Abstract

The concept of using holograms or holographic devices to realize optical interconnection has been subjects of recent investigations [1,2]. In conventional holographic architectures, the holographic optical elements (HOEs) that interconnect signals between the input sources such as laser diodes (LDs) and the output receivers such as photodiodes, fibers, etc., are generally not located in the plane of the optoelectronic and VLSI elements. This type of 3D free-space holographic interconnect has important limitations. First, alignment problems are critical. If the sources and detectors are not in exact 3D alignment with the opposing holographic elements, performance suffers possibly to the point where the interconnect becomes inoperative. Second, and more importantly, even assuming ideal conditions, conventional Bragg holographic interconnect previously proposed cannot, in theory or practice, provide the large number of interconnections (N >> 10) needed in the typical VLSI systems. In short, the interconnectability of such bulk holographic system is limited by the small hologram thickness (∼10 to 20 μm).

© 1988 Optical Society of America