High density wavelength multiplexing within a passive optical interconnect allows multiple connections independent of bit rate and data format, providing service transparency and a high level of flexibility. A number of optical filtering technologies are available for channel access or selection. For WDM channels spaced in the 1 to 5 nm band using DFB lasers, interference filters or grating based demultiplexers provide the required performance for selectivity, crosstalk and insertion loss. The authors demonstrated a novel implementation of a grating demultiplexer in the form of a multichannel grating demultiplexer (MGD) receiver where a high (>60%) channel width/spacing ratio is achieved by the choice of detector dimensions. >