Abstract

The increased integration of optical devices into subsystems will lead to more compact, higher-functionality and lower-cost communication systems. An immediate DWDM systems application that would benefit from subsystem integration is the control of individual channel powers before the multiplexing function, ^1,2 as illustrated in Figure 1a. Several commercial products and concepts attempting to achieve this functionality have been presented^3,4 but none so far have been truly integrated solutions, because the variable optical attenuator (VOA) arrays are on separate chips to the multiplexer. These approaches necessitate multiple fiber connections between chips. The requirement for separate chips is due to the need to dissipate power from the VOA regions in such a way so as not to affect the operation of the demultiplexer, which is thermally sensitive, or due to the current incompatibility between the fabrication process for the AWG with some of those for VOA alternatives. The use of separate chips significantly increases the cost of manufacture and assembly.

© 2002 Optical Society of America