| 摘要 |
PURPOSE:To eliminate a complicated optical system and improve ignitionability in an ignition device which performs ignition by a beam of light, by focusing the beam of light having plural wave length components to several places in a combustion chamber through a single light focusing device to perform ignition. CONSTITUTION:If an ignition instruction signal (a) in accordance with an engine condition is generated, an excitation lamp is turned on, and a laser oscillation signal (c) is output with a delay time t1 from a rise up of the signal (a) to oscillate laser light as shown by (d). A beam of light having plural wave length components oscillated by a laser oscillator 10 is focused in a combustion chamber by a focusing lens 7 to ignite a mixture. At this time, since a focus is in a diferent position in accordance with a wave length, the beam of light having plural wave length components is focused to plural positions f1, f2. For instance, YAG laser having the second harmonic wave unit is used for the oscillator 10. In this way, a complicated optical system is eliminated to improve ignitionability. |
