# Chalcogenide Thin Films--Holographic Media for Augmented Reality Devices
## 5 Conclusions  
Within this work, chalcogenide films study was carried out both analytically and experimentally. Modeling allowed estimating the desired optical properties of ChGs to use them for HOEs/DOEs recording for AR-systems. Common and optimized compositions of ChGs films were synthesized, studied, and used for experimental investigation of volume and surface relief holographic gratings recording. The study showed that the FOV provided by the ChGs-based waveguides can reach the values of \(>\)50 deg with proper substrate refractive index. It was also possible to reach high transparency in blue wavelength range by optimizing the ChG composition, while diffraction efficiency could be increased by means of relief recording. Thus, we consider that the proposed holographic materials are potentially suitable for AR applications. However, the HOE recording in ChGs was extremely inefficient and unprofitable. Diffraction efficiencies reached only about 1% or less. The relief recording should have enormous exposure doses to obtain acceptable diffraction efficiency (several kJs). Moreover, the recording wavelength should be very carefully adjusted for each composition in order to be exactly at the edge of the composition absorption band. Such challenges reveal that the present study could be considered as the basis for the future research and development, which are needed before ChGs-based HOE waveguides can reach sufficient quality and efficiency. Conceptualization, V.N.B. and N.V.M. ; methodology, V.N.B. ; investigation, V.N.B., R.A.O., E.S.M., S.A.I., D.Y.T. and P.I.L. ; software, G.N.V. ; resources, S.A.K. ; writing--original draft preparation, V.N.B., R.A.O. and S.A.I. ; writing--review and editing, A.E.A., V.N.B. and P.I.L. ; supervision, N.V.M. ; project administration, M.V.P. All authors have read and agreed to the published version of the manuscript. This research received no external funding. Not applicable. E.S.M and S.A.I. thank for the supporting by ITMO-2030 Development Program. The authors declare no conflict of interest. * _[PERSON] et al. (2018)_ [PERSON]; [PERSON] [PERSON]; [PERSON] [PERSON]; [PERSON] [PERSON]; [PERSON] [PERSON]; [PERSON]; [PERSON] Field of view: Not just a number. _Proc. SPIE_**2018**, _10676_, 1067604. * _[PERSON] et al. (2020)_ [PERSON] [PERSON]; [PERSON]; [PERSON]; [PERSON] [PERSON]; [PERSON] Holographic waveguide periscopes in augmented reality displays. _Opt. Spectrosc._**2020**, _128_, 1828-1836. [CrossRef]
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