The present disclosure is generally directed to a multi-channel TOSA with vertically-mounted MPDs to reduce TOSA housing dimensions and improve RF driving signal quality. In more detail, a TOSA housing consistent with the present disclosure includes at least one vertical MPD mounting surface that extends substantially transverse relative to a LD mounting surface, with the result being that a MPD coupled to the vertical MPD mounting surface gets positioned above an associated LD coupled to the LD mounting surface. The vertically-mounted MPD thus makes regions adjacent an LD that would otherwise be utilized to mount an MPD available for patterning of conductive RF traces to provide an RF driving signal to the LD. The conductive RF traces may therefore extend below the vertically-mounted MPD to a location that is proximate the LD to allow for relatively short wire bonds therebetween.

A laser power calibration method includes: receiving a first power fed back by a transmitter end; comparing a difference of the first power against a second power predefined at the transmitter end; and when the difference exceeds a predefined range, controlling an output power of the transmitter end to be a third power, wherein the third power is an average power of the first power and the second power.

The present disclosure is generally directed to a multi-channel TOSA with vertically-mounted MPDs to reduce TOSA housing dimensions and improve RF driving signal quality. In more detail, a TOSA housing consistent with the present disclosure includes at least one vertical MPD mounting surface that extends substantially transverse relative to a LD mounting surface, with the result being that a MPD coupled to the vertical MPD mounting surface gets positioned above an associated LD coupled to the LD mounting surface. The vertically-mounted MPD thus makes regions adjacent an LD that would otherwise be utilized to mount an MPD available for patterning of conductive RF traces to provide an RF driving signal to the LD. The conductive RF traces may therefore extend below the vertically-mounted MPD to a location that is proximate the LD to allow for relatively short wire bonds therebetween.

A controller includes an amplification ratio control unit, an amplification unit, a digital conversion unit, and a driving current control unit. The amplification ratio control unit is configured to generate an amplification ratio signal based on an ambient temperature of a laser diode. The amplification unit configured to amplify, based on the amplification ratio signal, a detection current from a photodiode configured to detect light output from the laser diode, and output the detection current as a voltage signal. The amplification ratio signal controls an amplification ratio of the amplification unit. The digital conversion unit is configured to convert the voltage signal into a digital signal. The driving current control unit is configured to control a driving current of a driver configured to drive the laser diode based on the digital signal.

A semiconductor laser is for generating colored light. The semiconductor laser oscillates in a longitudinal multimode. A width of a wavelength band with an intensity equal to or more than 20 dB relative to a peak intensity in a spectrum distribution of output light is equal to or less than 15 nm. A light source device may include The semiconductor laser; a wavelength estimating device configured to estimate a wavelength of light from the semiconductor laser; and an emission-light intensity setting unit configured to set an emission light intensity of the semiconductor laser in accordance with an estimation result by the wavelength estimating device.

A COB bonding laser diode interface mating device comprises a laser diode and a driver integrated circuit (2). The laser diode includes a light-emitting chip (11). The light-emitting chip (11) is a bare die directly bonded to a circuit board. The driver integrated circuit (2) is a driver chip that is a packaged chip. The light-emitting chip (11) and the driver chip are connected through a capacitor-resistor network (3). The capacitor-resistor network (3) allows the driver integrated circuit (2) to provide a bias current and a modulation current to the laser diode such that the laser diode is in an activated state. The capacitor-resistor network (3) realizes interface mating between the COB bonding laser diode and the driver integrated circuit (2), thereby solving a problem that the interface mating cannot be easily achieved, reducing costs, and improving production efficiency.

There is provided a semiconductor optical integrated device having a DFB laser, an EA modulator, and an SOA monolithically integrated, and an output light intensity of the semiconductor optical integrated device is maintained constant. The semiconductor optical integrated device includes: a DFB laser; an EA modulator connected to the DFB laser; an SOA monolithically integrated with the DFB laser and the EA modulator on a same substrate and connected to an output end of the EA modulator; and an optical receiver disposed on an output end side of the SOA and having a same composition as the SOA. The optical receiver is configured to monitor change in a detection value according to an intensity of input light to the optical receiver such that drive currents flowing in the DFB laser and the SOA are feedback controlled.

An OMA controller circuit utilizes a first ADC with an input coupled for receiving a residual error signal indicating a difference between a monitoring signal and a target data signal. A second ADC has an input coupled for receiving the target data signal. A first digital filter has an input coupled to an output of the first ADC, and a second digital filter has an input coupled to an output of the second ADC. A digital multiplier has a first input coupled to an output of the first digital filter and a second input coupled to an output of the second digital filter. An integrator has an input coupled to an output of the digital multiplier and an output providing an average error signal with sign and magnitude. The digital multiplier uses a four quadrant multiplier to perform a cross-correlation on the residual error and the target data signal.

Methods for driving a tunable laser with integrated tuning elements are disclosed. The methods can include modulating the tuning current and laser injection current such that the laser emission wavelength and output power are independently controllable. In some examples, the tuning current and laser injection current are modulated simultaneously and a wider tuning range can result. In some examples, one or both of these currents is sinusoidally modulated. In some examples, a constant output power can be achieved while tuning the emission wavelength. In some examples, the output power and tuning can follow a linear relationship. In some examples, injection current and tuning element drive waveforms necessary to achieve targeted output power and tuning waveforms can be achieved through optimization based on goodness of fit values between the targeted and actual output power and tuning waveforms.

A semiconductor laser device with external resonator with stable longitudinal mode regardless of variation of drive current is disclosed. The device includes: a semiconductor light-emitting element having a pair of end faces with a light emitting section disposed therebetween, and an external resonator configured to oscillate light emitted from the semiconductor light-emitting element, the external resonator being formed by a resonator mirror disposed outside the semiconductor light-emitting element and one of the pair of end faces that is farther from the resonator mirror, wherein, as the semiconductor light-emitting element, a semiconductor light-emitting element having a structure which does not oscillate light emitted therefrom by itself is used. The device further includes a wavelength control element disposed in the optical path within the external resonator and configured to select a wavelength range of the light, and a driver circuit configured to perform fast modulation drive of the semiconductor light-emitting element.