1-to-12 surface normal three-dimensional optical interconnects

Abstract

We present a surface normal optical interconnect with a l-to-12 collinear fan-out. Two types of polymer-based holograms were fabricated to provide a collinear l-to-12 fan-out from guided mode to substrate modes and twelve l-to-l surface normal interconnects. Fluctuation of up to 7.2 dB for the l-to-12 fan-out hologram was observed due to the oscillating and the film saturation effects of the transmission hologram. Diffraction efficiency better than 70% was observed for all the total internal reflection holograms. The result reported herein greatly enhanced optical signal processing capability of guided wave optical interconnects. The advantages of free space optical interconnect, such as global interconnect, three dimension, massive fan-out/fan-in capabilities, and surface normal optical interconnect, can be realized using the demonstrated architecture. The coupling from waveguide to fiber can be realized from the surface rather than the edge of a photonic integrated circuit.

Five-bit substrate guided wave true-time delay module working up to 2.4 THz with a packing density of 2.5 <inline-formula><roman>lines/cm</roman>^{<roman>2</roman>}</inline-formula> for phased array antenna applications

“…The two-beam interference method is used to define individual holographic gratings, each at a different recording angle, generating a sinusoidal phase modulation profile. [16][17][18][19] Here the recording and re- constructing parameters are selected so that the Bragg condition is satisfied. Therefore, there is only one diffraction order.…”

“…Each of the delay signal from the 1-to-4 beamsplitter is coupled into the substrate surfacenormally with a specific substrate bouncing angle through a holographic coupler and then zig-zags within the substrate through total internal reflection ͑TIR͒. 15,16 Portions of the substrate guided waves are sequentially extracted surfacenormally through a holographic output coupler array as shown in Fig. 2.…”

High packing density 2.5 THz true-time-delay lines using spatially multiplexed substrate guided waves in conjunction with volume holograms on a single substrate

“…The substrate bouncing angle depends critically on these two angles. To form a slanted grating coupler that converts a vertical incident wave to a TIR beam with a bouncing angle in the substrate, the two incident angles of the recording beams with respect to the surface normal of the film are described in [9].…”

“…These films exhibit properties such as a high diffraction efficiency, dry-processing after exposure and environmental stability. The two beam interference method is used to define individual holographic gratings [9], each at a different recording angle resulting in a sinusoidal phase modulation profile.…”

Polarization sensitivity of photopolymer-based volume holograms for one-to-many surface normal optical interconnects

“…13 An argon ion laser operating at 514 nm is used to record holograms. The reconstruction wavelength is set at 632.8 nm.…”