Design of substrate-mode holographic interconnects with different recording and readout wavelengths

A method for recording a substrate-mode holographic interconnect system, composed of two identical holographic optical elements (HOEs) which were recorded on the same plate, has been developed. Since the possible recording wavelengths for efficient holograms are usually different from the readout wavelengths, the holographic elements must be recorded with predistorted wavefronts to assure high diffraction efficiencies and low aberrations. The predistorted wavefronts are derived from simple spherical holograms whose readout geometries differ from those used during recording. The method is illustrated with HOEs recorded at 488 nm and read out at 633 nm. Nearly diffraction-limited imaging and high efficiencies were achieved.