Crosstalk noise reduction of angle-multiplexed volume-holographic gratings for see-through lightguide display.

Angle multiplexing is a crucial technique for volume holographic gratings in grating-based lightguide display systems, enabling an extended image field of view (FOV). However, Bragg mismatch diffraction caused by different angle-multiplexed gratings introduces crosstalk, leading to ghost images. In this paper, we analyze the underlying causes of ghost image formation due to angle-multiplexed gratings and propose an optimized recording method to minimize crosstalk noise. Our approach ensures that each recorded volume grating generates a uniform grating vector across the surface of the holographic film, resulting in consistent grating periods among all angle-multiplexed gratings. This uniformity corrects the diffraction angles of crosstalk, aligning them with the original signal diffraction angle and effectively suppressing ghost images.