Vertical-cavity surface-emitting lasers and smart pixels for optical interconnection systems
Though TDM (and recently WDM) are generally adopted to increase the total throughput in optical communication systems, SDM must be more effective in most optical interconnection systems. This is because SDM has more advantage in cost and power consumption than TDM, when the transmission distance is rather short, i.e. less than a few hundred meters. VCSEL and smart pixel arrays are very important for constructing optical interconnection systems because they can emit, switch and process a number of broadband optical signals simultaneously. This paper reviews VCSELs and VCSEL-based smart pixels, and discusses the issues for their application to optical interconnections. VCSELs and smart pixels are applicable to three types of parallel optical interconnections: 1) parallel optical fiber link-the optical signals from the SEL array are transmitted through a fiber ribbon for distances less than a few hundred meters; 2) free-space optical interconnects-high-density optical signals from a two-dimensional SEL array are distributed into several ports for distance shorter than one meter; 3) reconfigurable optical interconnects nterconnect patterns among processors are changed dynamically by means of free-space photonic switching networks.
POLO-parallel optical links for gigabyte data communications
A collaborative effort by the parallel optical link organization (POLO), a consortium of Hewlett-Packard, AMP, Du Pont, SDL, and the University of Southern California, to develop 10-20 Gb/s parallel optical links is described. The POLO consortium is supported by the advanced research projects agency (ARPA) and will operate between August 1994 and August 1997. Individual strengths of the consortium members are leveraged to develop affordable, high performance parallel optical interconnect modules for computer cluster, multimedia, and switching systems. The POLO consortium has also formed a User Group of seven leading computer and telecommunications companies to evaluate the POLO parallel optical link and provide feedback to the consortium.
Natural history and long‐term evolution in families with autosomal dominant cortical tremor, myoclonus, and epilepsy
Purpose:  To investigate for the first time the natural history and long‐term evolution of “familial cortical tremor, myoclonus, and epilepsy.”