Laser safety systems, devices, and methods for use in laser projectors are described. A laser projector includes any number of laser diodes that each emit laser light, a laser diode power source, a current sensor to detect a magnitude of the electric current output by the power source, a photodetector to detect a power/intensity of the laser light, a beam splitter to direct a first portion of the light towards the photodetector and a second portion of the light towards an output on the projector, and first and second laser safety circuits responsive to signals from the photodetector and the current sensor, respectively. The laser safety circuits selectively electrically couples/uncouples the laser diodes from the power source depending on signals from the photodetector and/or the current sensor. Particular applications of the laser safety systems, devices, and methods in a wearable heads-up display are described.

Laser safety systems, devices, and methods for use in laser projectors are described. A laser projector includes any number of laser diodes that each emit laser light, a laser diode power source, a current sensor to detect a magnitude of the electric current output by the power source, a photodetector to detect a power/intensity of the laser light, a beam splitter to direct a first portion of the light towards the photodetector and a second portion of the light towards an output on the projector, and first and second laser safety circuits responsive to signals from the photodetector and the current sensor, respectively. The laser safety circuits selectively electrically couples/uncouples the laser diodes from the power source depending on signals from the photodetector and/or the current sensor. Particular applications of the laser safety systems, devices, and methods in a wearable heads-up display are described.

Laser safety systems, devices, and methods for use in laser projectors are described. A laser projector includes any number of laser diodes that each emit laser light, a laser diode power source, a current sensor to detect a magnitude of the electric current output by the power source, a photodetector to detect a power/intensity of the laser light, a beam splitter to direct a first portion of the light towards the photodetector and a second portion of the light towards an output on the projector, and first and second laser safety circuits responsive to signals from the photodetector and the current sensor, respectively. The laser safety circuits selectively electrically couples/uncouples the laser diodes from the power source depending on signals from the photodetector and/or the current sensor. Particular applications of the laser safety systems, devices, and methods in a wearable heads-up display are described.

An emitter of an optical signal includes a laser source including a control input for receiving an injection current able to modify the frequency of the optical signal, this laser source emitting the optical signal at a frequency v.sub.0 in the absence of injection current, a feedback loop able to produce an injection current that is able to decrease the linewidth of the optical signal, this feedback loop including to this end an optical filter a pass band of which contains a preset operating point corresponding to a frequency v.sub.b, and a loop for automatically controlling the frequency v.sub.b to the frequency v.sub.0, and wherein the feedback loop includes an electrical filter that is able to selectively attenuate, in the produced injection current, the amplitude of frequency components generated by the automatic-control loop.

A system includes a master oscillator configured to generate a low-power optical beam. The system also includes a planar waveguide (PWG) amplifier configured to generate a high-power optical beam using the low-power optical beam. The PWG amplifier has a larger dimension in a slow-axis direction and a smaller dimension in a fast-axis direction. The system further includes at least one adaptive optic (AO) element configured to modify the low-power optical beam along the slow-axis direction and to modify the low-power optical beam along the fast-axis direction. In addition, the system includes a feedback loop configured to control the at least one AO element. The modification in the slow-axis direction can compensate for thermal-based distortions created by the PWG amplifier, and the modification in the fast-axis direction can compensate for optical misalignment associated with the master oscillator and the PWG amplifier.

A method and apparatus for matching different impedance of optical components and a package for optical communication using a tapered transmission line (or a taper) are provided. The taper may be configured to include a first section, a second section, and a third section, each of which corresponds to different components. By way of example, the first section of the taper may be configured to be allocated to a driver to a flex joint on a printed circuit board (PCB), the second section of the taper may be configured to be allocated to a flex circuit, and the third section of the taper may be configured to be allocated to a transistor outline (TO) and submount including a directly modulated laser (DML). The taper is configured to minimize an amount of impedance mismatch between the optical components and the package.

A system for controlling an optical data transmitter includes control circuitry comprising a voltage controlled current source configured to generate a reference current configured to generate at least two output currents whose magnitudes are in a fixed ratio wherein at least one of said output currents is used by said control circuitry to control current driver circuitry, a first plurality of serially coupled resistors, a first plurality of switches, a second plurality of serially coupled resistors, a second plurality of switches, and a look-up-table configured to control the first plurality of switches and the second plurality of switches based on an input to control a ratio.

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.

An emitter of an optical signal includes a laser source including a control input for receiving an injection current able to modify the frequency of the optical signal, this laser source emitting the optical signal at a frequency v.sub.0 in the absence of injection current, a feedback loop able to produce an injection current that is able to decrease the linewidth of the optical signal, this feedback loop including to this end an optical filter a pass band of which contains a preset operating point corresponding to a frequency v.sub.b, and a loop for automatically controlling the frequency v.sub.b to the frequency v.sub.0, and wherein the feedback loop includes an electrical filter that is able to selectively attenuate, in the produced injection current, the amplitude of frequency components generated by the automatic-control loop.

A DFB laser DC-coupled output power configuration scheme with adjustable voltage difference. utilizes an external or internal power configuration unit to provide two electric DC power supplies with a fixed voltage difference for the transmitting unit TX of the DFB laser and the optical transceiver integrated chip, and at the same time optimizes the transmitting unit TX. The optimization scheme is that: the transistors in the transmitting unit TX are all low-voltage high-speed tubes, the transmitting unit TX includes a negative capacitance structure composed of capacitors C1 and C2, serving as an auxiliary structure for improving bandwidth. After optimization, the minimum voltage of the power supply voltage port TVCC of the transmitting unit TX is 2.7V and the problems that the output eye diagram is severely cracked and cannot be used when the traditional DFB laser configuration scheme with an external 3.3V power supply is tested at high temperature are solved.