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.

An embodiment includes a host-equalized optical transceiver. The host-equalized optical transceiver includes a driver analog interface, a linear laser diode driver (LLDD), and an optical transmitter. The driver analog interface is configured to interface with a host integrated circuit (IC) of a host system. The LLDD is directly electrically coupled to a host IC of the host system via the driver analog interface. The LLDD is configured to receive an equalized electrical data signal directly from the host IC via the driver analog interface and to generate a driving signal based on the equalized electrical data signal. The equalized electrical data signal is a linear signal. The optical transmitter is electrically coupled to the LLDD. The optical transmitter is configured to receive the driving signal from the LLDD and to generate an optical signal that is representative of the driving signal.

An electro-optic transceiver module, method of manufacturing, and method of transmitting signals are provided that allow multiple optical signals at different wavelengths (e.g., according to CWDM) to be combined for transmission via a number of optical fibers that is smaller than the number of electrical channels according to which the optical signals were generated. Thus, CWDM may be used in connection with lower-cost VCSEL technology (e.g., as opposed to higher-cost edge-emitting lasers) by providing for wavelength compensation at the VCSEL driver to offset any changes in wavelength that may have otherwise occurred at the VCSELs. In particular, a microcontroller of the electro-optic transceiver module correlates a monitored temperature of the VCSELs to an actual wavelength of the corresponding optical signals transmitted by the respective VCSELS and determined an adjustment in a current supplied by the VCSEL driver to each VCSEL to achieve more precise and consistent wavelengths at the VCSELs.

The present invention belongs to the technical field of underwater communication, and provides a novel highly robust underwater optical communication system which comprises a sending module and a receiving module. The novel highly robust underwater optical communication system realizes highly robust underwater optical communication under strong interference of sunlight and artificial light sources. The system uses a new physical method irrelevant to frequency, and can be used with existing MIMO and CDMA to obtain better communication effects. The circularly polarized light is used for signal transmission, thereby avoiding the problem of channel misalignment caused by the rotation of a platform underwater. At the same time, good polarization maintaining of a marine environment makes the signal characteristics difficult to lose.

Methods an systems for low-power transmission include biasing an emitter in a non-linear operating range of the emitter near a threshold current of the emitter. A data signal is distorted to add a precursor pulse to a rising edge of a data waveform to quickly bring the emitter into a linear operating range. The distorted data signal is transmitted at the emitter.

A method, system and an apparatus for hybrid optical and electrical pumping of semiconductor lasers and light-emitting diodes (LEDs) improves reliability at high operating temperatures. The semiconductor laser or LED is biased via optical pumping and a relatively small electrical modulation current modulates the laser. At low modulation speeds, the modulation current is substantially lower than that required for biasing the laser or directly modulating it at high speeds. The lifetime of the laser is improved by substantially reducing the operating current, enabling laser lifetimes adequate for operation in many applications, such as deep-hole oil drilling and jet engine control, where operation is not currently possible.

A connector which serves as an optical transmitter in accordance with an embodiment of the present invention includes: a transmitting circuit configured to convert a data signal into an electric current signal, the data signal being a three-valued; and an LD configured to convert the electric current signal into an optical signal. The transmitting circuit detects, as an IDLE interval, an interval during which the data signal falls within a predetermined range that is between a high level and a low level. The transmitting circuit controls, during the IDLE interval, the electric current signal to be not greater than a threshold electric current of the LD.

A drive circuit of a light emitting element, the drive circuit includes: an input terminal configured to receive an input signal; an output terminal configured to output a signal based on the input signal as a drive signal to the light emitting element; and a main body circuit configured to generate the drive signal by carrying out timing correction to reduce a difference from a standard delay value for rising or falling of a plurality of signal patterns of the input signal regarding a timing of rising of a first signal subsequent to a first signal pattern in the plurality of signal patterns or a timing of falling of a second signal subsequent to a second signal pattern in the plurality of signal patterns.

A driving element which performs driving according to a level of a voltage signal to be transmitted optically, a modulation current driving circuit configured to supply a modulation current modulated by the driving element to a light source for optical communication configured to convert a current signal into light and to output the light, and a constant current supply circuit configured to supply a constant current to the light source for optical communication are included. Then, when the voltage signal is at a first level, the driving element is turned on and the modulation current driving circuit supplies the modulation current to the light source for optical communication. When the voltage signal is at a second level, the driving element is turned off and the modulation current driving circuit stops supplying the modulation current. The present technique can be applied, for example, to an optical transmission system.

The present application is directed to an optical terminal including two linearly polarized optical transmit beams configured to exhibit a time-delay therebetween. The optical terminal may include a quarter-wave plate such that the linearly polarized transmit beam becomes circularly polarized. The optical terminal may also include a receiving ground terminal including a properly oriented quarter-wave plate for separating and directing the two recovered linearly polarized beams. The application is also directed to a method for reconstructing an originally transmitted data stream.