The device has a switched pumped solid laser with a light source, and a solid laser crystal enclosed in a resonator (9). A quality switch (4) increases power density, and a focusing device (7) focuses a laser beam into a combustion chamber. The source, resonator, crystal, switch, focusing device, an output mirror and a cooling device (11) that cools the resonator, are integrated into a single unit in a spark plug shaft of an engine.
QC 20111214. QC 20130807