A single-ended output circulator includes a three-core optical fiber head having first, second, and third optical fiber cores; a walk-off crystal having a first surface facing towards the second end of the three-core optical fiber head tube and a second surface facing away from the second end of the three-core optical fiber head tube; a plurality of half-wave plates each having a first surface coupled to the second surface of the walk-off crystal and a second surface facing away from the second surface of the walk-off crystal; a collimating lens having a first end and a second end; a reflection mirror configured to reflect light beams from the collimating lens; an optical prism between the collimating lens and the reflection mirror and configured to transmit a light beam along a propagation direction according to a polarization direction of the light beam; and a polarization rotator.

In order to prevent a signal which a terminal station does not require from being intercepted by the terminal station without greatly changing the power of optical signals to be transmitted from a node to the terminal station, a node device is provided with: a first optical unit which outputs a first optical signal received from a first terminal station and addressed to a second terminal station, and a second optical signal received from the first terminal station, addressed to a third terminal station, and having a different wavelength band from the first optical signal; and a second optical unit to which the first and second optical signals outputted from the first optical unit are inputted, and which shifts the frequency of the first optical signal by a predetermined amount to create a fourth optical signal, passes the second optical signal without any change, couples the second and fourth optical signals, and transmits a resultant signal to the third terminal station.

A fiber optic sensor arrangement is disclosed that includes a plurality of optical fiber based sensor elements, the sensor elements configured to modify an associated optical carrier signal in accordance with changes in a sensed quantity at a location of the sensor element and a phase modulation arrangement for phase modulating each optical carrier signal in accordance with respective uncorrelated pseudorandom binary sequence signals. The sensor arrangement also includes an interferometer module for receiving each of the phase modulated optical carrier signals, the interferometer module operable to convert a change in the phase modulated optical carrier signals to a change in optical intensity of the corresponding optical carrier signal to generate a combined modulated optical intensity signal, an optical intensity detector for measuring the combined modulated optical intensity signal and generating a time varying electrical detector signal and an analog to digital convertor to convert the time varying electrical detector signal to a time varying digitized detector signal. Also included in the sensor arrangement is a decorrelator arrangement for decorrelating the time varying digitized detector signal against the respective uncorrelated pseudorandom binary sequence corresponding to each of the optical carrier signals to recover each of the modulated optical carrier signals and a demodulator for demodulating each of the modulated optical carrier signals to recover the respective optical carrier signal to determine the changes in the sensed quantity at the location of the sensor element.

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.

Exemplary apparatus can be provided which can include a laser arrangement that is configured to provide a laser radiation, and including an optical cavity. The optical cavity can include a dispersive optical waveguide first arrangement having first and second sides, and which is configured to (i) receive at least one first electro-magnetic radiation at the first side so as to provide at least one second electro-magnetic radiation, and (ii) to receive at least one third electro-magnetic radiation at the second side so as to provide at least one fourth electro-magnetic radiation. The first and second sides are different from one another, and the second and third radiations are related to one another. The optical cavity can also include an active optical modulator second arrangement which can be configured to receive and modulate the fourth radiation so as to provide the first electro-magnetic radiation to the first arrangement. The laser radiation can be associated with at least one of the first, second, third or fourth radiations.

An optical fiber filter has an ultra-wide tuning range and includes a two-dimensional mechanical rotating mirror, a collimating and beam expanding system, and two grating. An input fiber emits a multi-wavelength optical signal into the rotating mirror, which reflects the signal to the system to form collimated beams. In turn, the collimated beams are incident on the gratings that disperse the light of different wavelengths to different angles. Lights of different diffraction angles are input into an output fiber by adjusting the rotating mirror. The rotating mirror can be used to switch between gratings of different wavebands to tune optical wavelengths in an ultra-wide range.

Exemplary apparatus can be provided which can include a laser arrangement that is configured to provide a laser radiation, and including an optical cavity. The optical cavity can include a dispersive optical waveguide first arrangement having first and second sides, and which is configured to (i) receive at least one first electro-magnetic radiation at the first side so as to provide at least one second electro-magnetic radiation, and (ii) to receive at least one third electro-magnetic radiation at the second side so as to provide at least one fourth electro-magnetic radiation. The first and second sides are different from one another, and the second and third radiations are related to one another. The optical cavity can also include an active optical modulator second arrangement which can be configured to receive and modulate the fourth radiation so as to provide the first electro-magnetic radiation to the first arrangement. The laser radiation can be associated with at least one of the first, second, third or fourth radiations.

A single-ended output circulator includes a three-core optical fiber head having first, second, and third optical fiber cores; a walk-off crystal having a first surface facing towards the second end of the three-core optical fiber head tube and a second surface facing away from the second end of the three-core optical fiber head tube; a plurality of half-wave plates each having a first surface coupled to the second surface of the walk-off crystal and a second surface facing away from the second surface of the walk-off crystal; a collimating lens having a first end and a second end; a reflection mirror configured to reflect light beams from the collimating lens; an optical prism between the collimating lens and the reflection mirror and configured to transmit a light beam along a propagation direction according to a polarization direction of the light beam; and a polarization rotator.

A method of testing a photonic device includes providing a plurality of optical test signals at respective inputs of a first plurality of inputs of an optical input circuit located on a substrate, combining the plurality of optical test signals into a combined optical test signal at an output of the optical input circuit, transmitting the combined optical test signal through the output to an input waveguide of an optical device under test, the optical device under test being located on the substrate, and measuring a response of the optical device under test to the combined optical test signal. Each of the plurality of optical test signals comprises a respective dominant wavelength of a plurality of dominant wavelengths.

A photonic testing device includes a substrate, an optical device under test (DUT) disposed over the substrate, and an optical input circuit disposed over the substrate. The optical input circuit includes a first plurality of inputs each configured to transmit a respective optical test signal of a plurality of optical test signals. Each of the plurality of optical test signals includes a respective dominant wavelength of a plurality of dominant wavelengths. The optical input circuit further includes an output coupled to an input waveguide of the optical DUT. The output is configured to transmit a combined optical test signal comprising the plurality of optical test signals.