Embodiments of the present invention provide a reconfigurable optical add/drop multiplexer, including: an input component, an output component, a beamsplitter, a first switch array, a wavelength dispersion system, a redirection system, and a second switch array. The input component includes M+P input ports, the output component includes N output ports, the beamsplitter is configured to: receive M input beams from M input ports, and split each of the M input beams into at least N parts, to obtain at least MN beams; the first switch array includes at least P switch units; and the second switch array includes N rows of switch units. The first switch array, the beamsplitter, the wavelength dispersion system, the redirection system, and the second switch array are arranged so that P optical add beams and sub-beams of MN beams in the at least MN beams can be routed to the N output ports.

A multi-path interference filter. The multi-path interference filter includes a first port waveguide, a second port waveguide, and an optical structure connecting the first port waveguide and the second port waveguide. The optical structure has a first optical path from the first port waveguide to the second port waveguide, and a second optical path, different from the first optical path, from the first port waveguide to the second port waveguide. The first optical path has a portion, having a first length, within hydrogenated amorphous silicon. The second optical path has a portion, having a second length, within crystalline silicon, and the second optical path has either no portion within hydrogenated amorphous silicon, or a portion, having a third length, within hydrogenated amorphous silicon, the third length being less than the first length.

A VCSEL transmitter includes aa first VCSEL terminal disposed on a substrate and a second VCSEL terminal adjacent thereto. The transmitter also includes a first diffraction element within a first optical path of the first VCSEL terminal which receives and changes a first direction of a first light transmission having a low-order Laguerre Gaussian mode emitted from the first VCSEL terminal. The transmitter further includes a second diffraction element within a second optical path of the second VCSEL terminal which receives the second light transmission and converts the received light into a high-order Laguerre Gaussian mode. The transmitter also includes a mode combiner to direct the first light transmission into a lens which directs the light into a multi-mode optical fiber.

A signal monitoring method and apparatus for a wavelength selective switch (WSS) are provided. The signal monitoring method for a wavelength selective switch WSS includes: encoding a phase of a first optical engine based on an input WDM signal, so that the WDM signal is split into a transmitted signal and a monitored signal after passing through the first optical engine; inputting the monitored signal to a second optical engine disposed at an output-side grating; and controlling the second optical engine to rotate in a wavelength plane of the WDM signal, so that monitored light of a specified wavelength in the monitored signal is output from the second optical engine at a preset angle.

An optical filter includes a spectroscopic element configured to disperse input light, and emit the dispersed input light as spectrum light; and an optical fiber including an end face having a recess, a core having a first face in contact with a bottom of the recess and a second face sandwiched between the first face and a circumference end of the recess, and a clad surrounding the core, wherein in the optical fiber, the recess is irradiated with the spectrum light, the second face is inclined such that a second portion incident from the second face to the core out of the irradiated spectrum light is emitted to the clad, and a first portion incident from the first face to the core out of the irradiated spectrum light is outputted.

The invention provides methods and apparatus comprising a multi-wavelength laser source that uses a single unfocused pulse of a low intensity but high power laser over a large sample area to collect Raman scattered collimated light, which is then Rayleigh filtered and focused using a singlet lens into a stacked fiber bundle connected to a customized spectrograph, which separates the individual spectra from the scattered wavelengths using a hybrid diffraction grating for collection onto spectra-specific sections of an array photodetector to measure spectral intensity and thereby identify one or more compounds in the sample.

Embodiments of the present invention provide a reconfigurable optical add/drop multiplexer, including: an input component, an output component, a beamsplitter, a first switch array, a wavelength dispersion system, a redirection system, and a second switch array. The input component includes M+P input ports, the output component includes N output ports, the beamsplitter is configured to: receive M input beams from M input ports, and split each of the M input beams into at least N parts, to obtain at least MN beams; the first switch array includes at least P switch units; and the second switch array includes N rows of switch units. The first switch array, the beamsplitter, the wavelength dispersion system, the redirection system, and the second switch array are arranged so that P optical add beams and sub-beams of MN beams in the at least MN beams can be routed to the N output ports.

Various methods, systems, and apparatuses, for optical switching are provided. For example, one wavelength selective switch (WSS) includes a plurality of optical ports wherein one or more optical ports are configured to receive one or more input optical beams the one or more input optical beams having a plurality of wavelength channels and wherein one or more of the optical ports are configured to receive one or more wavelength channels of the plurality of wavelength channels for output. The WSS also includes a polarization conditioning assembly, a polarization beam splitter assembly, a direction dependent polarization rotator, a polarization beam splitter, a grating, and a polarization modulator array having a plurality of polarizing modulation cells, each cell configured to independently change a polarization orientation of an optical beam passing through the cell.

According to one embodiment, a display device includes a first arrangement layer and a second arrangement layer. The first layer includes a first pixel, a second pixel, and a third pixel are arranged periodically in one direction. The second layer is opposed to the first layer, and the second layer includes a first element, a second element, and a third element which are arranged periodically to correspond to the first pixel, the second pixel, and the third pixel, respectively, and separate emission light to light of wavelength corresponding to a first color, light of wavelength corresponding to a second color, and light of wavelength corresponding to a third color to be emitted on the first pixel, the second pixel, and the third pixel, respectively.

We describe a space-division multiplexed (SDM) fibre, reconfigurable, wavelength-selective switch (WSS). The switch comprises a space-division multiplexed (SDM) optical input port to receive a space-division multiplexed (SDM) optical input signal comprising a plurality of space division modes each of said space division modes carrying a respective data signal, wherein each of said space division modes is also wavelength division multiplexed (WDM); an optical space division demultiplexer, coupled to said input port, to split said space-division multiplexed (SDM) optical input signal into a plurality of space division demultiplexed optical signals on separate demultiplexer outputs of said demultiplexer, each said demultiplexer output of said demultiplexer comprising a wavelength division multiplexed one of said plurality of space division modes; a set of reconfigurable wavelength-selective optical switches, each reconfigurable wavelength-selective optical switch having a switch input and a set of N switch outputs, and each including a dispersive element and a controllable beam steering element such that each said reconfigurable wavelength-selective optical switch is reconfigurable to selectively direct different respective wavelengths of a WDM optical signal at said switch input to different selected outputs of said set of N switch outputs, and wherein each said demultiplexer output is coupled to said switch input of a respective one of said set of reconfigurable wavelength-selective optical switches; and a set of optical space division multiplexers, one for each of said N switch outputs, each said optical space division multiplexer having a set of multiplexer inputs and a multiplexer output, to re-multiplex optical signals at said multiplexer inputs into a space-division multiplexed optical output signal at said multiplexer output, and wherein, for each of said set of optical space division multiplexers, each multiplexer input of said set of multiplexer inputs is coupled to said switch output of a different respective one of said set of reconfigurable wavelength-selective optical switches.