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This paper examines the feasibility of producing multiplexed Bragg gratings for use as diffractive optical elements (DOEs) by coherent optical replication of a surface-relief phase grating into thick-film photosensitive materials. The use of such DOEs in light guide plates (LGPs) for optical imaging systems ensures energy-efficient light input into and output from LGPs and allows one to minimise their weight and size. We present simulation results for the interference structure fabrication process and recording of a series of multiplexed diffraction gratings in photosensitive materials.

The possibility of replication of high-frequency diffraction gratings obtained in a photoresist layer to glass substrates using polymer compositions (OKM and Technovit) is shown and their comparative analysis is carried out. The replication mechanism of the relief-phase structure is based on a two-stage process, which consists in obtaining a nickel master element, followed by applying a polymer composition to it and curing it under the influence of UV radiation. The replicating regimes were optimized (time, exposure, thickness of the polymer base), which made it possible to obtain relief phase diffraction gratings with a depth of surface relief comparable with the initial structure obtained in the photoresist layer. The diffraction efficiency of the resulting gratings was estimated, as well as the change in the depth of the surface relief of polymer copies obtained from one master element.

An augmented reality display based on a planar waveguide made in photo-thermo-refractive glass had been demonstrated. The monolithic integration of multiplexed volume Bragg gratings with the waveguide platform provided in/out-coupling and image transmission from a portable projector. Design and calculation of the grating configuration was performed. The optical replication method was simulated and implemented for manufacturing the multiplexed coupling elements. Resulted field of view was limited by the projection system of the prototype, however can be expanded beyond 50o.

An experimental study of the color reproduction quality of RGB color components, white and some “composite” colors in the developed augmented reality device based on two waveguides with diffraction elements was carried out. The color gamut of the device is determined. Color characteristics were analyzed by color coordinates in the xy system, presented on the chromatic diagram, and are given in the work.

The article describes the variants for using the relief phase diffraction gratings for a waveguide used as an optical input/output element for images in augmented reality systems. A characteristic feature of diffraction gratings with a surface relief, which, in this case, were recorded in the photoresist layer, is a relatively small relief depth (of the order of several tenths of a micrometer), while the diffraction efficiency of such gratings is quite high (up to 30%). The paper considers an implementation option for a waveguide with a common angular field of view close to 60°. The article presents the waveguide options used to output both monochrome images and display full-color images.

The present article is dedicated to the problem of computer-generated holograms application for measurement of optical wavefront curvature with high precision. A holographic wavefront sensor scheme based on a phase-only spatial light modulator, which is used for CGH displaying, is proposed. The presented optical scheme and processing algorithm are validated with numerical simulations and experimental modelling.

The work is devoted to the calculation of the optimal parameters of diffraction gratings for input and output of radiation from the holographic lightguides for augmented reality glasses. Two main stages can be distinguished, namely: the calculation of the grating’s period in each of the optical lightguides to obtain a multicolor image in a large field of view, and the calculation of the height of the relief profile (to maximize the diffraction efficiency).

A holographic wavefront sensor scheme using a phase-only spatial light modulator (SLM) with reduced cross-talk noise influence is proposed. A novel method for plane wave aberration measuring using a phase-only computer-generated hologram is devised. The proposed scheme and algorithm are validated with numerical simulations and experiments.

Hologram optical filters have been developed that make it possible to implement the wavefront decomposition for further analysis and calculation of aberrations. The implementationof hologram filters in both a photosensitive material and in digital form using phase spatial light modulators is considered. The obtained results can be used for the analysis of distorted wavefront in the problem of the laser beam control.

This paper analyses the possibility of obtaining a full color image using the holographic indicator based on a light guide plate with diffractive optical elements (DOEs). The parameters of the optical collimator system are calculated as well as the experimental results on generation of full color images are presented.

Objectives: This paper presents several variants of stable optical schemes of sight with Holographic Optical Element to solve a problem of changing direction of diffracted by it. Methods/Statistical Analysis: Optical scheme of holographic sight is presented where the transmission hologram together with mirror is working like the reflection one. Transmission hologram with mirror can be used to stabilize beam position for much bigger wavelength shift, than it is possible with reflection hologram. Findings: Results of calculations show that using of optical systems with a mutually inclined HOE and ADG allows reducing size of scheme with acceptable shift of image. Also it should be noted that the beneficial properties of reflection holograms can be realized using transmission holograms. Application/Improvements: Our results can be useful in devices with Holographic Optical Elements such as display systems and especially for development of holographic sight.

In this article analysis the possibility of using ion-plasma technology for etching the diffractive optical elements (DOE) directly in the glass, not in a layer of photosensitive material is described. Experimental samples on the light guide substrates for displays and signs-symbolic information indicators are obtained, as well as their basic parameters, such as the depth and shape of the surface topography and the diffraction efficiency are investigated. The experimental results showed the fundamental possibility of manufacturing the DOEs directly on the glass for the display of information systems.

Combined diffractive optical elements, which perform the functions of deflection, focusing or transformation of wave fronts and together with the spectral-angular selection of the incident polychromatic radiation, obtained on a single substrate, the method of their design and fabrication are described. The combination of four-level diffraction grating with plasmon meander diffraction grating as a spectral filter that have a bandwidth that varies with the angle of incidence are investigated for use in virtual displays and indicators.

A combination of computer-generated Fourier holograms (CGFH) and light guide substrate with diffractive optical elements (DOE) is described. The experimental results show that this combination can be used in display and sighting systems.

The holographic optical elements (HOE) for holographic indicators and methods of their production on the photosensitive materials are described. A distinctive feature of this optical scheme is the zone record of diffraction gratings and HOE, i.e., grating is divided into separate fragments that stitching at the recording process with a high-precision motion system of the plate.

A combination of diffractive optical elements for monochrome information virtual indicators is described. To reduce the spectral "blurring" of image in monochrome indicators with OLED-display or LCD-display with LED backlight the possibility of using the volume reflection hologram as a spectral filter is investigated. The theoretical and experimental results show that the volume reflection hologram can be used as part of a monochrome virtual indicator containing OLED-, LCOS- or LCD-display with LED-backlight and relief-phase gratings for output of radiation from substrate to reduce the spectral "blurring" of image.

A combination of holographic and diffractive optical elements (HOE-DOEs) for multicolor signs-symbolic information display system, screens and indicators is described. These elements combine the functions of high-efficiency four-level diffractive optical elements with spectral plasmon filters having a variable bandwidth dependent on the angle of incidence. The main parameters of such HOE-DOEs were determined using the Fourier modes method. The theoretical results show that a four-level diffraction grating and a plasmon filter can be combined based on their spectral-angular characteristics, opening up the possibility for their use in display systems.