Spark plug (20) integrated fiber optic combustion pressure sensors (30, 36) are configured to decrease heat and fatigue damage to the critical diaphragm (40) and fiber tip (37). A cup-shaped diaphragm (40) having non-uniform thickness reduces stress on the diaphragm and increases the reliability of the...http://www.google.es/patents/US6131465?utm_source=gb-gplus-sharePatente US6131465 - Fiber optic combustion pressure sensors for engine knock and misfire detection
Fiber optic combustion pressure sensors for engine knock and misfire detection
