The present application is directed to a method of short pulse generation. The method includes the step of creating, via electrical circuitry in a master oscillator, a square wave pulse with a predetermined pulse repetition rate. The method includes the step of retiming the square pulse with a clock. The method includes the step of recovering an electrical signal from the retimed square pulse. Further, the method includes the step of sending the recovered electrical signal to a modulator for modulating an optical signal.

Provided is a technology for suppressing variations in the waveform of a light emission pulse caused by various factors in a light-emitting device. A light-emitting device is provided with: a light source 101 in which relaxation oscillation occurs immediately after energization; a light source drive circuit 104 which includes a differentiation circuit 102 having a resistor and a capacitor connected in parallel, and in which a switching element 103 for voltage application is connected in series with the differentiation circuit; a power supply circuit 105; a light-reception element 107 which detects pulsed light emitted from the light source 101; and a voltage control unit 109 which controls an output voltage from the power supply circuit 105 in correspondence with the waveform of the detected pulsed light.

A lidar system with a light source to emit a pulse of light and a receiver to detect a return pulse of light. The receiver can include a first channel to receive a first portion of the return pulse and produce a first digital output signal, and a second channel to receive a second portion of the return pulse and produce a second digital output signal. The receiver can include a logic circuit to produce an output electrical-edge signal in response to receiving the digital output signals. The receiver can also include a time-to-digital converter to determine a time interval based on an emission time of the pulse of light and based on the electrical-edge signal. The lidar system can also include a processor to determine a distance to a target based at least in part on the time interval.

A lidar system comprising with a light source, an optical link, and a sensor head. The light source can include a seed laser to produce pulses of light and an optical preamplifier to amplify the pulses of light. The optical link can convey amplified pulses of light to the sensor head remotely located from the light source. The sensor head can include an optical booster amplifier, a scanner to scan amplified output pulses of light across a field of regard, and a receiver to detect pulses of light scattered by a target located a distance from the sensor head.

A lidar system with a pulsed laser diode configured to produce an optical seed pulse of light at an operating wavelength between approximately 1400 nm and approximately 1600 nm. The lidar system may also include an optical amplifier configured to amplify the optical seed pulse to produce an eye-safe output optical pulse that is emitted into a field of view. The optical amplifier may produce an amount of amplified spontaneous emission (ASE) associated with the output optical pulse. The lidar system may include an optical filter configured to filter the output optical pulse to reduce the associated ASE. The lidar system may also include a receiver configured to detect at least a portion of the output optical pulse reflected or scattered from the field of view.

A lidar system having a light source to emit an output beam and an overlap mirror having a reflecting surface with an aperture through which the output beam passes. The lidar system may include mirrors driven by a galvanometer scanner, a resonant scanner, a microelectromechanical systems device, or a voice coil motor. The mirrors may direct the output beam toward a light source field of view (FOV) and may move the light source FOV to different locations within a field of regard. The mirrors may receive reflected portions of the output beam as an input beam and direct the input beam toward the reflecting surface of the overlap mirror. The lidar system may include a receiver to receive the input beam from the reflecting surface of the overlap mirror. The receiver may have a receiver FOV that moves synchronously with, and at least partially overlaps, the light source FOV.

A laser apparatus includes a first wavelength variable semiconductor laser that outputs first continuous-wave laser light; a first amplifier that pulses and amplifies the first laser light and outputs first pulse laser light; a wavelength conversion system that converts a wavelength of the first pulse laser light and outputs second pulse laser light; an excimer amplifier that amplifies the second pulse laser light and outputs third pulse laser light; a monitor module that measures a wavelength of the third pulse laser light; and a processor that periodically changes a target wavelength of the third pulse laser light and controls a current for changing the wavelength of the laser light from the first semiconductor laser such that the wavelength of the third pulse laser light becomes the target wavelength based on a measured value of the wavelength of the third pulse laser light output at the same target wavelength.

A lidar system with a pulsed laser diode configured to produce an optical seed pulse of light at an operating wavelength between approximately 1400 nm and approximately 1600 nm. The lidar system may also include an optical amplifier configured to amplify the optical seed pulse to produce an eye-safe output optical pulse that is emitted into a field of view. The optical amplifier may produce an amount of amplified spontaneous emission (ASE) associated with the output optical pulse. The lidar system may include an optical filter configured to filter the output optical pulse to reduce the associated ASE. The lidar system may also include a receiver configured to detect at least a portion of the output optical pulse reflected or scattered from the field of view.

A lidar system with a light source to emit a pulse of light into a field of view and a receiver to detect a return pulse of light which is reflected or scattered by a target in the field of view. The receiver may include an avalanche photodiode to generate an electrical-current pulse corresponding to the return pulse and a transimpedance amplifier to produce a voltage pulse that corresponds to the electrical-current pulse. A voltage amplifier may amplify the voltage pulse and a comparator may produce an edge signal when the amplified voltage pulse exceeds a threshold. A time-to-digital converter may determine a time interval based on an emission time of the pulse of light and based on the edge signal. A processor may determine a distance to the target using the time interval.

A lidar system with a seed laser to produce seed pulses with wavelengths between approximately 1400 nm and 2050 nm. A first amplifier amplifies the seed pulses to produce amplified seed pulses and amplified spontaneous emission (ASE). An optical filter removes at least a portion of the ASE. A second amplifier amplifies the seed pulses to produce output pulses having a repetition frequency less than or equal to 100 MHz, a duration less than or equal to 20 nanoseconds, a duty cycle less than or equal to 1%, an energy greater than or equal to 10 nanojoules, a peak power greater than or equal to 1 watt, and an average power less than or equal to 50 watts, the ASE comprising less than or equal to 25% of the average power. A sensor head directs the output pulses into a field of view and detects reflected light therefrom.