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For automotive light detection and ranging (LiDAR) systems diode lasers emitting short optical pulses with a good beam quality and a low wavelength shift over a wide operating temperature range is needed. In this paper, theoretical and experimental results of broad area laser diodes specially designed for this application are presented. Optical pulse powers of tens of watts and pulse lengths in the 10 ns‐range for wavelengths near 905 nm and environmental temperatures between 15 and 85 °C are achieved. Due to the integrated Bragg grating the wavelength shift with temperature is as low as 65 pm K−1. The contact mesa with a width of 50 μm leads to a lateral M2 value of about 9. Streak camera measurements of the temporal evolution of the lateral near field intensity reveal that the highest intensity is emitted near the mesa edges. Simulation results of power current characteristics indicate that the power saturation experimentally observed can be attributed to nonlinear effects such as two‐photon‐absorption and gain compression. [ABSTRACT FROM AUTHOR]

A master oscillator power amplifier system for the generation of ns-pulses with high peak power, stabilized wavelength and narrow spectral line width will be presented. The master oscillator is a distributed feedback (DFB) ridge waveguide (RW) laser. The tapered amplifier consists of three RW sections and one flared gain-guided section. The DFB laser is operated in continuous wave mode and emits at 1064 nm with a spectral line width below 10 pm. One RW section of the amplifier acts as an optical gate for pulse selection. The tapered section amplifies the generated optical pulse. By adjusting the delay time between the current pulses injected into the picker and into the tapered section, respectively, the power of the amplified spontaneous emission was reduced below 1% of the average laser power. For an optical pulse length of 2 ns, a peak power of 16 W was obtained. A side mode suppression ratio better than 46 dB was observed. [ABSTRACT FROM AUTHOR]