The present invention discloses an optical fiber filter with an ultra-wide tuning range, comprising an input optical fiber, a two-dimensional mechanical rotating mirror, a collimating and beam expanding system, two gratings, and an output optical fiber. The input optical fiber emits a multi-wavelength optical signal into the two-dimensional mechanical rotating mirror, the optical signal is reflected to the collimating and beam expanding system to form collimated beams, the collimated beams are incident on the gratings which generate dispersion to scatter different wavelengths to different angles, and lights of different diffraction angles are input into the output optical fiber by adjusting the two-dimensional mechanical rotating mirror. In the present invention, a two-dimensional mechanical rotating mirror is used to switch gratings of different wavebands, which can realize tuning of optical wavelengths in an ultra-wide range. The application scenarios are greatly expanded, the cost is reduced, and the optical path is simple, which can realize fast tuning. In addition, the number of channels is expanded by multiplexing the time and space of a rotating device.

A system for the prevention of the transmission of classified data has a front panel containing a plurality of adapters, a rear panel containing a plurality of adapters, and at least one opto-isolator contained within the enclosure. The opto-isolator is connected via an optical fiber to a connector inserted into an adapter in the rear panel and also connected via a second optical fiber to a connecter inserted into one of the plurality of adapters in the front panel.

Embodiments disclosed herein include photonics systems with a dual polarization module. In an embodiment, a photonics patch comprises a patch substrate, and a photonics die over a first surface of the patch substrate. In an embodiment, a multiplexer is over a second surface of the patch substrate. In an embodiment, a first optical path from the photonics die to the multiplexer is provided for propagating a first optical signal, and a second optical path from the photonics die to the multiplexer is provided for propagating a second optical signal. In an embodiment, a Faraday rotator is provided along the second optical path to convert the second optical signal from a first mode to a second mode before reaching the multiplexer.

Apparatuses and methods associated with silicon photonic chips, are disclosed herein. In some embodiments, a quarter wave plate (QWP) is provided to a silicon photonic chip to convert a first linearly polarized mode (e.g., TE mode) optical beam from a laser disposed on the silicon photonic chip, into a combination of orthogonal polarization modes optical beam, and to convert or contribute in converting a reflection of the combined polarized modes optical beam into a second linearly polarized mode (e.g., TM) optical beam with polarization orthogonal to the first. The optical beam is rotated relative to an axis of the QWP, or the QWP and its axis are rotated relative to a polarization axis of the optical beam. Other embodiments are also described and claimed.

A miniaturized optical circulator includes: two polarized beam splitters and a 45-degree Faraday rotator, wherein an optical signal of a first optical path is input from a common terminal and is separated into a first polarization component and a second polarization component by a first polarized beam splitter, the first polarization component passes through the 45-degree Faraday rotator, reached a second polarized beam splitter and is reflected back, and passes through the 45-degree Faraday rotator and the first polarized beam, and reached a receiving terminal; the second polarization component under goes one reflection of the first polarization beam splitter subsequent to being separated, and reaches the receiving terminal; the optical signal of a second optical path is input, passes through the second polarized beam splitter, the 45-degree Faraday rotator, and the polarized beam splitter, and is output by the common terminal.

A photonic integrated circulator can be fabricated by including a plurality of polarizing beam splitters and optical polarization rotators such that two copies of the optical signal are output at a receiver in substantially aligned polarization states. The circulator can be used for facilitating bi-directional communications between photonic integrated circuit devices, which are inherently polarization sensitive, while reducing signal loss.

A magnetic field sensor element 30 has a first polarization maintaining fiber 31 separating the linearly polarized light into a first linearly polarized wave propagated along the first slow axis and a second linearly polarized wave propagated along the first phase advance axis faster than the first linearly polarized wave, and propagating the first linearly polarized wave and the second linearly polarized wave, a second polarization maintaining fiber 32 having a second slow axis and a second phase advance axis, and connected to the first polarization maintaining fiber so that the second phase advance axis and the second slow axis are inclined 45 degrees with respect to the first phase advance axis and the first slow axis, a Faraday rotator 33 optically connected to the second polarization maintaining fiber, and shifting a phase of circularly polarized light emitted from the second polarization maintaining fiber in response to magnetic field at which the magnetic field sensor element is disposed, and a mirror element 34 connected to the Faraday rotator, and generating the return light.

The present invention discloses an encoding apparatus, including: a polarization splitter-rotator PSR, a polarization rotation structure, and a modulator, where the PSR is configured to receive an input signal light, split the input signal light into two parts whose polarization modes are the same, and send the two parts to the polarization rotation structure and the modulator respectively; the polarization rotation structure has functions of rotating, by 180 degrees, a polarization direction of an optical signal entering the polarization rotation structure from one end, and keeping a polarization direction of an optical signal entering the polarization rotation structure from the other end unchanged; the modulator is configured to modulate a light input to the modulator; and the PSR is further configured to receive signal lights sent by the polarization rotation structure and the modulator, combine the two signal lights to send the output signal light.

A device includes an integrated structure of an input fiber, a first output fiber, an input splitting/combining device, a first output splitting/combining device, an input rotation device, a first output rotation device, a first lens, an isolator core, a second lens, a second output rotation device, a second output splitting/combining device, and a second output fiber. With the integrated structure, the device integrates functions of an optical isolator and an optical splitter. As an optical splitter, input of an optical signal into the input fiber are distributed to the two output fibers for output. As an optical splitter, the device can isolate light in opposite directions and can reduce damage to a light source at the input. In a system, the device can replace two conventional optical isolators and optical splitters and effectively reduce space, simplify the assembly process, and facilitate miniaturization and integration for systems.

An isolator includes a first waveguide with a linear shape and a second waveguide with an annular shape on a substrate including a substrate surface, the first waveguide being positioned along the substrate surface. The first waveguide and the second waveguide each include a core and a cladding. The first waveguide includes a first end, a second end, and a port at each of the first end and the second end for input and output of electromagnetic waves. The core of the second waveguide includes a non-reciprocal member in at least a portion of a cross-section intersecting a direction in which the second waveguide extends.