A technology is described for optical communication. An example of the technology can include receiving an event stream containing indications of independent events detected by pixels in an event camera. An event may be a change in brightness detected by a pixel in the pixel array, and the pixel independently generates an indication of the event in response to detecting the event. The event stream can be demultiplexed into a plurality of communication streams containing related events associated with a plurality of communication sources. The events contained in a communication stream can be aggregated based in part on an event proximity and an event time that associates an event with other events contained in the event stream. The plurality of communication streams can be demodulated to extract optically transmitted information from the plurality of communication streams, which can be sent to a data consumer.

Methods, systems, and devices for network communications to reduce optical beat interference (OBI) in upstream communications are described. For example, a fiber node may provide a narrow band seed source to injection lock upstream laser diodes. Therefore, upstream communications from each injection locked laser diode may primarily include the wavelength associated with each seed source. The seed sources may be unique to each end device and configured to minimize OBI. That is, the upstream laser diodes may be generic, but the received seed source may enable upstream communications at varying wavelengths. The fiber node may provide each seed source by filtering (e.g., by a grating filter) a broadband light source.

An active optical cable that allows bidirectional communication includes: a plurality of optical fibers; and a first optical module and a second optical module that are coupled via the plurality of optical fibers. The first optical module includes: at least one first light emitting element that emits laser light and a second light emitting element that also emits laser light; and a first modulator that modulates first laser light and converts the first laser light into first signal light. The first laser light is part of the laser light emitted by the at least one first light emitting element. The second optical module includes a second modulator that modulates second laser light and converts the second laser light into second signal light.

An active optical cable that allows bidirectional communication includes: a plurality of optical fibers; and a first optical module and a second optical module that are coupled via the plurality of optical fibers. The first optical module includes: at least one first light emitting element that emits laser light and a second light emitting element that also emits laser light; and a first modulator that modulates first laser light and converts the first laser light into first signal light. The first laser light is part of the laser light emitted by the at least one first light emitting element. The second optical module includes a second modulator that modulates second laser light and converts the second laser light into second signal light.

An optical system and method for seeding an optical transmitter includes a first optical transmitter comprising a first reflective optical amplifier and a second optical transmitter comprising a second reflective optical amplifier. The second optical transmitter is optically coupled to the first optical transmitter. The optical system also includes an optical cavity for seeding the first reflective optical amplifier with a first optical seed signal. The optical cavity is formed between the first reflective optical amplifier of the first optical transmitter and the second reflective optical amplifier of the second optical transmitter. The first reflective optical amplifier is configured to transmit a first optical signal to the second reflective optical amplifier and the second reflective optical amplifier is configured to provide the first optical seed signal by reflecting a portion of the first optical signal back to the first reflective optical amplifier.

According to an example aspect, there is provided an apparatus comprising a fibre interface coupled, via a first waveguide, with at least one encoder, a controller configured to cause the at least one encoder to encode light received in the apparatus via the fibre interface with information, and to cause a frequency shift in the light, and wherein the apparatus is configured to cause the light to propagate back to the fibre interface.

According to an example aspect, there is provided an apparatus comprising a fibre interface coupled, via a first waveguide, with at least one encoder, a controller configured to cause the at least one encoder to encode light received in the apparatus via the fibre interface with information, and to cause a frequency shift in the light, and wherein the apparatus is configured to cause the light to propagate back to the fibre interface.

A full duplex communication network includes an optical transmitter end having a first coherent optics transceiver, an optical receiver end having a second coherent optics transceiver, and an optical transport medium operably coupling the first coherent optics transceiver to the second coherent optics transceiver. The first coherent optics transceiver is configured to (i) transmit a downstream optical signal at a first wavelength, and (ii) simultaneously receive an upstream optical signal at a second wavelength. The second coherent optics transceiver is configured to (i) receive the downstream optical signal, and (ii) simultaneously transmit the upstream optical signal. The first wavelength has a first center frequency separated from a second center frequency of the second wavelength.

An injection locked transmitter for an optical communication network includes a master seed laser source input substantially confined to a single longitudinal mode, an input data stream, and a laser injected modulator including at least one slave laser having a resonator frequency that is injection locked to a frequency of the single longitudinal mode of the master seed laser source. The laser injected modulator is configured to receive the master seed laser source input and the input data stream, and output a laser modulated data stream.

Methods, systems, and devices for network communications to reduce optical beat interference (OBI) in upstream communications are described. For example, a fiber node may provide a seed source to injection lock upstream laser diodes. Therefore, upstream communications from each injection locked laser diode may primarily include the wavelength associated with each seed source. The seed sources may be unique to each end device and configured to minimize OBI. That is, the upstream laser diodes may be generic, but the collected seed source may enable upstream communications at varying wavelengths. The end device may provide upstream communications by externally modulating a signal generated by the injection locked laser diode.