5 Fused Silica Micro-Components allow easy fiber insertion with minimal risk of damaging the cleaved or polished fiber ends. The precision bore allows excellent alignment of two fiber ends when they are inserted from opposite ends of the coupler. Figure 5-8 Dual Fiber Ferrule
Another type of coupler ferrule is used in WDM and other applications where two fibers need to be aligned side by side very accurately. Thermal, mechanical and optical parameters must be taken into account. A quartz capillary with a center that has a rectangular shape or precision separate dual ID’s can be fabricated. The entrance has a taper to simplify alignment when the two fibers are inserted. For other multiple fiber applications, the quartz tube can have a variety of shapes. With appropriately engineered preforms, Polymicro can produce various geometries including square, circular, elliptical, rectangular and triangular shapes.
Connectors, Ferrules & Splices - For Capillaries For coupling capillary tubing Polymicro offers Inner-Lok™ Capillary Connectors. These connectors are designed for quick, contamination-free coupling of polyimide coated silica capillary tubing in applications such as Gas Chromatography. Two standard products are available, a universal union and a Y-shaped splitter. The capillaries are inserted into the tapered ends and press fit to seal. If needed, a drop of adhesive or polyimide can be applied into the tapered ends to help hold the capillary (appropriate curing may be required). Proper cleaving is essential to form a good seal and is discussed in the Cleaving Procedure section of this Handbook’s Appendix. Polymicro’s standard InnerLok™ products have a 2mm outside diameter and are nominally 38mm long. They are designed to accept tubing with OD’s ranging from 360µm to 670µm. Custom sizes of Inner-Lok™ style connectors can be manufactured.
Figure 5-9 Capillary Inner-LokTM
Although less common, Ferrules and Splices like those used on Optical Fibers can be employed with capillary tubing. In many cases an existing larger size capillary tubing can be used as the ferrule or splice component. Custom tubing can be drawn to provide an exact fit if needed. Polymicro is well experienced with cutting, polishing, and flaring ferrules prior to use. These preparatory operations can reduce manufacturing time and improve final product quality. In addition, Polymicro can do the final assembly operations if needed; see Fiber Optic & Capillary Assemblies.
Special Capillaries - Multi-lumen Multi-lumen or multi-element capillaries are a class of flexible quartz or glass capillary tubing having multiple passageways. The number, size, and shape of the individual passageways depend on the application requirements. One can be used to guide an optical fiber for illumination at the distal end, while another can guide a gas or another instrument. The openings do not have to all be the same size.
Special Capillaries - Square/Rectangular Polymicro introduced a flexible silica square capillary in response to requests from the capillary electrophoresis (CE) scientific community. This square capillary offers an improved optical beam-sampling path over traditional circular cross-section silica capillaries for in line spectrometry. This square configuration allows for a simplified optical system for the spectrometer due to the lack of cylindrical lens effects found in normal round tubing. See the Flexible Fused Silica Capillary Tubing section of this handbook under Alternative Cross-Sectional Geometries for more details.
Special Capillaries - Windowed Capillaries Polymicro also supplies windowed silica capillary. The window is made using a laser-based technique to completely remove the polyimide while leaving the silica capillary extremely strong with excellent optical surface qualities. See the Flexible Fused Silica Capillary Tubing section of this handbook under Capillary Productss for more details.
MEMS/NEMS Technologies Polymicro is constantly evaluating and supporting emerging technologies, including the areas of Micro- and NanoElectro Mechanical Systems. Polymicro is integrally involved in a number of applications in this arena.
Inner-LokTM is a registered trademark of Polymicro Technologies © Polymicro Technologies, a Subsidiary of molex.
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