The technical issues involved in applying vertical-cavitysurface-emitting lasers (VCSEL's) to parallel opticalinterconnection systems are discussed from the viewpoint of theirapplication to asynchronous transfer mode switching and parallelcomputer systems. We also discuss approaches to designing a VCSELarray structure for high-speed modulation and the effect ofpixel-performance homogeneity on the transmission bandwidth and powerconsumption. We review monolithic and hybrid integrationtechnologies for VCSEL-based smart-pixel arrays, and we estimate themaximum pixel number and input-output throughput allowed in a chip, considering the power consumption and pixel homogeneity. We showthat a one-chip optoelectronic parallel processing system comprisingmore than 1000 processor elements is possible when smart-pixel arraysare fabricated under the 0.25-mum complementary metal-oxide semiconductor design rule.