Waveguide displays are a popular architecture for optical see-through augmented reality (AR) devices because they provide a large eyebox while maintaining a compact form factor. However, they typically suffer from some drawbacks, including low optical efficiency and limited image quality, especially toward the edges of the field of view. Low optical efficiency reduces the brightness seen by the user and makes AR devices difficult to use in brighter environments, particularly outdoors. Poor image quality reduces the amount of detail that can be displayed through an AR device, limiting their range of application to showing large text and low-resolution figures. High efficiency and sharp image quality are difficult to achieve simultaneously in waveguide displays, requiring tradeoffs in the design process and the system specifications. In this work, we investigate how these parameters are impacted by the waveguide's geometry and choices about the diffractive gratings used. We show an example of a starting architecture and how to optimize performance by dividing the in-coupler into multiple zones without altering the overall waveguide geometry. Splitting the in-coupler into multiple zones opens a new dimension for exploring and expanding the waveguide design space.
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