Laser Sparkplugs

BBC reports on a new proposal to use lasers as more efficient sparkplugs. They are now tiny enough that they can fit, and the light would cause more efficient ignition all along the laser path and not just right next to the spark.

Except: three things come to mind: shock stresses, heat stresses (they claim the ceramics are more robust than normal lasers, but still), and carbon/ash buildup on the optics. Can you imagine how often you'd have to clean your plugs if your rings got scored and you started burning oil? I'm finding it harder and harder to get at the spark plugs, thanks to space-saving engine compartment designs.