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.

An indexed cable arrangement can be installed in a re-enterable housing. The optical fibers of the cable are indexed between a first; ruggedized multi-fiber connector and a second multi-fiber connector. The second multi-fiber connector may be non-ruggedized and disposed within the housing (e.g., at an adapter) or ruggedized and disposed external of the housing (e.g., terminating a stub cable). One or more drop lines are terminated by respective non-ruggedized, single-fiber connectors disposed within the housing. In certain examples, drop lines may be split into multiple connectorized single-fiber outputs.

A fiber optic adapter assembly reduced in size from a SFP footprint to a SC footprint to accommodate a first fiber optic connector on a first side within one or more ports, and a second fiber optic connector on a second side within one or more ports. The first fiber optic connector is a duplex fiber optic connector with an overall length of about 50 mm and the second fiber optic connector is a behind-the-wall connector with an overall length of about 15 mm thereby reducing the overall length of a connector and adapter assembly for increasing optical fiber density.

An optical connector mechanism includes an abutting portion that applies a pressing force so as to cause an end surface of a first optical transmission and reception path and an end surface of a second optical transmission and reception path to abut against each other, a first case that houses the first optical transmission and reception path, a second case that houses the second optical transmission and reception path, a sleeve case slidably attached to the first case, an elastic bar member including one end portion fixed to the first case and another end portion to be inserted into the second case, an engagement portion that engages the other end portion of the elastic bar member with the second case, and an engagement releasing portion that presses the elastic bar member so as to release the engagement performed by the engagement portion when the sleeve case slides.

An expanded beam (EB) optical connector. In some embodiments, the EB optical connector includes: a rigid, hollow, straight contact tube having a centerline axis; and a collimator assembly having an optical axis and comprising an optical fiber and a collimating lens, wherein the centerline axis of the contact tube is at least substantially aligned with the optical axis such that collimated light produced by the lens from light exiting the fiber travels though the contact tube and the loss of light caused by misalignment of the axes is not more than 2 dB.

An optical connection includes a plurality of ferrules, an optical contact to allow transfer of light, a mechanical contact to allow torque transfer from the optical connection, and a rotational self-alignment structure to allow optical fibers of different optical connectors to self-rotate into rotational self-alignment upon action of connecting, wherein the ferrules are aligned and engage the torque transfer. The rotational self-alignment structure can be a tooth configuration, a helical thread configuration, a ferrule guide configuration, a spring sleeve configuration, derivatives thereof and combinations therefrom.

An adapter assembly includes a single-piece or two-piece multi-fiber adapter defining a recess at which a contact assembly is disposed. The adapter assemblies can be disposed within adapter block assemblies or cassettes, which can be mounted to moveable trays. Both ports of the adapters disposed within adapter block assemblies are accessible. Only one port of each adapter disposed within the cassettes are accessible. Circuit boards can be mounted within the block assemblies or cassettes to provide communication between the contact assemblies and a data network.

An optical fiber connection structure includes: a multi-core fiber; a plurality of single-core fibers; a first lens having a focal length of f1 (mm); and a second lens having a focal length of f2 (mm). A core pitch of the multi-core fiber is P1 (μm), a mode field diameter on the first end face of each core is MFD1 (μm), a core pitch of multiple single-core fibers is P2 (μm), a mode field diameter of a light beam on the second end face of each core is MFD2 (μm), and the following formulas are satisfied.

(P1/P2)×0.9≤f1/f2≤(P1/P2)×1.1, and

(P1/P2)×0.9≤MFD1/MFD2≤(P1/P2)×1.1

A telecommunication enclosure includes an environmentally sealed housing having an interior volume. The sealed enclosure includes a housing wall defining an opening that extends from the interior to an exterior of the enclosure, the housing wall defining interior threads within the opening. A port-defining element mounts within the opening, the port-defining element defining exterior threads that are threadingly mated with respect to the interior threads to retain the port-defining element within the opening. The port-defining element defines a connector port for receiving a hardened fiber optic connector.

Fiber optic connectors and junctions between fiber optic connectors include ferrules terminating a plurality of optical fibers, the ferrules having a ferrule keying portion that rotationally aligns and constrains the ferrules with a guide keying portion of an annular guide tube. The ferrules may further aligned and constrained and aligned in a lateral direction with a ferrule sleeve in the junction of connectors. Each of the ferrule sleeve and the guide keying portion individually constrain movement of the ferrules in different dimensions, the guide keying portion rotationally aligning and constraining the ferrules, while allowing freedom of movement in a lateral direction, and the ferrule sleeve aligning and constraining the ferrules in the lateral direction, while allowing rotational freedom of movement.