Optical Array Knowledge

A regular optical fiber array includes a V−grooved substrate for holding a plurality of optical fibers (up to hundreds) and a lid for pressing the fibers arranged in the grooves. The special adhesive is applied to the grooves to fix the fibers and the back part of the substrate to work as a strain relief area. Thus, even under the condition of high temperature and high humidity, no great stress is generated in the adhesive. Consequently, no crevice is generated between the fixing substrate and the adhesive, and accordingly, no peeling off is generated by the intrusion of water.

Normally, an optical fiber array has a polished optical coupling facet where another optical path is coupled to it.

Fiber core pitch accuracy is the critical feature of fiber array, either it is for the 2D fiber array or the V groove fiber array. Given that the variations in the fiber core/cladding geometry may cause offset errors, the specification for the tolerances of the fiber core positions cannot be explicitly specified. What MEISU does is having the size of grooves and the space between them well calculated according to the radius of the fiber. There is a formula on the minimum depth of the V-grooves, which related with the fiber radius and the opening space of the grooves. As long as the fibers are properly touching the two sides of the V-groove and the bottom of the lid, the +/-0.5um pitch tolerance can be effectively guaranteed.

The most common use of the V-Groove arrays is for planar waveguide devices such as PLC Splitter and AWG. Over the past few years, Linear (one-dimension) optical fiber array has been extensively applied in optical communication, optical imaging, and detection systems.