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Holographic characteristics of chalcogenide film materials with a typical thickness of 0.5–1.5 µm of a number of Ge-S and As-S compositions have been studied theoretically and experimentally with the aim of using them in augmented reality waveguide devices. The possibility of controlling the spectral and holographic properties of materials by varying their composition is shown. The recording of both volume and surface holographic elements operating in the total internal reflection mode was carried out. The operation of holograms in the “periscope mode” with a diffraction efficiency of about 10% is demonstrated. It is concluded that the recording of high-performance holographic elements on chalcogenide films requires significant values of exposure energy when recording in the near UV range (325–355 nm), which makes holographic recording currently ineffective for creating such elements.

To date, planar waveguides are under development for augmented reality systems with waveguide combiners. The next step of their development is the transition to curved waveguides, which could make the combiners more ergonomic. In the present work, a method has been developed that makes it possible to minimize aberrations of a virtual image during its in-coupling to and out-coupling from a cylindrical waveguide. The method is based on the use of in-coupling and out-coupling diffractive optical elements (DOE) with a variable grating period, which provide virtual image pre-aberration when radiation is in-coupled into the waveguide and compensation of the waveguide curvature at the out-coupling. Analytical laws are derived for the period variation of the in-coupling and out-coupling DOEs for an arbitrary curvature of a cylindrical waveguide. These dependences were optimized to minimize virtual image aberrations when using a radiation source with finite dimensions. Samples of cylindrical concentric PMMA waveguides with a curvature radius of 150 mm and in-coupling/out-coupling holographic optical elements (HOEs) have been created. The transmission of test monochrome virtual images through these waveguides without doubling and breaks in the field of view has been experimentally demonstrated.

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Currently, Mid-Air Display (MAD) technology is of a great interest to practitioners. Potential application in consumer products with large aperture “floating” image displays, like TV, monitor, ATM, vending machine, home appliance, etc., and contactless user interface for remote control increase their attractiveness. In order to obtain enlarged mid-air image size at maintaining large horizontal Field of View (FoV) and high light display efficiency, the following challenges are to be solved: developing high fill-factor Diffractive Optical Elements (DOE) architecture with optimal size of out-coupling aperture and designing custom-made projection optics with specified exit pupil matched to in-coupling DOE. As a possible solution to abovementioned problems, the authors propose a MAD based on commercially available projector source, custom-made projection optics and designed corner DOE waveguide architecture with focusing Fresnel lens. The mid-air image is formed at the back focal plane of the Fresnel lens, between the viewer and the display. For mid-air image with five-inch diagonal and 32° horizontal FoV, we take waveguide out-coupling aperture of 245 x 145 mm2 and Fresnel lens with back focal length of 220 mm and obtain image brightness ~1000 cd/m2 due to custom projection optics. Basic contactless user interaction was also implemented.