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The performance of optical interconnections and wavelength-
division-multiplexing (WDM) device is limited by signal
transmission fanout densities and capacity. Holographic optical
elements have good characteristics for free-space optical
interconnections and WDM, including high diffraction
efficiency, combined several optical functions and ease of
fabrication to solve these problem. In this dissertation, the
large fanout optical interconnection elements that utilize the
diffraction from volume hologams, and the symmetrical off-axis
and substrate-mode structure have been described. Techniques
for making tunable focal power elements and beam compression
connectors are disscused and experimentally fabricated in
bleach silver halide and dichromated gelatin emulsions. These
devices should lead to more efficient optical interconnection
architecture that would be more suitable for optical
implementation. WDM involves the transmission of a number of
different peak wavelength optical signals in pacallel ot a
single optical fiber. Bragg diffraction, angular dispersion and
total internal reflection propagation by substrate-mode
holograms have been used to demonstrate a large channels of WDM
device. The major implementations of wavelength-division-
multiplexing /demultiplexing devices with transmission- and
reflection-type substrate-mode grating pairs are discussed and
compared with particular emphasis placed on their optical
efficiency, crosstalk performance and the number of channels
that may be provided. We have desiged and fabricated WDM
devices that are implemented by polarization-insensitive high-
efficiency substrate-mode hologram. Based on the above schemes,
multi-channel devices, which exhibits low insertion loss and
crosstalk attenuation, has been demonstrated. In addition, the
design of WDM using the cascaded structure of substrate-mode
holograms is also presented. The design can increase the
transmission capacity more efficiently.
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