This application provides a tunable optical add/drop multiplexer T-OADM. A beam adjustment apparatus changes an incident angle at which an incident beam is emitted onto an optical filter. After the optical filter splits the incident beam into a transmitted beam and a reflected beam, the beam adjustment apparatus further adjusts a transmission direction of the transmitted beam emergent from the optical filter and a transmission direction of the reflected beam emergent from the optical filter, so that the transmitted beam and the reflected beam are output to corresponding ports, so as to implement a flexible and controllable T-OADM apparatus. This application may be applied to the optical communication field, for example, may be used to implement add/drop multiplexing of tributary signals in an optical domain in fields such as a long-haul backbone and a metropolitan area network.

A light module includes an optical element and a base on which the optical element is mounted. The optical element has an optical portion which has an optical surface; an elastic portion which is provided around the optical portion such that an annular region is formed; and a pair of support portions which is provided such that the optical portion is sandwiched in a first direction along the optical surface and in which an elastic force is applied and a distance therebetween is able to be changed in accordance with elastic deformation of the elastic portion. The base has a main surface, and a mounting region in which an opening communicating with the main surface is provided. The support portions are inserted into the opening in a state where an elastic force of the elastic portion is applied.

Examples described herein relate to an optical device, such as, a ring resonator, that includes a ring waveguide. The ring resonator includes a ring waveguide to allow passage of light therethrough. Further, the ring resonator includes a modulator formed along a first section of the circumference of the ring waveguide to modulate the light inside the ring waveguide based on an application of a first reverse bias voltage to the modulator. Moreover, the ring resonator includes an avalanche photodiode (APD) isolated from the modulator and formed along a second section of the circumference of the ring waveguide to detect the intensity of the light inside the ring waveguide based on an application of a second reverse bias voltage to the APD. The second section is shorter than the first section, and the second reverse bias voltage is higher than the first reverse bias voltage.

A system including wavelength multiplexers. In some embodiments, the system includes: a first multiplexing element, having a first plurality of input waveguides, each configured to receive light at a respective wavelength of a first plurality of wavelengths; and a second multiplexing element, having a second plurality of input waveguides, each configured to receive light at a respective wavelength of a second plurality of wavelengths. A wavelength of the second plurality of wavelengths may fall between a first wavelength of the first plurality of wavelengths and a second wavelength of the first plurality of wavelengths.

A waveguide division multiplexer and demultiplexer includes a first-stage Mach-Zehnder interferometer (MZI) and two second-stage MZIs. The first-stage MZI includes two input ends and two output ends, in which one of the inputs is configured to receive an input optical beam with a first center wavelength and a second center wavelength, and the output ends are configured to respectively transmit first-stage output optical beams respectively with the first center wavelength and the second center wavelength. One input terminals of the second-stage MZI are configured to respectively receive the first-stage output optical beams, and one output terminals of the second-stage MZI are configured to transmit second-stage output optical beams with the first and second center wavelengths, respectively. Each second-stage MZI is configured in cross-state condition.

A delivery fiber assembly suitable for delivering broad band light and including a delivery fiber and a connector member. The delivery fiber has a length, an input end for launching light, and a delivery end. The delivery fiber includes along its length a core region and a cladding region surrounding the core region, the cladding region includes a cladding background material having a refractive index N.sub.bg and a plurality of microstructures in the form of inclusions of solid material having refractive index up to N.sub.inc and extending in the length of the longitudinal axis of the delivery fiber, wherein N.sub.inc<N.sub.bg. The plurality of inclusions in the cladding region is arranged in a cross-sectional pattern including at least two rings of inclusions surrounding the core region. The connector member is mounted to the delivery fiber at a delivery end section of the delivery fiber including the delivery end.

The invention refers to an optical device for heterodyne interferometry, comprising a chip, a beam splitter, a first waveguide arranged on the chip, light propagating in the first waveguide being guided to the beam splitter, a second waveguide arranged on the chip, light propagating in the second waveguide being guided to and/or from the beam splitter, wherein the beam splitter, the first waveguide, and the second waveguide form part of a Michelson interferometer, wherein the first waveguide and the second waveguide at least partially form two arms of the Michelson interferometer, and wherein two further arms of the Michelson interferometer are at least partially arranged outside the chip.

The disclosed flow cytometer includes a wavelength division multiplexer (WDM). The WDM includes an extended light source providing light that forms an object, a collimating optical element that captures light from the extended light source and projects a magnified image of the object as a first light beam, and a first focusing optical element configured to focus the first light beam to a size smaller than the object of the extended light source to a first semiconductor detector. The disclosed flow cytometer further includes a composite microscope objective to direct light emitted by a particle in a flow channel in a viewing zone of the composite microscope to the extended light source, a fluidic system and a peristaltic pump configured to supply liquid sheath and liquid sample to the flow channel, and a laser diode system to illuminate the particle in the flow channel.

A wavelength division multiplexer/demultiplexer, a photonic integrated chip, and an optical module are provided. The wavelength division multiplexer/demultiplexer includes a substrate, a bus waveguide provided on the substrate, and at least two wavelength division multiplexing/demultiplexing units provided on the bus waveguide. Each of the at least two wavelength division multiplexing/demultiplexing units includes a mode multiplexer and an asymmetric Bragg grating. The mode multiplexer includes a first port, a second port, and a third port. The third port is connected to the asymmetric Bragg grating, so as to input a light in a TE1 mode or a higher-order mode to the asymmetric Bragg grating. The asymmetric Bragg grating transmits light containing wavelengths other than a wavelength λi. A grating period of the asymmetric Bragg grating and the wavelength λi satisfy a resonance condition.

Structures for a wavelength division multiplexing filter and methods of fabricating a structure for a wavelength division multiplexing filter. The structure includes a first waveguide core having a first section and a second section. The first section and the second section have a first notched sidewall and a second notched sidewall opposite to the first notched sidewall. The structure further includes a second waveguide core positioned with a first offset in a first direction relative to the first section and the second section of the first waveguide core and with a second offset in a second direction relative to the first section and the second section of the first waveguide core. The second direction is transverse to the first direction.