Multilayer photonic-integrated circuit design for dense random waveguide distribution addressing, application to near-eye display

Abstract

Near-eye displays have become a technology of high interest for Augmented, Virtual and Mixed reality due to the unique immersive experience they provide to the user. The majority of these devices use macroscopic optical elements that make them bulky and heavy. Our team has proposed a disruptive near-eye display concept that uses the self-focusing effect to project an image to the user's retina. To form an image, emissive points are generated from a dense photonic integrated circuit embedded within the lens of a pair of smart glasses. In this work, we present the design of a dense routing architecture that addresses thousands of randomly distributed emissive points from a few hundred inputs. The circuit combines unbalanced waveguide splitter trees with a non-periodical addressing onto a dense waveguide network. We present the design optimization through numerical simulations and estimate the overall device performance based on simulation results. A waveguide interlayer crossing simulation indicates losses better than 0.003 dB/crossing, which guarantees low optical losses over thousands of crossings. By unbalancing correctly the splitter trees, we can obtain homogeneous power profiles over an emissive point distribution. The experimental validation of our design will be a major step towards the elaboration of a first prototype.

Convergence of mathematical and physical optical designs for the development of random photonic integrated circuits for an unconventional AR display concept

“…made of 3-dB splitters). Such an estimation, based on simulation results, is present in another of our work 14 . In this paper, we only present the calculation to optimize our splitter tree.…”

Impact of emissive point distribution density in a retinal projection near-eye display

“…The self-focusing effect requires all the emissive points (EPs) of the EPD to originate from a single coherent source. To that end, we base our concept on the use of a photonic integrated circuit to bring light to specific locations from a laser source [10]. The intersection of the waveguides with electrodes provides a way to extract light from the device [11,12].…”

Directional display for AR applications based on holography and photonic integrated circuits

“…These µ-displays do not allow for control over the emission properties, resulting in low power efficiency in the AR system, or a limited EyeBox (EB) and Field of View (FoV). This paper introduces an innovative display concept that uses photonic integrated circuits (PICs) in the visible range [8], [9], combined with active light extraction components using liquid crystals [10], [11] and pixelated holograms [12], [13]. This new approach aims to offer a more flexible integration with the optical combiner and to increase the energy efficiency of AR glasses.…”