Status of Leaky Mode Holography

Abstract

It will soon be a decade since leaky mode waveguide devices were presented as a solution for holographic video displays. This paper seeks to provide a brief, topical review of advances made during that time. Specifically, we review the new methods and architectures that have been developed over this period. This work draws primarily from papers seeking to present dynamic holographic patterns using mode coupling from indiffused waveguides on lithium niobate. The primary participants during this time period have been groups from the Massachusetts Institute of Technology, Brigham Young University, and Draper. We also describe the challenges that remain. The body of work reviewed speaks to the need for further development, but it also reaffirms that leaky mode waveguides continue to hold a unique place within spatial light modulation for holographic video displays.

Research Progress of Large Viewing‐Area 3D Holographic Near‐Eye Display

“…where 𝛽 guided and K grating were the propagation constant of input light and SAW, respectively, and 𝛽 leaky was the propagation constant component along the waveguide of the leaky mode light. The superposition of SAW could offer arbitrary holographic patterns required for the display, [119] and the holographic stereograms obtained from the leaky mode modulator are shown in Figure 10b. Then, several waveguide channels (or modulators) could be aggregated to provide the required display size and resolution (Figure 10c).…”

“…The guided polarized input light encountered the counter‐propagating SAW, and then the acoustooptic interaction resulted in a leaky mode light outputting at a high deflection angle when satisfying a phase‐matching condition [ 118 ] : $$$$\begin{equation} {\beta}_{\mathrm{guided}}\ -\ \ {K}_{\mathrm{grating}}=\ {\beta}_{\mathrm{leaky}}\ \ \end{equation}$$$$where $${{{\beta}}}_{{\mathrm{guided}}}$$ and $${K}_{\mathrm{grating}}$$ were the propagation constant of input light and SAW, respectively, and $${{{\beta}}}_{{\mathrm{leaky}}}$$ was the propagation constant component along the waveguide of the leaky mode light. The superposition of SAW could offer arbitrary holographic patterns required for the display, [ 119 ] and the holographic stereograms obtained from the leaky mode modulator are shown in Figure 10b. Then, several waveguide channels (or modulators) could be aggregated to provide the required display size and resolution (Figure 10c).…”