2022 年 64 巻 207 号 p. 58-64
Tiny integrated giant-pulse laser induced breakdown ignitions promise to enhance the performance of internal combustion engine. It makes possible the ignition at the optimal spatial point apart from the cylinder “cold wall” with multi-points and multi-pulses. Giant-pulse lasers can fire leaner or high-pressure mixtures that are difficult to be ignited by a conventional spark plug and thus the fuel is used efficiently, while low CO2 and harmful pollutant emissions are expected. Unfortunately, the giant-pulse laser ignition has been limited the basic researches until recently. In this paper, we'd like to review the brief history of laser ignition with regarding micro solid-state photonics. >50MW peak power and >20mJ pulse energy microchip laser is also discussed for the string ignition.