Keying may be used to indicate various features of cables, cable connectors, and/or equipment. The keying mechanisms of the connectors systems disclosed herein identifies whether each plug is a pinned plug or a pinless plug. The keying mechanisms disclosed herein identify the number of optical fibers terminated at each plug. For example, one type of keying mechanism may indicate a cable plug manufactured under a 40 Gb/sec standard and another type of keying mechanism may indicate a cable plug manufactured under a 100 Gb/sec standard. The keying mechanisms may indicate a cabling/wiring pattern to be used (e.g., indicates a polarity of the cable). The cables and/or plugs may be color coded based on the keying mechanism. Accordingly, the keying may alert a user to the features of the cable that are not readily apparent upon a cursory inspection.

An optical connector includes a first attachment area for receiving and permanently attaching to an optical waveguide. A light coupling unit is disposed and configured to move translationally and not rotationally within the housing of the connector. The light coupling unit includes a second attachment area for receiving and permanently attaching to an optical waveguide received and permanently attached at the first attachment area. The light coupling unit also includes light redirecting surface. The light redirecting surface is configured such that when an optical waveguide is received and permanently attached at the first and second attachment areas, the light redirecting surface receives and redirects light from the optical waveguide. The optical waveguide limits, but does not prevent, a movement of the light coupling unit within the housing.

A multi-fiber, fiber optic connector may include a reversible keying arrangement for determining the orientation for plugging the connector into an adapter to thereby allow for a change in polarity of the connection to be made on site. The connector housing may be configured to engage with a removable key that may be engaged with the housing in at least two different locations to provide the plug-in orientation, or the housing may have slidably displaceable keys movable between multiple positions on the housing.

A fiber optic adapter assembly is provided with a floating adapter module. The adapter assembly includes a housing, an adapter module, and a single biasing member disposed in the housing and concentrically aligned with the adapter module. The single biasing member can bias the adapter module in a direction toward an end of the housing and be compressible in the opposite direction toward the other end of the housing.

A fiber optic connector along with a tool allows for the changing of the polarity of the fiber optic connector. Keys may be installed in both the top and the bottom of the fiber optic connector, one in a first position and the other in a second position. Using the tool in one back-and-forth motion, the polarity of the fiber optic connector can be changed. The keys have a configuration that resist an incorrect insertion and provide better retention of the keys in the correct configuration due to a better retention force.

Example fiber optic connector systems have rugged, robust designs that are environmentally sealed and that are relatively easy to install and uninstall in the field. Some connector systems can be configured in the field to be compatible with different styles of fiber optic adapters. Some connectors include a first seal (90) on a release sleeve; and a second seal (88) between the release sleeve and a connector body. Other connectors include a seal (139) and a flexible latch (136) on a connector. Other connectors include a protective structure (228, 328, 428) that mounts over the fiber optic connector. Other connectors include a protective outer shell (528, 860) and a sealing and attachment insert (570, 570A, 876). Other connectors include a protective outer shell (728) and a fastener (780).

An optical connector holding two or more LC-type optical ferrules is provided. The optical connector includes an outer body, an inner front body accommodating the two or more LC-type optical ferrules, ferrule springs for urging the optical ferrules towards a mating receptacle, and a back body for supporting the ferrule springs. The outer body and the inner front body are configured such that four LC-type optical ferrules are accommodated in a small form-factor pluggable (SFP) transceiver footprint or eight LC-type optical ferrules are accommodated in a quad small form-factor pluggable (QSFP) transceiver footprint. A mating receptacle (transceiver or adapter) includes internal alignment slots configured to accept a corresponding alignment key on connector outer housing to ensure alignment and orientation for maximum signal transfer between opposing ferrule end faces.

Fiber optic connection assemblies that may include hybrid adapters and connector assemblies are generally described. The hybrid adapter may be configured to connect a first connector type and a second connector type, the first connector type being different from the second connector type. For example, the first connector type may be a micro connector and the second connector type may be an LC connector. A connector assembly may be configured as a micro connector having a tension element configured to facilitate optimized optical performance by spring loading the ferrules while maintaining a small form factor.

A fiber optic adapter includes a surrounding wall defining a communication space, two first protruding walls located in the communication space and connected to the surrounding wall, two second protruding walls located in the communication space and connected to the surrounding wall, and an error-proofing protrusion disposed on the surrounding wall, and located in a first key groove between the first protruding walls.

A connector mating system that can enable the coupling and decoupling of electrical or optical power and communications channels, while in a harsh or submerged environment during which time the contacting interfaces of the power and communication channels remain fully protected from the destructive effects of the said environment. The system features a hybrid optic and/or electric connector that provides a means for electrical, optical and hybrid inter connection within an extremely hostile environment across a broad market range of applications with a novel end-seal concept in a scalable form factor with minimal actuation stresses and designed for high volume commodity manufacturing.