Abstract:
A semiconductor laser comprises: a substrate; a first cladding layer disposed above the substrate; a second cladding layer disposed above the first cladding layer so that the first cladding layer is positioned between the substrate and the second cladding layer; and a first mode expansion layer within the first cladding layer, a second mode expansion layer within the second cladding layer, or both the first mode expansion layer within the first cladding layer and the second mode expansion layer within the second cladding.
Abstract:
A semiconductor laser comprises: a substrate; a first cladding layer disposed above the substrate; a second cladding layer disposed above the first cladding layer so that the first cladding layer is positioned between the substrate and the second cladding layer; and a first mode expansion layer within the first cladding layer, a second mode expansion layer within the second cladding layer, or both the first mode expansion layer within the first cladding layer and the second mode expansion layer within the second cladding.
Abstract:
A laser chip comprises a first lateral portion comprising a first metal stripe, a first lateral connector coupled to the first metal stripe, a second metal stripe, and a second lateral connector coupled to the second metal stripe; a second lateral portion coupled to the first lateral portion and comprising a first bonding pad coupled to the first lateral connector, and a second bonding pad coupled to the second lateral connector. A method of DFB laser chip fabrication, the method comprises depositing a first portion of a passivation layer; depositing a second metal stripe; depositing a second portion of the passivation layer; and depositing a first metal stripe.
Abstract:
An apparatus comprises: a receiver; a transmitter; a laser device coupled to the receiver and the transmitter and comprising: a first laser configured to provide to the receiver a first optical wave centered at a first frequency, and a second laser configured to provide to the transmitter a second optical wave centered at a second frequency, the first frequency and the second frequency have a predetermined frequency spacing; and a processor coupled to the receiver, the transmitter, and the laser device, with the processor configured to control the first laser and the second laser to maintain the predetermined frequency spacing.
Abstract:
A framing method and apparatus in a passive optical network (PON) and a system, where the method includes generating a first transmission convergence (TC) frame and a second TC frame separately, wherein a sum of frame lengths of the first and the second TC frame is 125 microseconds (μs), performing bit mapping on the second TC frame to generate a third TC frame, where the bit mapping refers to identifying each bit of the second TC frame using N bits, and sending the first and the second TC frame to an optical network unit (ONU). A line rate corresponding to the second TC frame is lower than 2.488 giga bits per second (Gbps) such that a rate of a receiver on a receiving side is decreased and a bandwidth of the receiver is narrowed, thereby decreasing an optical link loss and increasing an optical power budget.
Abstract:
A signal processing method, an optical receiver and optical network system is provided. The method includes: receiving a first optical signal sent by an optical network unit, generating a second optical signal and modulating a phase of the second optical signal, obtaining at least one path of electrical signals after the first optical signal and the second optical signal separately undergo polarization splitting, frequency mixing, and optical-electrical conversion, outputting a third electrical signal after performing operation processing on the at least one path of electrical signals, and restoring a data signal according to the third electrical signal and performing sending. The embodiments example benefits are greatly reducing complexity of system implementation and maximally reducing a system upgrade cost and an optical power loss.
Abstract:
An apparatus comprises a first mirror; a second mirror; a modulation layer positioned between the first mirror and the second mirror and comprising a plurality of modulation regions; a diffraction layer positioned between the modulation layer and the second mirror, and an input port admitting a light beam into the apparatus. The light beam passes through the diffraction layer and is modulated by the modulation layer to create a first modulated beam before being reflected by the first mirror, the first mirror reflecting the first modulated beam toward the second mirror, the second mirror reflecting the first modulated beam toward the modulation layer to be modulated for at least a second time.
Abstract:
The disclosure relates to technology for signal transmission in an optical communication system. An optical transmitter comprises a directly modulated laser (DML) configured to generate a modulated optical signal in response to a modulation signal. The modulated optical signal comprises a first frequency corresponding to a logical one value in the modulation signal and a second frequency corresponding to a logical zero value in the modulation signal. The modulated optical signal has a modulation symbol rate of “R”. The transmitter comprises a controller configured to control the DML to establish a target frequency gap between the first frequency and the second frequency. The transmitter also comprises an optical band pass filter (OBPF) coupled to the DML to receive the modulated optical signal and output a filtered optical signal. The OBPF has a 3-dB bandwidth of less than R.
Abstract:
A material for blocking crosstalk, an optical assembly, and a method for preparing the material are provided. The optical assembly includes an optical receive assembly, where a periphery of the optical receive assembly includes a transparent region and a non-transparent region; the transparent region is made of the material, where a first layer of film is located on a side opposite to an optical receiving direction, and a second layer of film is located on a side opposite to the optical receive assembly; and the non-transparent region is of an electrical-signal shielding structure.
Abstract:
An apparatus comprises a first mirror; a second mirror; a modulation layer positioned between the first mirror and the second mirror and comprising a plurality of modulation regions; a diffraction layer positioned between the modulation layer and the second mirror, and an input port admitting a light beam into the apparatus. The light beam passes through the diffraction layer and is modulated by the modulation layer to create a first modulated beam before being reflected by the first mirror, the first mirror reflecting the first modulated beam toward the second mirror, the second mirror reflecting the first modulated beam toward the modulation layer to be modulated for at least a second time.