefficient or adjusting structure height during design process is required. Here, a simple method of designing diffractive lenses working in on- and off-axis regimes is presented. Using 3D printing for manufacturing is possible because different materials, polyamide, wax or chocolate, are relatively transparent below 0.5 THz. Each material has its own limitations like hardness, thermal resistance or ability for mechanical processing that have to be considered. Thus, using such simple methods of manufacturing for DOEs working for frequencies larger than 0.5 THz can be achieved using different design approach and ordinary devices with easily accessible materials (e.g. paraffin). It seems very important to create a method of producing diffractive elements that will be available in many laboratories to show the advantage of using such optical structures.
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