Abstract: A miniature monolithic optical demultiplexer that comprises a dispersive optical element and a wavelength filter array. The miniature monolithic optical DWDM demultiplexer can be fabricated using micro- and nano-scale techniques common to the semiconductor industry. The operating principles and some characteristics of the DWDM demultiplexer are described. The device will be useful in the field of optical communication as a component within networks that perform all of the necessary switching, adding, dropping, and manipulating of optical signals entirely in the optical domain. With the inclusion of additional components, exemplary optical communication devices that can be built using the DWDM demultiplexer include optical add/drop multiplexers (OADM), Dense Wavelength Division Multiplexing (DWDM) routers, tunable filters, optical cross connects, and the like.