摘要:
An optical transmitter comprises a monolithic transmitter photonic integrated circuit (TxPIC) chip that includes an array of modulated sources formed on the PIC chip and having different operating wavelengths approximating a standardized wavelength grid and providing signal outputs of different wavelengths. A wavelength selective combiner is formed on the PIC chip having a wavelength grid passband response approximating the wavelength grid of the standardized wavelength grid. The signal outputs of the modulated sources optically coupled to inputs of the wavelength selective combiner to produce a combined signal output from the combiner. A first wavelength tuning element coupled to each of the modulated sources and a second wavelength tuning element coupled to the wavelength selective combiner. A wavelength monitoring unit is coupled to the wavelength selective combiner to sample the combined signal output. A wavelength control system coupled to the first and second wavelength tuning elements and to said wavelength monitoring unit to receive the sampled combined signal output. The wavelength control system adjusts the respective wavelengths of operation of the modulated sources to approximate or to be chirped to the standardized wavelength grid and for adjusting the optical combiner wavelength grid passband response to approximate the standardized wavelength grid.
摘要:
A laser source or a plurality of laser sources in a photonic integrated circuit (PIC) are provided with an electrical contact that is either segmented or is connected to a series of vernier resistor segments for supply of current to operate the laser source. In either case, at least one segment of the laser contact or at least one vernier resistor segment can be trimmed in order to vary the amount of current supplied to the laser source resulting in a change to its current density and, thus, a change in its operational wavelength while maintaining the current supplied to the laser source constant.
摘要:
A method of operating an array of integrated laser sources formed as an integrated array on a single substrate in a photonic integrated circuit (PIC) where the laser sources are designed for operation at different targeted emission wavelengths which, in toto, at least approximate a grid of spatial emission wavelengths. A first wavelength tuning element is associated with each laser source and is adjusted over time so that each laser source maintains its targeted emission wavelength. As an alternative, the drive current to each laser source may be initially set so that each laser source operates at its targeted emission wavelength. Thereafter, adjustments to retune the laser sources to their targeted emission wavelengths are accomplished by the first wavelength tuning elements. The outputs of the laser sources may be combined via an optical combiner to produce a single combined output from the PIC. A second wavelength tuning element is associated with the optical combiner so that the passband response or wavelength grid of the optical combiner may be also monitored and adjusted to better approximate the wavelength grid of the laser sources.
摘要:
A digital optical network (DON) is a new approach to low-cost, more compact optical transmitter modules and optical receiver modules for deployment in optical transport networks (OTNs). One important aspect of a digital optical network is the incorporation in these modules of transmitter photonic integrated circuit (TxPIC) chips and receiver photonic integrated circuit (TxPIC) chips in lieu of discrete modulated sources and detector sources with discrete multiplexers or demultiplexers.
摘要:
Devices and techniques for fabricating InAlGaN light-emitting devices are described that result from the removal of light-emitting layers from the sapphire growth substrate. In several embodiments, techniques for fabricating a vertical InAlGaN light-emitting diode structure that result in improved performance and or cost-effectiveness are described. Furthermore, metal bonding, substrate liftoff, and a novel RIE device separation technique are employed to efficiently produce vertical GaN LEDs on a substrate chosen for its thermal conductivity and ease of fabrication.
摘要:
Disclosed are methods for anchoring materials in or to concrete. The methods preferably comprise delivering to the concrete or masonry, the material to be anchored to the concrete or masonry or both an anchor composition comprising alkylacrylate ester monomer and a copolymer of alkylacrylate ester and methacrylic acid monomers, and free-radical catalyst.
摘要:
A FEC enhanced system for an optical transport or communication network that includes an optical transmitter that has a transmitter photonic integrated circuit (TxPIC) chip having an integrated circuit comprising an array of modulated sources providing a plurality of optical modulated channel signals comprising digital bit data streams where each signal is at a wavelength on a wavelength grid. The modulated channel signal outputs from the modulated sources are provided to an integrated multiplexer in the circuit to provide a WDM output signal at a circuit output. At least one FEC encoder is coupled to the modulated sources to encode error-correcting code containing redundant information of the data bit stream for each channel signal. An optical receiver in the network includes a receiver photonic integrated circuit (RxPIC) chip having an integrated circuit comprising an input to a demultiplexer and an array of photodetectors coupled to outputs of the demultiplexer. At least one FEC decoder is coupled to the photodetectors to provide decoded data relating to the bit error rate (BER). Information relating to the BER is provided by a controller at the optical receiver to provide real-time information to the optical transmitter relating to optical characteristics of the modulated sources based upon the BER data.
摘要:
A method for designing semiconductor light emitting devices is disclosed wherein the side surfaces (surfaces not parallel to the epitaxial layers) are formed at preferred angles relative to vertical (normal to the plane of the light-emitting active layer) to improve light extraction efficiency and increase total light output efficiency. Device designs are chosen to improve efficiency without resorting to excessive active area-yield loss due to shaping. As such, these designs are suitable for low-cost, high-volume manufacturing of semiconductor light-emitting devices with improved characteristics.
摘要:
Disclosed are compositions for anchoring materials in or to concrete or masonry. The compositions preferably comprise alkylacrylate ester monomer and a copolymer of alkylacrylate ester and methacrylic acid monomers, and free-radical catalyst.