Use of laser-diode arrays in holographic interconnections.

Holographic interconnection schemes for high-speed data transfer have been demonstrated by other researchers. Because holographic recording materials presently available are sensitive to the visible spectrum but not to the near infrared, these studies used bulky gas lasers. Visible laser diodes, as they become available, will likely become a preferred source in a practical system because of their small size and high beam powers. The two mutually coherent beams needed to write the hologram have previously been implemented by using bulk optics to split a beam. In anticipation of the use of coherently coupled visible laser diode arrays as sources, it is shown that the individual elements of laser diode arrays currently available have sufficient mutual coherence to create reasonable holographic elements. This application is demonstrated with an infrared array because of the unavailability of visible arrays in this emerging technology. It is extrapolated that for visible coherently coupled laser diode arrays and current holographic materials, a holographic interconnection system is potentially feasible by using the mutually coherent beams from individual facets. This makes recording holograms more straightforward because the recording process eliminates beam splitting requirements. Therefore the system is more desirable for in situ recording situations such as those required for dynamic interconnection.